Search

BACKGROUND: Adolescent and young adult (AYA) women with sickle cell disease (SCD) have increased pregnancy-related health risks and are prescribed potentially teratogenic medications, yet limited data are available regarding pediatric SCD provider contraceptive practices. We aimed to assess pediatric hematology providers’ beliefs, practices, motivators, and barriers for providing contraceptive care to female AYA with SCD. METHODS: Guided by the Health Belief Model (HBM), we developed a 25-question, web-based survey to assess practices. Survey links were distributed nation-wide to pediatric SCD and/or general hematology providers through their publicly available emails and by request to directors of U.S. accredited Pediatric Hematology-Oncology fellowship programs for distribution to their SCD providers. Data analysis included descriptive statistics, chi-square analysis, logistic regression. RESULTS: Of 177 respondents, 160 surveys meeting inclusion criteria were analyzed. Most providers reported counseling (77.5%) and referring female AYA patients for contraception (90.8%), but fewer reported prescribing contraception (41.8%). Proportionally fewer trainees provided counseling compared to established providers (54% vs. 85%, p

BACKGROUND Food insecurity and housing instability, both social determinants of health (SDoH), disproportionately affect economically unstable, under-resourced US communities in which children with sickle cell disease (SCD) live. Association between these SDoH markers and dietary quality among children with SCD is unknown. PROCEDURES We assessed a cross-sectional sample of dyadic parent-child patients and young adult patients up to age 21 from one pediatric SCD center. Food insecurity, housing instability, and dietary quality were measured using validated US instruments and a food frequency questionnaire. Better dietary quality was defined using US dietary guidelines. Multivariate regression assessed for associations among dietary quality and food insecurity with or without (±) housing instability and housing instability alone. RESULTS Of 100 enrolled participants, 53% were Black and 43% Hispanic; mean age 10.6 ± 5.6 years. Overall, 70% reported less than or equal to one economic instability: 40% housing instability alone and 30% both food insecurity and housing instability. Eighty percent received more than or equal to one federal food assistance benefit. Compared to no economic instability, food insecurity ± housing instability was significantly associated with higher intake of higher dairy and pizza, while housing instability alone was significantly associated with higher dairy intake. Food insecurity ± housing instability was significantly associated with lower intake of whole grains compared to housing instability alone. CONCLUSIONS Our sample reported high frequencies of both food insecurity and housing instability; having more than or equal to one SDoH was associated with elements of poorer diet quality. Screening families of children with SCD for food insecurity and housing instability may identify those with potential nutrition-related social needs.

To identify people living with sickle cell disease (SCD) and study their healthcare utilization, researchers can either use clinical records linked to administrative data or use billing diagnosis codes in stand-alone administrative databases. Correct identification of individuals clinically managed for SCD using diagnosis codes in claims databases is limited by the accuracy of billing codes in outpatient encounters. In this critical review, we assess the strengths and limitations of claims-based SCD case-finding algorithms in stand-alone administrative databases that contain both inpatient and outpatient records. Validation studies conducted using clinical records and newborn screening for confirmation of SCD case status have found that algorithms that require three or more nonpharmacy claims or one inpatient claim plus two or more outpatient claims with SCD codes show acceptable accuracy (positive predictive value and sensitivity) in children and adolescents. Future studies might seek to assess the accuracy of case-finding algorithms over the lifespan.

AIM We aimed to assess the receipt of recommended care for young children with sickle cell disease (SCD) in a central SCD clinic in Kampala Uganda, focusing on standard vaccination and antibacterial and antimalarial prophylaxis. METHODS A cross-sectional assessment of immunisation status and timeliness and prescribed antibacterial and antimalarial prophylaxis was performed in a sample with SCD aged ≤71 months in Mulago Hospital SCD Clinic. Government-issued immunisation cards and clinic-issued visit records for prescribed prophylaxis were reviewed. RESULTS Vaccinations were documented by immunisation cards in 104 patients, mean age 31.7 months (range 3-70 months). Only 48 (46.2%) received all doses of each of the four recommended vaccine types, including pneumococcal 10-valent conjugate vaccine (pneumococcal conjugate vaccine (PCV)-10), which became available in 2014. Vaccination completion was associated with younger age and, for polio, maternal employment. PCV-10 series was completed in 54.8% of the sample and in 18.2% of those aged 48-71 months. Of children completing all vaccination types, an average 68.8% were immunised on time, defined as

Background Hydroxyurea (HU) induces dose-dependent increased fetal hemoglobin (HbF) for sickle cell disease (SCD). Large deviation from historical personal best (PBest) HbF, a clinic-based version of maximum dose, may identify a subset with suboptimal HU adherence over time. Procedure Retrospective clinical data from youth ages 10–18 years prescribed HU at two centers were extracted from medical records at three time points: pre-HU initiation, PBest and a recent assessment. Decrease from PBest HbF of 20% or more at recent assessment despite stable dosing was designated as high deviation from PBest. Acute hospital use was compared between 1-year periods, pre-HU and ±6 months for PBest and recent assessment. Groups were compared using descriptive and bivariate nonparametric statistics. Results Seventy-five youth, mean HU duration 5.9 years, met eligibility criteria. Mean ages of HU initiation, PBest and recent assessment were 8.0, 10.9 and 13.9 years, respectively. Despite stable dosing, average HbF of 19.5% at PBest overall declined by 31.8% at recent assessment. PBest HbF declined by 11.7 and 40.1% in two groups, the latter comprised 70.7% of the sample, had lower pre-HU and recent HbF and higher dosing. They experienced more urgent hospital use during the year framing recent assessment than during PBest; these findings were supported by sensitivity analysis. Conclusions Decline from PBest HbF is a novel approach to assess HU effectiveness, is common among youth and may represent suboptimal adherence. Larger prospective studies using additional adherence measures are needed to confirm our approach of tracking HbF deviation over time and to define an appropriate cutoff.

Hydroxyurea (HU) is a crucial therapy for children with sickle cell anemia, but its off-label use is a barrier to widespread acceptance. We found HU exposure is not significantly altered by liquid vs capsule formulation, and weight-based dosing schemes provide consistent exposure. HU is recommended for all children starting as young as 9 months of age with sickle cell anemia (SCA; HbSS and HbSβspan(0) thalassemia); however; a paucity of pediatric data exists regarding the pharmacokinetics (PK) or the exposure-response relationship of HU. This trial aimed to characterize the PK of HU in children and to evaluate and compare the bioavailability of a liquid vs capsule formulation. This multicenter; prospective; open-label trial enrolled 39 children with SCA who provided 682 plasma samples for PK analysis following administration of HU. Noncompartmental and population PK models are described. We report that liquid and capsule formulations of HU are bioequivalent; weight-based dosing schemes provide consistent drug exposure; and age-based dosing schemes are unnecessary. These data support the use of liquid HU in children unable to swallow capsules and in those whose weight precludes the use of fixed capsule formulations. Taken with existing safety and efficacy literature; these findings should encourage the use of HU across the spectrum of age and weight in children with SCA; and they should facilitate the expanded use of HU as recommended in the National Heart; Lung; and Blood Institute guidelines for individuals with SCA.

Latin Americans are an underappreciated population affected by sickle cell disease (SCD). Sickle trait and SCD exist throughout Latin America and U.S. Latino communities. We describe the epidemiology and genetic heterogeneity of SCD among Latin Americans, and fetal hemoglobin expression. National population-based newborn screening for SCD is limited to Brazil, Costa Rica, and the U.S. Available and extrapolated data suggest that over 6,000 annual births and 100,000-150,000 Latin Americans are affected by SCD. This comprehensive review highlights the substantial numbers and population distribution of SCD and sickle trait in Latin America, and where national newborn screening programs for SCD exist.

Background Use of hydroxyurea (HU) in children with sickle cell disease (SCD) may be hampered by its formulation as a capsule and the limited availability of liquid HU. Procedure At four Pediatric SCD clinics, parents of children with SCD ages 5–17 years were surveyed about their children's medication use and ability to swallow medication. Data were stratified by HU therapy and analyzed using descriptive statistics, Chi square tests, Fisher exact tests and univariate analysis. Results Of the 116 parents surveyed, 97% were the primary caregiver. One fourth (26%) of parents reported that their child's difficulty swallowing medication interfered with daily medication use. Age-related differences were found in ability to swallow medication, but not by HU use. Children taking HU were more likely to take multiple daily medications, with more frequent dosing schedules. Among 65 HU users, children using the liquid formulation (28%, n = 18) were younger than capsule users (P

Background Hydroxyurea (HU) is highly effective treatment for Sickle Cell Disease (SCD). While pediatric use of HU is accepted clinical practice, barriers to use may impede its potential benefit.

Fetal hemoglobin (HbF) levels are generally inversely proportional to severity of sickle cell disease (SCD) for given sickle phenotypes. Molecular regulation of HbF occurs through complex interactions cis and trans to the beta globin gene locus. Novel insights made through population-based genetic epidemiologic studies of non-anemic populations were replicated in SCD groups, despite large differences in HbF levels. Identification of the lymphoid transcription factor BCL11A as a key suppressor of HbF expression validates approaches using population genetics to study HbF expression. We review these methods and findings, and speculate on applying pharmaco-genetics to optimize hydroxyurea therapy aimed at increasing HbF.

The term "pilot study" has been used over the years to describe the evaluation of the many elements involved in deciding whether a proposed condition should be added to a newborn screening (NBS) panel, and until recently, was unilaterally used to describe the evaluation of the assay to be used before the condition was officially adopted by a state for its newborn screening panel. Since Guthrie's introduction of screening for PKU, each time a new condition was added to the panel, the screening assay itself was validated through a population-based trial, in which the test was performed with de-identified samples to avoid association between the test result and the infant. This is considered by the laboratory as the "pilot phase" of adding a new condition. To advance the science of NBS, especially to accommodate new technologies that may provide new types of information (genetic versus physiological) for each new condition, pilot programs are essential. Involvement of the clinical community serves to improve these evaluations and provides the needed clinical validation of decisions made as a result of it. This paper describes the historical context of pilot programs in population-based NBS that utilize laboratory-based markers as indicators of concern; specifically, three applications that demonstrate different approaches to the use of pilots in adding conditions to a NBS panel are described.

In the course of an immune response, antibodies undergo affinity maturation in order to increase their efficiency in neutralizing foreign invaders. Affinity maturation occurs by the introduction of multiple point mutations in the variable region gene that encodes the antigen binding site. This somatic hypermutation is restricted to immunoglobulin genes and occurs at very high rates. The precise molecular basis of this process remains obscure. However, recent studies using a variety of in vivo and in vitro systems have revealed important regulatory regions, base motifs that are preferred targets of mutation and evidence that transcription may play an active role in hypermutation.

We have established B cell culture systems in which transfected and stably integrated Ig constructs spontaneously undergo high rates of variable (V) region mutation. Mutation rates were determined using reversion analysis of an Ig V region nonsense codon (Vn). A construct (Vn/gamma2a) in which a Vn was associated with the gamma2a constant region and its intervening and immediate flanking sequences mutated at a high rate of 2.2 x 10(-4)/bp/generation in the NSO myeloma cell line. This same Vn, when associated with the mu constant region (Vn/mu), mutated at a 1000-fold lower rate in NSO. The Vn/gamma2a construct also mutated at high rates in the 18.81 pre-B and the S107 myeloma cell lines and at a low rate in the J558 myeloma cell line. In NSO, the presence of the gamma2a construct raised the mutation rate of the mu construct and the mu decreased the mutation rate of gamma2a. These results suggest that there is both positive and negative regulation of V region mutation and that different cell lines express different combinations and/or amounts of trans-acting factors that are involved in the mutational process.