374 results on '"Buchanan GR"'
Search Results
2. Slow disappearance of peripheral blood blasts is an adverse prognostic factor in childhood T cell acute lymphoblastic leukemia: a Pediatric Oncology Group study
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Griffin, TC, Shuster, JJ, Buchanan, GR, Murphy, SB, Camitta, BM, and Amylon, MD
- Published
- 2000
- Full Text
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3. Splenectomy in children with idiopathic thrombocytopenic purpura
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Kuhne, T, Blanchette, V, Buchanan, Gr, Ramenghi, Ugo, Donato, H, Tamminga, Ry, Rischewski, J, Berchtold, W, Imbach, P, Intercontinental Childhood ITP Study Group, and Faculteit Medische Wetenschappen/UMCG
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Male ,Pediatrics ,medicine.medical_specialty ,Adolescent ,pediatrics ,medicine.medical_treatment ,blood platelets ,Splenectomy ,thrombocytopenia ,registry ,splenectomy ,Sepsis ,Sex Factors ,Refractory ,MANAGEMENT ,Medicine ,Humans ,Prospective Studies ,Registries ,Prospective cohort study ,Child ,PLATELET ,Purpura, Thrombocytopenic, Idiopathic ,business.industry ,Platelet Count ,Remission Induction ,Age Factors ,Infant ,Hematology ,Recovery of Function ,ADULTS ,medicine.disease ,Thrombocytopenic purpura ,Clinical trial ,Vaccination ,Oncology ,Child, Preschool ,Pediatrics, Perinatology and Child Health ,IMMUNOGLOBULIN ,ITP ,Registry data ,Female ,business ,FOLLOW-UP ,INTRAVENOUS IMMUNE GLOBULIN ,Follow-Up Studies ,RESPONSES - Abstract
Background. Splenectomy is an effective procedure for children and adults with severe or refractory idiopathic thrombocytopenic purpura (ITP). Data regarding pediatric patients are limited. Procedure. Sixty-eight Intercontinental Childhood ITP Study Group (ICIS) investigators from 57 institutions in 25 countries participated in a splenectomy registry. Data from 153 patients were submitted, of whom 134 had a splenectomy and were analyzed. Results. The median age at splenectomy was 11.8 (2.7-20.7) years. The median postsplenectomy follow-up was 2.0 (0.1-4.5) years. Pre-splenectomy vaccination was not administered in 21 children (15.7%). Open and laparoscopic splenectomy procedures were performed in 67 and 65 evaluable children, respectively. Surgical technique was not reported in two children. Overall immediate platelet response to splenectomy was achieved in 113 patients (86.3%). Eighty percent of responders maintained their status of response during the following 4 years. Older age, longer duration of ITP, and male gender correlated with a complete response. Post-splenectomy sepsis was reported in seven patients without lethal outcome, although sepsis might be differently defined at participating institutions. Conclusions. Splenectomy is effective in children with ITP. Management varies greatly in different institutions. These Registry data may serve as a basis for future clinical trials to assess the indication and timing of splenectomy. Pediatr Blood Cancer 2007;49:829834. (c) 2006 Wiley-Liss, Inc.
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- 2007
4. Serotype-specific immunoglobulin G antibody responses to pneumococcal polysaccharide vaccine in children with sickle cell anemia: Effects of continued penicillin prophylaxis
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Bjornson, AB, Falletta, JM, Verter, JI, Buchanan, GR, Miller, ST, Pegelow, CH, Iyer, RV, Johnstone, HS, DeBaun, MR, Wethers, DL, Woods, GM, Holbrook, CT, Becton, DL, Kinney, TR, Reaman, GH, Kalinyak, K, Grossman, NJ, Vichinsky, E, Reid, CD, and University of Groningen
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INFECTION ,WALL POLYSACCHARIDE ,STREPTOCOCCUS-PNEUMONIAE ,STANDARDIZATION ,OPSONIC ACTIVITY ,INFLUENZAE TYPE-B ,IMMUNIZATION ,DISEASE ,RADIOIMMUNOASSAY ,SERUM - Abstract
Objectives: (1) To determine serotype-specific IgG antibody responses to reimmunization with pneumococcal polysaccharide vaccine at age 5 years ski children with sickle cell anemia and (2) to determine whether continued penicillin prophylaxis had any adverse effects on these responses. Study design: Children with sickle cell anemia, who had been treated with prophylactic penicillin for at least 2 years before their fifth birthday, were randomly selected at age 5 years to continue penicillin prophylaxis or to receive placebo treatment, These children had been immunized once or twice in early childhood with pneumococcal polysaccharide vaccine and were reimmunized at the time of randomization. Results: Serotype-specific IgG antibody responses to reimmunization varied according to pneumococcal serotype but in general were mediocre or poor; the poorest response was to serotype 6B. The antibody responses were similar in subjects with continued penicillin prophylaxis or placebo treatment, and in subjects who received one or two pneumococcal vaccinations before reimmunization. The occurrence of pneumococcal bacteremia was associated with low IgG antibody concentrations to the infecting serotype. Conclusions: Reimmunization of children with sickle cell anemia who received pneumococcal polysaccharide vaccine at age 5 years induces limited production of serotype-specific IgG antibodies, regardless of previous pneumococcal vaccine history, Continued penicillin prophylaxis does not interfere with serotype-specific IgG antibody responses to reimmunization.
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- 1996
5. Functional asplenia in hemoglobin SC disease
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Lane, PA, primary, O'Connell, JL, additional, Lear, JL, additional, Rogers, ZR, additional, Woods, GM, additional, Hassell, KL, additional, Wethers, DL, additional, Luckey, DW, additional, and Buchanan, GR, additional
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- 1995
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6. Clinical features and outcome of T-cell acute lymphoblastic leukemia in childhood with respect to alterations at the TAL1 locus: a Pediatric Oncology Group study
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Bash, RO, primary, Crist, WM, additional, Shuster, JJ, additional, Link, MP, additional, Amylon, M, additional, Pullen, J, additional, Carroll, AJ, additional, Buchanan, GR, additional, Smith, RG, additional, and Baer, R, additional
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- 1993
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7. Treatment of late bone marrow relapse in children with acute lymphoblastic leukemia: a Pediatric Oncology Group study
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Sadowitz, PD, primary, Smith, SD, additional, Shuster, J, additional, Wharam, MD, additional, Buchanan, GR, additional, and Rivera, GK, additional
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- 1993
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8. Validity, reliability, and responsiveness of a new measure of health-related quality of life in children with immune thrombocytopenic purpura: the Kids' ITP Tools.
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Klaassen RJ, Blanchette VS, Barnard D, Wakefield CD, Curtis C, Bradley CS, Neufeld EJ, Buchanan GR, Silva MP, Chan AK, and Young NL
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- 2007
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9. Childhood ITP: 12 months follow-up data from the prospective Registry I of the Intercontinental Childhood ITP Study Group (ICIS)
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Imbach P, Kühne T, Müller D, Berchtold W, Zimmerman S, Elalfy M, Buchanan GR, and ICIS (Intercontinental Childhood ITP Study Group) Registry I Participants
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- 2006
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10. The t(1;14)(p34;q11) is nonrandom and restricted to T-cell acute lymphoblastic leukemia: a Pediatric Oncology Group study
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Carroll, AJ, primary, Crist, WM, additional, Link, MP, additional, Amylon, MD, additional, Pullen, DJ, additional, Ragab, AH, additional, Buchanan, GR, additional, Wimmer, RS, additional, and Vietti, TJ, additional
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- 1990
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11. Minor elective surgical procedures using general anesthesia in children with sickle cell anemia without pre-operative blood transfusion.
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Fu T, Corrigan NJ, Quinn CT, Rogers ZR, and Buchanan GR
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- 2005
12. ITP: how much treatment is enough?
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Buchanan GR
- Abstract
Idiopathic thrombocytopenic purpura is easy to recognize and generally not serious. Yet specialists differ greatly in their approach to diagnosis and treatment. Review the rationales of the opposing camps, then make up your own mind on which makes better sense. [ABSTRACT FROM AUTHOR]
- Published
- 2000
13. Reinduction therapy in 297 children with acute lymphoblastic leukemia in first bone marrow relapse: a Pediatric Oncology Group Study
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Buchanan, GR, Rivera, GK, Boyett, JM, Chauvenet, AR, Crist, WM, and Vietti, TJ
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Many children with acute lymphoblastic leukemia (ALL) develop a marrow relapse during or shortly following initial continuation chemotherapy. Achievement of a second complete remission is the initial step in a successful retreatment effort. Reinduction results using two or three drugs have been unsatisfactory, and previous reports of four-drug reinduction programs have included relatively small numbers of patients. Pediatric Oncology Group protocol 8303 was designed for patients with ALL in first marrow relapse during or within 6 months after cessation of chemotherapy. The results of reinduction therapy in 297 study patients are described here. Four-drug reinduction therapy consisted of daily oral prednisone, weekly vincristine and daunorubicin, and asparaginase three times weekly for 4 weeks (PVDA). CNS retreatment consisted of two doses of triple intrathecal chemotherapy. Of the 297 patients receiving reinduction, 245, or 82%, entered second complete remission, six died of infection or progressive disease, and 46 others still had M2 or M3 bone marrow status. Forty of these latter patients received four doses (during a 2-week period) of teniposide and cytarabine, after which 13 (32%) achieved complete remission status. Thus, the overall second complete remission rate with PVDA with or without teniposide/cytarabine was 258 of 297, or 87%. The treatment program was generally well tolerated. Among the numerous factors analyzed by using logistic regression, only female sex (P = .035), the presence of blasts on the blood smear at the time of relapse (P = .0002), and a length of initial complete remission less than 12 months (P = .021) were independent predictors of failure to enter second remission. We conclude that the intensive reinduction program described here is a highly effective first step in the delivery of salvage therapy to patients with ALL in first marrow relapse. The current challenge is to develop improved continuation treatment for these children.
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- 1988
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14. The entire beta-globin gene cluster is deleted in a form of gamma delta beta-thalassemia
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Fearon, ER, Kazazian, HH Jr, Waber, PG, Lee, JI, Antonarakis, SE, Orkin, SH, Vanin, EF, Henthorn, PS, Grosveld, FG, Scott, AF, and Buchanan, GR
- Abstract
We have used restriction endonuclease mapping to study a deletion involving the beta-globin gene cluster in a Mexican-American family with gamma delta beta-thalassemia. Analysis of DNA polymorphisms demonstrated deletion of the beta-globin gene from the affected chromosome. Using a DNA fragment that maps greater than 40 kilobases (kb) 5' to the epsilon-gene as a probe, reduced amounts of normal fragments were found in the DNA of affected family members. Similar analysis using radiolabeled DNA fragments located 3' to the beta-globin cluster has shown that the deletion extends more than 17 kb 3' to the beta-gene, but terminates before the 3' endpoint of the Ghanian HPFH deletion. Hence, this gamma delta beta-thalassemia deletion eliminates over 105 kb of DNA and is the first report of a deletion of the entire beta-globin gene cluster.
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- 1983
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15. Terminal deoxynucleotidyl transferase-containing cells in peripheral blood: implications for the surveillance of patients with lymphoblastic leukemia or lymphoma in remission
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Froehlich, TW, Buchanan, GR, Cornet, JA, Sartain, PA, and Smith, RG
- Abstract
An indirect immunofluorescence assay was used to quantitate TdT- containing (TdT+) cells in the mononuclear leukocyte fraction of peripheral blood from normal subjects and patients with acute lymphoblastic leukemia (ALL) and lymphoblastic lymphoma (LL). In normal children (10) and adults (10), 0.036% +/- 0.014% (mean +/- SD) and 0.030% +/- 0.015% TdT+ cells were found. In peripheral bloods from 10 children receiving chemotherapy for tumors other than ALL or LL, 0.040% +/- 0.039% TdT+ cells were found. Serial determinations were performed on 15 patients with ALL or LL who were in clinical remission. Eight of these patients remained in continuous remission and always had fewer than 0.11% TdT+ cells in their peripheral blood. Three patients who developed systemic relapse were found to have progressively rising numbers of TdT+ cells in their peripheral blood prior to clinical evidence of relapse. All 3 of these patients had greater than 0.1% TdT+ cells in their peripheral blood from 3 to 8 wk prior to clinical relapse. In 3 other patients, localized extramedullary relapse developed, but no trend was found on serial TdT determinations. Thus, the indirect immunofluorescence assay for TdT detects a small population of cells in normal peripheral blood. In patients with ALL, progressive increases above this normal level were associated with subsequent bone marrow relapse.
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- 1981
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16. Bone marrow delta-aminolaevulinate synthase deficiency in a female with congenital sideroblastic anemia
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Buchanan, GR, Bottomley, SS, and Nitschke, R
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Heme biosynthesis was examined in erythroid tissue of a 4-yr-old girl with severe sideroblastic anemia since infancy, as documented by the presence of intramitochondrial deposits of iron in erythroblasts. Free red cell protoporphyrin, urinary porphyrins, and activities of erythrocyte porphobilinogen synthase, uroporphyrinogen 1 synthase, aspartate aminotransferase, and pyridoxine kinase were normal or increased. Bone marrow ferrochelatase activity was normal. Activity of bone marrow delta-aminolaevulinate (ALA) synthase was markedly reduced to 7 pmole ALA/10(6) erythroblasts/30 min (normal 127 +/- 29) but was enhanced fivefold by pyridoxal phosphate (normal 0%--25% increase). Therapy with oral pyridoxine and parenteral pyridoxal-5'-phosphate did not increase effective red cell production. The sideroblastic anemia in this patient appears to be related to a congenital defect in the initial step of heme biosynthesis.
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- 1980
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17. Platelet function in the Chediak-Higashi syndrome
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Buchanan, GR and Handin, RI
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Platelet function studies were performed on two patients with the Chediak-Higashi syndrome, one of whom had a history of easy bruising unrelated to thrombocytopenia. Both patients had prolonged bleeding times, abnormal platelet aggregation, and a defect of platelet storage granules, manifested by reduced platelet ADP, an increased ATP/ADP ratio, increased adenine nucleotide specific radioactivity after 3H- adenine labeling, and decreased platelet uptake of radioactive 5- hydroxytryptamine. These findings confirm preliminary data in animals with the Chediak-Higashi syndrome, provide and explanation for impaired primary hemostasis in these patients, and illustrate another disorder in which platelet storage-pool deficiency occurs.
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- 1976
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18. Androgen receptor and nutrient signaling pathways coordinate increased amino acid transport in prostate cancer progression
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Ng Cynthia, Bailey Charles G, Wang Qian, Tiffen Jessamy, Thoeng Annora, Minnas Vineet, Lehman Melanie L, Hendy Stephen C, Buchanan Grant, Nelson Colleen C, Rasko John EJ, and Holst Jeff
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Medicine ,Science - Published
- 2012
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19. Highlight. What is the 'cost' of acute ITP?
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Buchanan GR
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- 2007
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20. Identification of novel androgen receptor target genes in prostate cancer
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Gerald William L, Scher Howard I, Arasheben Armin, Tilley Wayne D, Cogan Jon P, Pregizer Steve, Barski Artem, Jia Li, Prescott Jennifer, Jariwala Unnati, Buchanan Grant, Coetzee Gerhard A, and Frenkel Baruch
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Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background The androgen receptor (AR) plays critical roles in both androgen-dependent and castrate-resistant prostate cancer (PCa). However, little is known about AR target genes that mediate the receptor's roles in disease progression. Results Using Chromatin Immunoprecipitation (ChIP) Display, we discovered 19 novel loci occupied by the AR in castrate resistant C4-2B PCa cells. Only four of the 19 AR-occupied regions were within 10-kb 5'-flanking regulatory sequences. Three were located up to 4-kb 3' of the nearest gene, eight were intragenic and four were in gene deserts. Whereas the AR occupied the same loci in C4-2B (castrate resistant) and LNCaP (androgen-dependent) PCa cells, differences between the two cell lines were observed in the response of nearby genes to androgens. Among the genes strongly stimulated by DHT in C4-2B cells – D-dopachrome tautomerase (DDT), Protein kinase C delta (PRKCD), Glutathione S- transferase theta 2 (GSTT2), Transient receptor potential cation channel subfamily V member 3 (TRPV3), and Pyrroline-5-carboxylate reductase 1 (PYCR1) – most were less strongly or hardly stimulated in LNCaP cells. Another AR target gene, ornithine aminotransferase (OAT), was AR-stimulated in a ligand-independent manner, since it was repressed by AR siRNA knockdown, but not stimulated by DHT. We also present evidence for in vivo AR-mediated regulation of several genes identified by ChIP Display. For example, PRKCD and PYCR1, which may contribute to PCa cell growth and survival, are expressed in PCa biopsies from primary tumors before and after ablation and in metastatic lesions in a manner consistent with AR-mediated stimulation. Conclusion AR genomic occupancy is similar between LNCaP and C4-2B cells and is not biased towards 5' gene flanking sequences. The AR transcriptionally regulates less than half the genes nearby AR-occupied regions, usually but not always, in a ligand-dependent manner. Most are stimulated and a few are repressed. In general, response is stronger in C4-2B compared to LNCaP cells. Some of the genes near AR-occupied regions appear to be regulated by the AR in vivo as evidenced by their expression levels in prostate cancer tumors of various stages. Several AR target genes discovered in the present study, for example PRKCD and PYCR1, may open avenues in PCa research and aid the development of new approaches for disease management.
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- 2007
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21. Formation of functional Tat translocases from heterologous components
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Widdick David A, Buchanan Grant, Guymer David, Hicks Matthew G, Caldelari Isabelle, Berks Ben C, and Palmer Tracy
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Microbiology ,QR1-502 - Abstract
Abstract Background The Tat pathway transports folded proteins across the cytoplasmic membrane of bacteria and the thylakoid membrane of plants. In Eschericha coli, Tat transport requires the integral membrane proteins TatA, TatB and TatC. In this study we have tested the ability of tat genes from the eubacterial species Pseudomonas syringae, Streptomyces coelicolor and Aquifex aeolicus, to compensate for the absence of the cognate E. coli tat gene, and thus to form functional Tat translocases with E. coli Tat components. Results All three subunits of the Tat system from the Gram positive organism Streptomyces coelicolor were able to form heterologous translocases with substantive Tat transport activity. However, only the TatA and TatB proteins of Pseudomonas syringae were able to functionally interact with the E. coli Tat system even though the two organisms are closely related. Of the Tat components from the phylogenetically distant hyperthermophillic bacterium Aquifex aeolicus only the TatA proteins showed any detectable level of heterologous functionality. The heterologously expressed TatA proteins of S. coelicolor and A. aeolicus were found exclusively in the membrane fraction. Conclusion Our results show that of the three Tat proteins, TatA is most likely to show cross-species complementation. By contrast, TatB and TatC do not always show cross-complementation, probably because they must recognise heterologous signal peptides. Since heterologously-expressed S. coelicolor TatA protein was functional and found only in the membrane fraction, it suggests that soluble forms of Streptomyces TatA reported by others do not play a role in protein export.
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- 2006
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22. Prophylaxis versus episodic treatment to prevent joint disease in boys with severe hemophilia.
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Manco-Johnson MJ, Abshire TC, Shapiro AD, Riske B, Hacker MR, Kilcoyne R, Ingram JD, Manco-Johnson ML, Funk S, Jacobson L, Valentino LA, Hoots WK, Buchanan GR, DiMichele D, Recht M, Brown D, Leissinger C, Bleak S, Cohen A, and Mathew P
- Abstract
Background: Effective ways to prevent arthropathy in severe hemophilia are unknown.Methods: We randomly assigned young boys with severe hemophilia A to regular infusions of recombinant factor VIII (prophylaxis) or to an enhanced episodic infusion schedule of at least three doses totaling a minimum of 80 IU of factor VIII per kilogram of body weight at the time of a joint hemorrhage. The primary outcome was the incidence of bone or cartilage damage as detected in index joints (ankles, knees, and elbows) by radiography or magnetic resonance imaging (MRI).Results: Sixty-five boys younger than 30 months of age were randomly assigned to prophylaxis (32 boys) or enhanced episodic therapy (33 boys). When the boys reached 6 years of age, 93% of those in the prophylaxis group and 55% of those in the episodic-therapy group were considered to have normal index-joint structure on MRI (P=0.006). The relative risk of MRI-detected joint damage with episodic therapy as compared with prophylaxis was 6.1 (95% confidence interval, 1.5 to 24.4). The mean annual numbers of joint and total hemorrhages were higher at study exit in the episodic-therapy group than in the prophylaxis group (P<0.001 for both comparisons). High titers of inhibitors of factor VIII developed in two boys who received prophylaxis; three boys in the episodic-therapy group had a life-threatening hemorrhage. Hospitalizations and infections associated with central-catheter placement did not differ significantly between the two groups.Conclusions: Prophylaxis with recombinant factor VIII can prevent joint damage and decrease the frequency of joint and other hemorrhages in young boys with severe hemophilia A. (ClinicalTrials.gov number, NCT00207597 [ClinicalTrials.gov].). [ABSTRACT FROM AUTHOR]- Published
- 2007
23. Newly diagnosed idiopathic thrombocytopenic purpura in childhood: an observational study.
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Kühne T, Imbach P, Bolton-Maggs PHB, Berchtold W, Blanchette V, Buchanan GR, and Intercontinental Childhood ITP Study Group
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- 2001
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24. Barriers to and Facilitators of Iron Therapy in Children with Iron Deficiency Anemia.
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Powers JM, Nagel M, Raphael JL, Mahoney DH, Buchanan GR, and Thompson DI
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- Administration, Oral, Adult, Child, Preschool, Female, Health Services Accessibility, Humans, Infant, Male, Parents, Prospective Studies, Anemia, Iron-Deficiency drug therapy, Iron administration & dosage
- Abstract
Objective: To characterize barriers to and facilitators of successful iron therapy in young children with iron deficiency anemia (IDA) from an in-depth parental perspective., Study Design: Prospective, mixed methods study of children age 9 months to 4 years with a diagnosis of nutritional IDA by clinical history and laboratory criteria and their parents. Clinical data were obtained from the electronic health record. Semistructured interviews focused on knowledge of IDA, clinical effects, experience with iron therapies, and motivation were conducted with the parent who identified as the child's primary caregiver., Results: Twenty patient-parent dyads completed the study; 80% (n = 16) identified as Hispanic/Latino (white). Patients' median age was 23 months (50% male); median initial hemoglobin concentration was 8.2 g/dL and duration of oral iron therapy was 3 months. Parents' median age was 29 years (85% female); 8 interviews (40%) were conducted in Spanish. Barriers included difficulty in administering oral iron owing to side effects and poor taste. Facilitators included provision of specific instructions; support from healthcare providers and additional caregivers at home; motivation to benefit child's health, which was strengthened by strong emotional reactions (ie, stress, anxiety) to therapy and follow-up; and an appreciation of child's improvement with successful completion of therapy., Conclusions: Our findings support the need for interventions designed to promote oral iron adherence in children with IDA. Rather than focusing on knowledge content related to IDA, interventions should aim to increase parental motivation by emphasizing the health benefits of adhering to iron therapy and avoiding more invasive interventions., (Copyright © 2019 Elsevier Inc. All rights reserved.)
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- 2020
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25. Factor VIII prophylaxis effects outweigh other hemostasis contributors in predicting severe haemophilia A joint outcomes.
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Warren BB, Jacobson L, Kempton C, Buchanan GR, Recht M, Brown D, Leissinger C, Shapiro AD, Abshire TC, and Manco-Johnson MJ
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- Factor VIII pharmacology, Female, Hemophilia A pathology, Hemostasis, Humans, Male, Factor VIII therapeutic use, Hemophilia A complications, Hemophilia A drug therapy, Joint Diseases etiology
- Abstract
Introduction: The Joint Outcome Study (JOS) demonstrated that previously untreated children with severe haemophilia A treated with prophylactic factor VIII (FVIII) concentrate had superior joint outcomes at age 6 years compared to those children treated episodically for bleeding. However, variation in joint outcome within each treatment arm was not well explained., Aim: In this study, we sought to better understand variation in joint outcomes at age 6 years in participants of the JOS., Methods: We evaluated the influence of FVIII half-life, treatment adherence, constitutional coagulant and anticoagulant proteins, and global assays on joint outcomes (number of joint bleeds, total number of bleeds, total MRI score and joint physical exam score). Logistic regression was used to evaluate the association of variables with joint failure status on MRI, defined as presence of subchondral cyst, surface erosion or joint-space narrowing. Each parameter was also correlated with each joint outcome using Spearman correlations., Results: Prophylaxis treatment arm and FVIII trough were each found to reduce risk of joint failure on univariate logistic regression analysis. When controlling for treatment arm, FVIII trough was no longer significant, likely because of the high level of covariation between these variables. We found no consistent correlation between any laboratory assay performed and any joint outcome parameter measured., Conclusion: In the JOS, the effect of prescribed prophylactic FVIII infusions on joint outcome overshadowed the contribution of treatment adherence, FVIII half-life, global assays of coagulation and constitutional coagulation proteins. (ClinicalTrials.gov number, NCT00207597)., (© 2019 John Wiley & Sons Ltd.)
- Published
- 2019
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26. Second-line treatments in children with immune thrombocytopenia: Effect on platelet count and patient-centered outcomes.
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Grace RF, Shimano KA, Bhat R, Neunert C, Bussel JB, Klaassen RJ, Lambert MP, Rothman JA, Breakey VR, Hege K, Bennett CM, Rose MJ, Haley KM, Buchanan GR, Geddis A, Lorenzana A, Jeng M, Pastore YD, Crary SE, Neier M, Neufeld EJ, Neu N, Forbes PW, and Despotovic JM
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- Adolescent, Child, Child, Preschool, Disease-Free Survival, Female, Humans, Infant, Male, Platelet Count, Prospective Studies, Survival Rate, Time Factors, Purpura, Thrombocytopenic, Idiopathic blood, Purpura, Thrombocytopenic, Idiopathic drug therapy, Quality of Life, Receptors, Fc administration & dosage, Recombinant Fusion Proteins administration & dosage, Rituximab administration & dosage, Thrombopoietin administration & dosage
- Abstract
Immune thrombocytopenia (ITP) is an autoimmune bleeding disorder with isolated thrombocytopenia and hemorrhagic risk. While many children with ITP can be safely observed, treatments are often needed for various reasons, including to decrease bleeding, or to improve health related quality of life (HRQoL). There are a number of available second-line treatments, including rituximab, thrombopoietin-receptor agonists, oral immunosuppressive agents, and splenectomy, but data comparing treatment outcomes are lacking. ICON1 is a prospective, multi-center, observational study of 120 children starting second-line treatments for ITP designed to compare treatment outcomes including platelet count, bleeding, and HRQoL utilizing the Kids ITP Tool (KIT). While all treatments resulted in increased platelet counts, romiplostim had the most pronounced effect at 6 months (P = .04). Only patients on romiplostim and rituximab had a significant reduction in both skin-related (84% to 48%, P = .01 and 81% to 43%, P = .004) and non-skin-related bleeding symptoms (58% to 14%, P = .0001 and 54% to 17%, P = .0006) after 1 month of treatment. HRQoL significantly improved on all treatments. However, only patients treated with eltrombopag had a median improvement in KIT scores at 1 month that met the minimal important difference (MID). Bleeding, platelet count, and HRQoL improved in each treatment group, but the extent and timing of the effect varied among treatments. These results are hypothesis generating and help to improve our understanding of the effect of each treatment on specific patient outcomes. Combined with future randomized trials, these findings will help clinicians select the optimal second-line treatment for an individual child with ITP., (© 2019 Wiley Periodicals, Inc.)
- Published
- 2019
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27. Disorders of Iron Metabolism: New Diagnostic and Treatment Approaches to Iron Deficiency.
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Powers JM and Buchanan GR
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- Adolescent, Anemia diagnosis, Anemia therapy, Anemia, Iron-Deficiency diagnosis, Anemia, Iron-Deficiency therapy, Child, Preschool, Female, Humans, Infant, Iron administration & dosage, Iron therapeutic use, Male, Anemia metabolism, Anemia, Iron-Deficiency metabolism, Hepcidins metabolism, Iron metabolism
- Abstract
Iron deficiency anemia is the leading cause of anemia worldwide and affects many young children and adolescent girls in the United States. Its signs and symptoms are subtle despite significant clinical effects. Iron deficiency anemia is diagnosed clinically by the presence of risk factors and microcytic anemia. Improvement following a trial of oral iron therapy is confirmative. An array of iron laboratory tests is available with variable indications. Clinical trial and iron absorption data support a shift to lower-dose oral iron therapy. Intravenous iron should be considered in children who fail oral iron or who have more complex disorders., (Copyright © 2019 Elsevier Inc. All rights reserved.)
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- 2019
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28. Physician decision making in selection of second-line treatments in immune thrombocytopenia in children.
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Grace RF, Despotovic JM, Bennett CM, Bussel JB, Neier M, Neunert C, Crary SE, Pastore YD, Klaassen RJ, Rothman JA, Hege K, Breakey VR, Rose MJ, Shimano KA, Buchanan GR, Geddis A, Haley KM, Lorenzana A, Thompson A, Jeng M, Neufeld EJ, Brown T, Forbes PW, and Lambert MP
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- Child, Decision Making, Female, Humans, Immunosuppressive Agents therapeutic use, Male, Physicians psychology, Rituximab therapeutic use, Splenectomy, Clinical Decision-Making, Purpura, Thrombocytopenic, Idiopathic drug therapy
- Abstract
Immune thrombocytopenia (ITP) is an acquired autoimmune bleeding disorder which presents with isolated thrombocytopenia and risk of hemorrhage. While most children with ITP promptly recover with or without drug therapy, ITP is persistent or chronic in others. When needed, how to select second-line therapies is not clear. ICON1, conducted within the Pediatric ITP Consortium of North America (ICON), is a prospective, observational, longitudinal cohort study of 120 children from 21 centers starting second-line treatments for ITP which examined treatment decisions. Treating physicians reported reasons for selecting therapies, ranking the top three. In a propensity weighted model, the most important factors were patient/parental preference (53%) and treatment-related factors: side effect profile (58%), long-term toxicity (54%), ease of administration (46%), possibility of remission (45%), and perceived efficacy (30%). Physician, health system, and clinical factors rarely influenced decision-making. Patient/parent preferences were selected as reasons more often in chronic ITP (85.7%) than in newly diagnosed (0%) or persistent ITP (14.3%, P = .003). Splenectomy and rituximab were chosen for the possibility of inducing long-term remission (P < .001). Oral agents, such as eltrombopag and immunosuppressants, were chosen for ease of administration and expected adherence (P < .001). Physicians chose rituximab in patients with lower expected adherence (P = .017). Treatment choice showed some physician and treatment center bias. This study illustrates the complexity and many factors involved in decision-making in selecting second-line ITP treatments, given the absence of comparative trials. It highlights shared decision-making and the need for well-conducted, comparative effectiveness studies to allow for informed discussion between patients and clinicians., (© 2018 Wiley Periodicals, Inc.)
- Published
- 2018
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29. Effect of Different Iron Preparations for Young Children With Iron-Deficiency Anemia-Reply.
- Author
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Powers JM, Buchanan GR, and McCavit TL
- Subjects
- Child, Hemoglobins, Humans, Infant, Anemia, Iron-Deficiency, Iron Deficiencies
- Published
- 2017
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30. Potential for Improved Screening, Diagnosis, and Treatment for Iron Deficiency and Iron Deficiency Anemia in Young Children.
- Author
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Powers JM and Buchanan GR
- Subjects
- Child, Child, Preschool, Ferritins, Humans, Infant, Iron, Anemia, Iron-Deficiency, Mass Screening
- Published
- 2017
- Full Text
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31. Patterns and influences in health-related quality of life in children with immune thrombocytopenia: A study from the Dallas ITP Cohort.
- Author
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Flores A, Klaassen RJ, Buchanan GR, and Neunert CE
- Subjects
- Adolescent, Child, Child, Preschool, Cohort Studies, Female, Humans, Male, Prospective Studies, Purpura, Thrombocytopenic, Idiopathic therapy, Surveys and Questionnaires, Texas, Purpura, Thrombocytopenic, Idiopathic complications, Quality of Life
- Abstract
Background: Relationships between clinical/demographic factors and health-related quality of life (HRQoL) in childhood immune thrombocytopenia (ITP) remain poorly understood. Recent studies reveal conflicting information about factors that contribute to HRQoL., Methods: This was a prospective, single-institution, cohort study of newly diagnosed children with ITP. Serial evaluations of HRQoL were performed using the Kid's ITP Tools (KIT), scored from 0 (worst) to 100 (best), at enrollment and 1 week, 6 months, and 12 months following diagnosis. All visits included bleeding severity grading. Relationships between HRQoL and platelet count, treatment, bleeding severity, and course of disease were examined., Results: A total of 99 children with newly diagnosed ITP were evaluable for analysis. KIT scores were low at diagnosis for parents (median 26, range 15-43) and children (median 65, range 55-81) and were not influenced by age or platelet count. At diagnosis, children who received treatment had lower platelet counts (P = 0.005), more severe hemorrhage (P < 0.0125), and lower HRQoL by parent, child, and proxy reporting (P < 0.05). Oral bleeding negatively impacted proxy-reported disease burden at diagnosis (P = 0.01). Persistence of disease and lower platelet counts at 6 and 12 month visits were the only factors noted to consistently impact quality of life beyond diagnosis for both parents and children., Conclusions: HRQoL is low at diagnosis but significantly improves over time. Patients with ongoing disease and lower platelet counts continue to have significant disease burden., (© 2017 Wiley Periodicals, Inc.)
- Published
- 2017
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32. Effect of Low-Dose Ferrous Sulfate vs Iron Polysaccharide Complex on Hemoglobin Concentration in Young Children With Nutritional Iron-Deficiency Anemia: A Randomized Clinical Trial.
- Author
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Powers JM, Buchanan GR, Adix L, Zhang S, Gao A, and McCavit TL
- Subjects
- Anemia, Iron-Deficiency etiology, Child, Preschool, Double-Blind Method, Female, Ferritins blood, Ferrous Compounds administration & dosage, Ferrous Compounds adverse effects, Hemoglobin A metabolism, Humans, Infant, Iron metabolism, Iron Compounds administration & dosage, Iron Compounds adverse effects, Lost to Follow-Up, Male, Medication Adherence statistics & numerical data, Polysaccharides administration & dosage, Polysaccharides adverse effects, Treatment Outcome, Anemia, Iron-Deficiency blood, Anemia, Iron-Deficiency drug therapy, Child Nutrition Disorders complications, Ferrous Compounds pharmacology, Hemoglobin A drug effects, Iron Compounds pharmacology, Polysaccharides pharmacology
- Abstract
Importance: Iron-deficiency anemia (IDA) affects millions of persons worldwide, and is associated with impaired neurodevelopment in infants and children. Ferrous sulfate is the most commonly prescribed oral iron despite iron polysaccharide complex possibly being better tolerated., Objective: To compare the effect of ferrous sulfate with iron polysaccharide complex on hemoglobin concentration in infants and children with nutritional IDA., Design, Setting, and Participants: Double-blind, superiority randomized clinical trial of infants and children aged 9 to 48 months with nutritional IDA (assessed by history and laboratory criteria) that was conducted in an outpatient hematology clinic at a US tertiary care hospital from September 2013 through November 2015; 12-week follow-up ended in January 2016., Interventions: Three mg/kg of elemental iron once daily as either ferrous sulfate drops or iron polysaccharide complex drops for 12 weeks., Main Outcomes and Measures: Primary outcome was change in hemoglobin over 12 weeks. Secondary outcomes included complete resolution of IDA (defined as hemoglobin concentration >11 g/dL, mean corpuscular volume >70 fL, reticulocyte hemoglobin equivalent >25 pg, serum ferritin level >15 ng/mL, and total iron-binding capacity <425 μg/dL at the 12-week visit), changes in serum ferritin level and total iron-binding capacity, adverse effects., Results: Of 80 randomized infants and children (median age, 22 months; 55% male; 61% Hispanic white; 40 per group), 59 completed the trial (28 [70%] in ferrous sulfate group; 31 [78%] in iron polysaccharide complex group). From baseline to 12 weeks, mean hemoglobin increased from 7.9 to 11.9 g/dL (ferrous sulfate group) vs 7.7 to 11.1 g/dL (iron complex group), a greater difference of 1.0 g/dL (95% CI, 0.4 to 1.6 g/dL; P < .001) with ferrous sulfate (based on a linear mixed model). Proportion with a complete resolution of IDA was higher in the ferrous sulfate group (29% vs 6%; P = .04). Median serum ferritin level increased from 3.0 to 15.6 ng/mL (ferrous sulfate) vs 2.0 to 7.5 ng/mL (iron complex) over 12 weeks, a greater difference of 10.2 ng/mL (95% CI, 6.2 to 14.1 ng/mL; P < .001) with ferrous sulfate. Mean total iron-binding capacity decreased from 501 to 389 μg/dL (ferrous sulfate) vs 506 to 417 μg/dL (iron complex) (a greater difference of -50 μg/dL [95% CI, -86 to -14 μg/dL] with ferrous sulfate; P < .001). There were more reports of diarrhea in the iron complex group than in the ferrous sulfate group (58% vs 35%, respectively; P = .04)., Conclusions and Relevance: Among infants and children aged 9 to 48 months with nutritional iron-deficiency anemia, ferrous sulfate compared with iron polysaccharide complex resulted in a greater increase in hemoglobin concentration at 12 weeks. Once daily, low-dose ferrous sulfate should be considered for children with nutritional iron-deficiency anemia., Trial Registration: clinicaltrials.gov Identifier: NCT01904864.
- Published
- 2017
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33. Iron Deficiency Anemia in Adolescents Who Present with Heavy Menstrual Bleeding.
- Author
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Cooke AG, McCavit TL, Buchanan GR, and Powers JM
- Subjects
- Adolescent, Anemia, Iron-Deficiency blood, Anemia, Iron-Deficiency etiology, Blood Transfusion methods, Blood Transfusion statistics & numerical data, Child, Contraceptives, Oral, Combined therapeutic use, Emergency Service, Hospital statistics & numerical data, Female, Ferrous Compounds administration & dosage, Hemoglobins analysis, Hospitalization, Humans, Iron blood, Male, Menorrhagia blood, Menorrhagia complications, Retrospective Studies, Texas, Anemia, Iron-Deficiency therapy, Menorrhagia therapy
- Abstract
Study Objective: To assess the clinical severity and initial treatment of iron deficiency anemia (IDA) in female adolescents with heavy menstrual bleeding (HMB) in our center., Design: Retrospective cohort study of electronic medical records via search of administrative records using International Classification of Diseases Ninth Revision codes for IDA or unspecified anemia and disorders of menstruation., Setting: Children's Medical Center in Dallas, Texas., Participants: One hundred seven patients with HMB and concomitant IDA (median age, 14.4 years) who presented to the outpatient, emergency department, and/or inpatient settings., Results: The median initial hemoglobin concentration for all patients (n = 107) was 7.4 g/dL, and most (74%, n = 79) presented to the emergency department or via inpatient transfer. Symptomatic IDA was treated with blood transfusion in 46 (43%, n = 46). Ferrous sulfate was the most commonly prescribed oral iron therapy. Seven patients received intravenous iron therapy either initially or after oral iron treatment failure. Combined oral contraceptives were commonly prescribed for abnormal uterine bleeding, yet 10% of patients (n = 11) received no hormonal therapy during their initial management. Evaluation for underlying bleeding disorders was inconsistent., Conclusion: Severe anemia because of IDA and HMB resulting in urgent medical care, including hospitalization and blood transfusion, is a common but underemphasized problem in adolescent girls. In addition to prevention and early diagnosis, meaningful efforts to improve initial management of adolescents with severe HMB and IDA are necessary., (Copyright © 2016 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.)
- Published
- 2017
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34. Intravenous Ferric Carboxymaltose in Children with Iron Deficiency Anemia Who Respond Poorly to Oral Iron.
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Powers JM, Shamoun M, McCavit TL, Adix L, and Buchanan GR
- Subjects
- Administration, Oral, Adolescent, Child, Child, Preschool, Cohort Studies, Female, Humans, Infant, Infusions, Intravenous, Iron administration & dosage, Male, Maltose administration & dosage, Retrospective Studies, Treatment Outcome, Anemia, Iron-Deficiency drug therapy, Ferric Compounds administration & dosage, Maltose analogs & derivatives
- Abstract
Objective: To assess the benefits and risks of intravenous (IV) ferric carboxymaltose (FCM) in children with iron deficiency anemia (IDA)., Study Design: In a retrospective cohort study of patients seen at our center, we identified all FCM infusions in children with IDA over a 12-month period through a query of pharmacy records. Clinical data, including hematologic response and adverse effects, were extracted from the electronic medical record., Results: A total of 116 IV FCM infusions were administered to 72 patients with IDA refractory to oral iron treatment (median age, 13.7 years; range, 9 months to 18 years). Median preinfusion and postinfusion hemoglobin values were 9.1 g/dL and 12.3 g/dL, respectively (at 4-12 weeks after the initial infusion; n = 53). Sixty-five patients (84%) experienced no adverse effects. Minor transient complications were encountered during or immediately after 7 infusions., Conclusion: FCM administered as a short IV infusion without a test dose proved to be safe and highly effective in a small yet diverse population of infants, children, and adolescents with IDA refractory to oral iron therapy., (Copyright © 2016 Elsevier Inc. All rights reserved.)
- Published
- 2017
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35. Deficiencies in the Management of Iron Deficiency Anemia During Childhood.
- Author
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Powers JM, Daniel CL, McCavit TL, and Buchanan GR
- Subjects
- Adolescent, Anemia, Iron-Deficiency etiology, Child, Child, Preschool, Female, Humans, Male, Retrospective Studies, Anemia, Iron-Deficiency diagnosis, Anemia, Iron-Deficiency drug therapy, Iron administration & dosage
- Abstract
Limited high-quality evidence supports the management of iron deficiency anemia (IDA). To assess our institutional performance in this area, we retrospectively reviewed IDA treatment practices in 195 consecutive children referred to our center from 2006 to mid-2010. The majority of children were ≤4 years old (64%) and had nutritional IDA (74%). In 11- to 18-year-old patients (31%), the primary etiology was menorrhagia (42%). Many were referred directly to the emergency department and/or prescribed iron doses outside the recommended range. Poor medication adherence and being lost-to-follow-up were common. Substantial improvements are required in the management of IDA., (© 2016 Wiley Periodicals, Inc.)
- Published
- 2016
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36. Occult hemorrhage in children with severe ITP.
- Author
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Flores A and Buchanan GR
- Subjects
- Adolescent, Child, Child, Preschool, Female, Hemorrhage blood, Hemorrhage epidemiology, Hemorrhage etiology, Humans, Infant, Intracranial Hemorrhages epidemiology, Intracranial Hemorrhages etiology, Magnetic Resonance Imaging, Male, Platelet Count, Prospective Studies, Purpura, Thrombocytopenic, Idiopathic complications, Purpura, Thrombocytopenic, Idiopathic epidemiology, Intracranial Hemorrhages blood, Purpura, Thrombocytopenic, Idiopathic blood
- Abstract
Little is known about the frequency and significance of clinically unapparent or occult hemorrhage in ITP. Therefore, we prospectively explored the sites and frequency of occult bleeding in children with severe ITP at diagnosis or upon symptomatic relapse in a prospective, single-institution cohort study of patients ≤ 18 years of age and a platelet count ≤ 10,000/mm(3) . Data collected included bleeding severity assessment, urinalysis, fecal occult blood testing, and non-contrast brain MRI. Stool and urine samples were tested within 7 days of diagnosis or symptomatic relapse. Three months after diagnosis or relapse a noncontrast brain MRI evaluated hemosiderin deposits resulting from prior localized hemorrhage. Fifty-two ITP patients were enrolled with a mean platelet count of 4,000/mm(3) . A significant occurrence of occult hemorrhage was identified in the urine (27%) compared with clinically overt hematuria (0.91%, P < 0.0005). CNS microbleeding in the superficial cortex of the left frontal lobe was identified in one child with occult bleeding in the urinary tract. There was no relationship between occult hemorrhage and bleeding manifestations on physical examination. Occult hemorrhage was not a harbinger of subsequent bleeding. Our findings suggest that occult hemorrhage occurs with greater frequency than overt bleeding in children with severe ITP. CNS microbleeding is a potential risk in this patient population. Assessment of brain microbleeds and microscopic hematuria in this patient population require additional study., (© 2015 Wiley Periodicals, Inc.)
- Published
- 2016
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37. Sports Participation in Children and Adolescents with Immune Thrombocytopenia (ITP).
- Author
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Kumar M, Lambert MP, Breakey V, Buchanan GR, Neier M, Neufeld EJ, Kempert P, Neunert CE, Nottage K, and Klaassen RJ
- Subjects
- Adolescent, Child, Child, Preschool, Female, Humans, Male, Platelet Count, Purpura, Thrombocytopenic, Idiopathic therapy, Athletic Performance, Purpura, Thrombocytopenic, Idiopathic blood, Quality of Life
- Abstract
We surveyed 278 pediatric hematologists/oncologists regarding how children with immune thrombocytopenia (ITP) are counseled for participation in sports. Results show substantial variation in physician perception of contact risk for different sports, and the advice offered about restriction of sport activities of affected children. Many physicians recommend restriction of sports when platelet counts are under 50 × 10(9) /L. Such restriction may affect the child's quality of life despite their having an overall benign disease., (© 2015 Wiley Periodicals, Inc.)
- Published
- 2015
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38. Management of iron deficiency anemia: a survey of pediatric hematology/oncology specialists.
- Author
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Powers JM, McCavit TL, and Buchanan GR
- Subjects
- Adolescent, Anemia, Iron-Deficiency blood, Cross-Sectional Studies, Disease Management, Female, Ferritins blood, Follow-Up Studies, Humans, Infant, Iron Deficiencies, Male, Prognosis, Specialization, Surveys and Questionnaires, Anemia, Iron-Deficiency prevention & control, Hematology, Iron administration & dosage, Medical Oncology
- Abstract
Background: Iron deficiency anemia (IDA) is the most common hematologic condition in children and adolescents in the United States (US). No prior reports have described the management of IDA by a large cohort of pediatric hematology/oncology specialists., Procedure: A 20-question electronic survey that solicited responses to two hypothetical cases of IDA was sent to active members of the American Society of Pediatric Hematology/Oncology (ASPHO) in the US., Results: Of 1,217 recipients, 398 (32.7%) reported regularly treating IDA and completed the survey. In a toddler with nutritional IDA, 15% (N = 61) of respondents reported ordering no diagnostic test beyond a complete blood count. Otherwise, wide variability in laboratory testing was reported. For treatment, most respondents would prescribe ferrous sulfate (N = 335, 84%) dosed at 6 mg/kg/day (N = 248, 62%) divided twice daily (N = 272, 68%). The recommended duration of iron treatment after resolution of anemia and normalized serum ferritin varied widely from 0 to 3 months. For an adolescent with heavy menstrual bleeding and IDA, most respondents recommended ferrous sulfate (N = 327, 83%), with dosing based on the number of tablets daily. For IDA refractory to oral treatment, intravenous iron therapy was recommended most frequently, 48% (N = 188) using iron sucrose, 17% (N = 68) ferric gluconate, and 15% (N = 60) low molecular weight iron dextran., Conclusion: The approach to diagnosis and treatment of IDA in childhood was widely variable among responding ASPHO members. Given the lack of an evidence base to guide clinical decision making, further research investigating IDA management is needed., (© 2015 Wiley Periodicals, Inc.)
- Published
- 2015
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39. Evidence gaps in the management of sickle cell disease: A summary of needed research.
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Savage WJ, Buchanan GR, Yawn BP, Afenyi-Annan AN, Ballas SK, Goldsmith JC, Hassell KL, James AH, John-Sowah J, Jordan L, Lottenberg R, Murad MH, Ortiz E, Tanabe PJ, Ware RE, and Lanzkron SM
- Subjects
- Anemia, Sickle Cell complications, Erythrocyte Transfusion, Evidence-Based Medicine, Humans, Hydroxyurea administration & dosage, Hydroxyurea adverse effects, Hydroxyurea therapeutic use, Anemia, Sickle Cell therapy, Practice Guidelines as Topic
- Published
- 2015
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40. Severe bleeding events in adults and children with primary immune thrombocytopenia: a systematic review.
- Author
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Neunert C, Noroozi N, Norman G, Buchanan GR, Goy J, Nazi I, Kelton JG, and Arnold DM
- Subjects
- Adult, Age Factors, Cerebral Hemorrhage blood, Cerebral Hemorrhage etiology, Child, Hemorrhage blood, Hemorrhage therapy, Humans, Platelet Count, Predictive Value of Tests, Prognosis, Purpura, Thrombocytopenic, Idiopathic blood, Purpura, Thrombocytopenic, Idiopathic diagnosis, Purpura, Thrombocytopenic, Idiopathic therapy, Risk Assessment, Risk Factors, Severity of Illness Index, Hemorrhage etiology, Purpura, Thrombocytopenic, Idiopathic complications
- Abstract
Background: The burden of severe bleeding in adults and children with immune thrombocytopenia (ITP) has not been established., Objectives: To describe the frequency and severity of bleeding events in patients with ITP, and the methods used to measure bleeding in ITP studies., Patients/methods: We performed a systematic review of all prospective ITP studies that enrolled 20 or more patients. Two reviewers searched Medline, Embase, CINAHL and the Cochrane registry up to May 2014. Overall weighted proportions were estimated using a random effects model. Measurement properties of bleeding assessment tools were evaluated., Results: We identified 118 studies that reported bleeding (n = 10 908 patients). Weighted proportions for intracerebral hemorrhage (ICH) were 1.4% for adults (95% confidence interval [CI], 0.9-2.1%) and 0.4% for children (95% CI, 0.2-0.7%; P < 0.01), most of whom had chronic ITP. The weighted proportion for severe (non-ICH) bleeding was 9.6% for adults (95% CI, 4.1-17.1%) and 20.2% for children (95% CI, 10.0-32.9%; P < 0.01) with newly-diagnosed or chronic ITP. Methods of reporting and definitions of severe bleeding were highly variable in primary studies. Two bleeding assessment tools (Buchanan 2002 for children; Page 2007 for adults) demonstrated adequate inter-rater reliability and validity in independent assessments., Conclusions: ICH was more common in adults and tended to occur during chronic ITP; other severe bleeds were more common in children and occurred at all stages of disease. Reporting of non-ICH bleeding was variable across studies. Further attention to ITP-specific bleeding measurement in clinical trials is needed to improve standardization of this important outcome for patients., Competing Interests: of Conflict of Interests D. M. Arnold reports grants from Amgen and Glaxo-SmithKline and honoraria from Amgen and Bristol Meyers Squibb outside of the submitted work. The other authors state that they have no conflict of interests., (© 2014 International Society on Thrombosis and Haemostasis.)
- Published
- 2015
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41. Long-term use of the thrombopoietin-mimetic romiplostim in children with severe chronic immune thrombocytopenia (ITP).
- Author
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Bussel JB, Hsieh L, Buchanan GR, Stine K, Kalpatthi R, Gnarra DJ, Ho RH, Nie K, and Eisen M
- Subjects
- Adolescent, Child, Child, Preschool, Chronic Disease, Female, Humans, Infant, Longitudinal Studies, Male, Platelet Count, Recombinant Fusion Proteins adverse effects, Thrombopoietin adverse effects, Treatment Outcome, Blood Platelets drug effects, Purpura, Thrombocytopenic, Idiopathic drug therapy, Receptors, Fc therapeutic use, Receptors, Thrombopoietin agonists, Recombinant Fusion Proteins therapeutic use, Thrombopoietin therapeutic use
- Abstract
Background: Treatment of chronic severe pediatric ITP is not well studied. In a phase 1/2 12-16-week study, 15/17 romiplostim-treated patients achieved platelet counts ≥50 × 10
9 /L, and romiplostim treatment was well tolerated. In a subsequent open-label extension (≤109 weeks), 20/22 patients received romiplostim; all achieved platelet counts >50 × 109 /L. Twelve patients continued in a second extension (≤127 weeks). Longitudinal data from start of romiplostim treatment through the two extensions were evaluated to investigate the safety and efficacy of long-term romiplostim treatment in chronic severe pediatric ITP., Procedure: Patients received weekly subcutaneous romiplostim, adjusted by 1 µg/kg/week to maintain platelet counts (50-200 × 109 /L, maximum dose 10 µg/kg). Bone marrow examinations were not required., Results: At baseline, patients were median age 10.0 years; median ITP duration 2.4 years; median platelet count 13 × 109 /L; 73% were male; and 36% had prior splenectomy. Median romiplostim treatment duration was 167 weeks (Q1, Q3: 78,227 weeks), and median average weekly dose was 5.4 µg/kg (Q1, Q3: 4.3, 8.0 µg/kg). Seven patients discontinued treatment: four withdrew consent, two were noncompliant, and one received alternative therapy. None withdrew because of adverse events (AEs). After the first 12 weeks, median platelet counts remained >50 × 109 /L. Eight (36.4%) patients received rescue medication, and 14 (63.6%) used concurrent ITP therapy. Seven patients (31.8%) reported serious AEs, and two (9.1%) reported life-threatening AEs (both thrombocytopenia); there were no serious AEs attributed to treatment and no fatalities., Conclusions: Long-term romiplostim treatment in this small cohort increased and maintained platelet counts for over 4 years in children with ITP with good tolerability and without significant toxicity. Pediatr Blood Cancer 2015;62:208-213. © 2014. The Authors. Pediatr Blood & Cancer published by Wiley Periodicals, Inc., (© 2014 The Authors. Pediatric Blood & Cancer published by Wiley Periodicals, Inc.)- Published
- 2015
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42. Immune thrombocytopenia and alopecia areata: spontaneous occurrence and resolution in the same patient.
- Author
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Cohn SM and Buchanan GR
- Subjects
- Child, Female, Humans, Alopecia Areata complications, Purpura, Thrombocytopenic, Idiopathic complications
- Abstract
Alopecia areata (AA) and immune thrombocytopenia (ITP) are autoimmune conditions occasionally encountered by pediatricians, but their simultaneous occurrence is rare. We describe here a 7-year-old female who acutely developed both AA and ITP. Within 3 months both conditions resolved spontaneously, suggesting a pathophysiologic relationship., (© 2014 Wiley Periodicals, Inc.)
- Published
- 2014
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43. Management of sickle cell disease: summary of the 2014 evidence-based report by expert panel members.
- Author
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Yawn BP, Buchanan GR, Afenyi-Annan AN, Ballas SK, Hassell KL, James AH, Jordan L, Lanzkron SM, Lottenberg R, Savage WJ, Tanabe PJ, Ware RE, Murad MH, Goldsmith JC, Ortiz E, Fulwood R, Horton A, and John-Sowah J
- Subjects
- Adolescent, Adult, Analgesics, Opioid therapeutic use, Antibiotic Prophylaxis, Child, Child, Preschool, Consensus Development Conferences as Topic, Evidence-Based Medicine, Humans, Infant, Penicillins therapeutic use, Physical Therapy Modalities, Practice Guidelines as Topic, Anemia, Sickle Cell therapy, Blood Transfusion, Hydroxyurea therapeutic use
- Abstract
Importance: Sickle cell disease (SCD) is a life-threatening genetic disorder affecting nearly 100,000 individuals in the United States and is associated with many acute and chronic complications requiring immediate medical attention. Two disease-modifying therapies, hydroxyurea and long-term blood transfusions, are available but underused., Objective: To support and expand the number of health professionals able and willing to provide care for persons with SCD., Evidence Review: Databases of MEDLINE (including in-process and other nonindexed citations), EMBASE, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, CINAHL, TOXLINE, and Scopus were searched using prespecified search terms and keywords to identify randomized clinical trials, nonrandomized intervention studies, and observational studies. Literature searches of English-language publications from 1980 with updates through April 1, 2014, addressed key questions developed by the expert panel members and methodologists., Findings: Strong recommendations for preventive services include daily oral prophylactic penicillin up to the age of 5 years, annual transcranial Doppler examinations from the ages of 2 to 16 years in those with sickle cell anemia, and long-term transfusion therapy to prevent stroke in those children with abnormal transcranial Doppler velocity (≥200 cm/s). Strong recommendations addressing acute complications include rapid initiation of opioids for treatment of severe pain associated with a vasoocclusive crisis, and use of incentive spirometry in patients hospitalized for a vasoocclusive crisis. Strong recommendations for chronic complications include use of analgesics and physical therapy for treatment of avascular necrosis, and use of angiotensin-converting enzyme inhibitor therapy for microalbuminuria in adults with SCD. Strong recommendations for children and adults with proliferative sickle cell retinopathy include referral to expert specialists for consideration of laser photocoagulation and for echocardiography to evaluate signs of pulmonary hypertension. Hydroxyurea therapy is strongly recommended for adults with 3 or more severe vasoocclusive crises during any 12-month period, with SCD pain or chronic anemia interfering with daily activities, or with severe or recurrent episodes of acute chest syndrome. A recommendation of moderate strength suggests offering treatment with hydroxyurea without regard to the presence of symptoms for infants, children, and adolescents. In persons with sickle cell anemia, preoperative transfusion therapy to increase hemoglobin levels to 10 g/dL is strongly recommended with a moderate strength recommendation to maintain sickle hemoglobin levels of less than 30% prior to the next transfusion during long-term transfusion therapy. A strong recommendation to assess iron overload is accompanied by a moderate strength recommendation to begin iron chelation therapy when indicated., Conclusions and Relevance: Hydroxyurea and transfusion therapy are strongly recommended for many individuals with SCD. Many other recommendations are based on quality of evidence that is less than high due to the paucity of clinical trials regarding screening, management, and monitoring for individuals with SCD.
- Published
- 2014
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44. Immune thrombocytopenia during childhood: new approaches to classification and management.
- Author
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Buchanan GR
- Subjects
- Female, Humans, Male, Benzoates therapeutic use, Hydrazines therapeutic use, Purpura, Thrombocytopenic, Idiopathic drug therapy, Pyrazoles therapeutic use, Receptors, Fc therapeutic use, Recombinant Fusion Proteins therapeutic use, Thrombopoietin therapeutic use
- Published
- 2014
- Full Text
- View/download PDF
45. Diagnosis and management of iron deficiency anemia.
- Author
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Powers JM and Buchanan GR
- Subjects
- Disease Management, Humans, Anemia, Iron-Deficiency diagnosis, Anemia, Iron-Deficiency therapy
- Abstract
Iron deficiency anemia (IDA) is a common hematologic condition, affecting a substantial proportion of the world's women and young children. Optimal management of IDA requires an accurate diagnosis, identification and correction of the underlying cause, provision of medicinal iron therapy, and confirmation of treatment success. There are limited data to support current treatment approaches regarding oral iron preparation, dosing, monitoring, and duration of therapy. New intravenous iron agents have improved safety profiles, which may foster their increased utilization in the treatment of patients with IDA. Clinical trials focused on improving current treatment standards for IDA are sorely needed., (Copyright © 2014 Elsevier Inc. All rights reserved.)
- Published
- 2014
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46. Practice guideline for pulmonary hypertension in sickle cell: direct evidence needed before universal adoption.
- Author
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Hassell KL, Afenyi-Annan A, Ballas SK, Buchanan GR, Eckman JR, Jordan L, Lanzkron S, Lottenberg R, and Ware R
- Subjects
- Humans, Anemia, Sickle Cell complications, Hypertension, Pulmonary diagnosis, Hypertension, Pulmonary therapy
- Published
- 2014
- Full Text
- View/download PDF
47. Burden of diagnostic radiation exposure in children with sickle cell disease.
- Author
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Vetter CL, Buchanan GR, and Quinn CT
- Subjects
- Adolescent, Adult, Child, Child, Preschool, Female, Humans, Infant, Male, Retrospective Studies, Tomography, X-Ray Computed methods, Anemia, Sickle Cell diagnostic imaging, Tomography, X-Ray Computed adverse effects
- Abstract
Children with sickle cell disease (SCD) are repeatedly exposed to diagnostic radiation. We identified 938 children with SCD who had 9,246 radiographic tests. Mean number of tests/patient was 9.9 (95% CI: 8.9-10.9) over 8,817 patient-years. Mean rate was 1.5 tests/year (95% CI: 1.3-1.6). On average, a child with SCD will have 26.7 (95% CI: 24.1-29.3) radiographic tests by 18 years of age, and 5% will have ≥100 tests. Six percent have ≥3 CT scans, which may be associated with an increased risk of cancer. Strong consideration should be given to limiting the exposure of children with SCD to radiation., (© 2014 Wiley Periodicals, Inc.)
- Published
- 2014
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48. Blood pressure abnormalities in children with sickle cell anemia.
- Author
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Becker AM, Goldberg JH, Henson M, Ahn C, Tong L, Baum M, and Buchanan GR
- Subjects
- Adolescent, Albuminuria epidemiology, Anemia, Sickle Cell physiopathology, Blood Pressure, Blood Pressure Monitoring, Ambulatory, Child, Female, Glomerular Filtration Rate, Humans, Logistic Models, Male, Prospective Studies, Anemia, Sickle Cell complications, Hypertension epidemiology
- Abstract
Background: Kidney disease is an important cause of morbidity and mortality in patients with sickle cell anemia (SCA). The factors that affect progression of renal disease are unknown, especially in children and adolescents. Alterations in blood pressure, including hypertension and lack of the normal nocturnal dip in blood pressure, are important determinants of diabetic nephropathy and other renal diseases and may play a role in sickle cell nephropathy. Our primary hypothesis was that children with SCA who have microalbuminuria will demonstrate less nocturnal dipping of blood pressure compared to patients without microalbuminuria. We also investigated other potential factors associated with microalbuminuria., Procedure: This prospective study of 52 adolescents with SCA followed in the Children's Medical Center Dallas Comprehensive Sickle Cell Center characterized 24-hour ambulatory blood pressure profiles and presence of microalbuminuria. Stepwise logistic regression was performed to identify significant independent factors that are associated with microalbuminuria., Results: Thirty-five percent of patients were identified as having previously unrecognized hypertension, and 17% had pre-hypertension (blood pressure greater than the 90th percentile but less than the 95th percentile). Fifty-six percent of patients lacked the normal nocturnal dip in blood pressure. In addition, 21% had microalbuminuria, and their percent nocturnal dip was significantly less than those without microalbuminuria (P = 0.01)., Conclusions: Blood pressure abnormalities are common in adolescents with SCA and are a possible modifiable risk factor in the progression of sickle cell nephropathy., (© 2013 Wiley Periodicals, Inc.)
- Published
- 2014
- Full Text
- View/download PDF
49. "Packaging" of fetal hemoglobin in sickle cell anemia.
- Author
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Buchanan GR
- Subjects
- Humans, Anemia, Sickle Cell immunology, Anemia, Sickle Cell therapy, Fetal Hemoglobin immunology
- Abstract
In this issue of Blood, Steinberg et al describe the clinical importance of the distribution or "packaging" of fetal hemoglobin (HbF) within erythrocytes of persons with sickle cell anemia.
- Published
- 2014
- Full Text
- View/download PDF
50. Drug-induced thrombocytopenia in children.
- Author
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Reese JA, Nguyen LP, Buchanan GR, Curtis BR, Terrell DR, Vesely SK, and George JN
- Subjects
- Adolescent, Age Distribution, Child, Child, Preschool, Humans, Infant, Infant, Newborn, Drug-Related Side Effects and Adverse Reactions epidemiology, Thrombocytopenia chemically induced
- Abstract
Background: Acute, immune-mediated thrombocytopenia may be caused by many different approved drugs as well as by other substances including vaccines, complementary and alternative medicines, herbal remedies, nutritional supplements, foods and beverages. All causes are described as drug-induced thrombocytopenia (DITP). Often the cause is not recognized, resulting in recurrent thrombocytopenia and inappropriate treatments. Systematic analysis of children (age less than 18 years) with suspected DITP has not been previously reported., Procedures: (1) We searched 15 databases to identify articles describing children with thrombocytopenia as an adverse effect of drugs and other substances. Articles were reviewed to assign levels of evidence for an association of the suspected substance with thrombocytopenia. (2) Data from the BloodCenter of Wisconsin were reviewed to identify reports of drug-dependent, platelet-reactive antibodies in children with suspected DITP., Results: Of 2,191 articles identified, 242 were selected for review. Seventy-two articles reporting 74 individual patients and nine groups of patients had evaluable data. Eleven individual patients and one group had definite evidence and 40 patients and three groups had probable evidence for an association of the suspected substance with thrombocytopenia. Thirty-two substances had a definite or probable association with thrombocytopenia. During 2008-2012, sera from 91 children with suspected DITP were tested and 21 had drug-dependent, platelet-reactive antibodies involving six substances., Conclusions: Drugs and other substances must be considered as potential causes of thrombocytopenia. Evidence from published reports and data for drug-dependent, platelet-reactive antibodies can help clinicians evaluate of children with unexpected thrombocytopenia., (© 2013 Wiley Periodicals, Inc.)
- Published
- 2013
- Full Text
- View/download PDF
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