Search

Objectives: To study and classify the immunophenotypic characteristics of Omani patients diagnosed with T-cell acute lymphoblastic leukemia (T-ALL) and to correlate the results with age and gender as well as biological factors (peripheral and bone marrow blast cells percentage). Methods: Fifty cases from both genders and of all ages who fulfilled the inclusion criteria with a diagnosis of T-ALL were included in the study. Correlation of T-ALL subtypes with age, gender, and initial bone marrow and peripheral blood blast cells percentage was assessed using ANOVA. Results: Among the 50 T-ALL patients analyzed, 44 were male and six were female giving a male-to-female ratio of 7:1 (p = 0.007). The average age of patients was 19.2 years with no significant differences in the three disease subtypes. No significant association was seen between the peripheral or bone marrow blast cell percentage and the differentiation stages of the neoplastic clone of T-ALL. All female patients were found to express an immature T-ALL phenotype. Conclusions: This study reports the subtypes of T-ALL in Oman for the first time. It is hoped that this will lead to a better understanding of the disease outcomes.

Objectives: To estimate the incidence, risk factors, and outcome of cytomegalovirus (CMV) infection during the first year following hematopoietic stem cell transplant (HSCT) among Omani patients. Methods: This retrospective study included allogenic HSCT recipients between January 2006 and December 2018. We investigated the possible factors associated with CMV infection and CMV impact on one-year mortality.Results: Among 556 recipients of allogenic HSCT, 308 (55.4%) were male, the median age was 12 years, and 366 (65.8%) had benign conditions. One-year after transplants, the prevalence of CMV infection was 59.4%, and that of CMV disease was 1.8%. Multivariate analyses revealed significant relationships between CMV infection and haploidentical transplant (p =0.006), graft versus host disease (p =0.013), myeloablative conditioning (p =0.001), and patient age ≥ 12 years (p < 0.001). CMV infection was associated with an increased risk of one-year mortality (p =0.001). One-year overall mortality was 8.3%. Conclusions: The incidence of CMV infection in this Omani cohort was comparable with earlier findings, but the disease incidence and overall mortality were lower. Older age, haploidentical transplant, myeloablative conditioning, and graft versus host disease were significantly associated with a higher risk of CMV infection. In addition, CMV infection was associated with an increased risk of overall mortality in the first year post-transplant. Our findings support early initiation of preemptive therapy at low-level CMV viremia.

Objectives: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most encountered abnormality of red blood cell metabolism worldwide and has a high prevalence in Oman. The objective of the study was to characterize the mutation variants of G6PD deficiency in a cohort of the Omani population with partial and complete enzyme deficiency. Methods: This prospective study included newborns and children less than one year of age with partial or complete G6PD enzyme deficiency identified on routine screening using a fluorescent spot test from 31 January 2017 to 12 September 2017 in Sultan Qaboos University Hospital. The identified samples were analyzed for the presence of C563T, G1003A, and other mutations using direct DNA sequencing of the polymerase chain reaction. Results: Out of 3679 newborn samples screened, 21.0% were found to have complete or partial G6PD enzyme deficiency. A total of 145 participants were included in the genetic analysis, of which 133 (91.7%) were completely deficient in G6PD enzyme activity and 12 (8.3%) had partial deficiency. The Mediterranean variant (C563T) was identified in 129 (89.0%). Other variants were found as follows: eight (5.5%) had variant A-, three (2.1%) had the Chatham variant (G1003A), one (0.7%) had the Cosenza variant, and one (0.7%) had exon 11 variant. No mutation was found in two subjects. Conclusions: The most common mutation in the Omani population is the Mediterranean mutation (C563T) followed by the variant A- mutation. However, not all participants were found to have a mutation.

A systematic review is a specific and reproducible method to search, identify, select, appraise, and summarize all studies relevant to a particular health care question. In this paper, we will review the concept of level of evidence, define the terms systematic review and meta-analysis, and outline the steps in performing a systematic review and meta-analysis with an illustrative example. We will also introduce some important concepts in systematic reviews and meta-analyses like heterogeneity, publication bias, forest plots, and quality assessment. Finally, this review will focus on systematic reviews addressing therapeutic research questions.

Acquired thrombotic thrombocytopenic purpura (aTTP) is a rare hematological emergency characterized by microangiopathic hemolytic anemia, thrombocytopenia, fever, and multiorgan failure due to autoimmune-mediated deficiency in ADAMTS-13 activity. Currently, plasma exchange, with or without steroids, is the frontline option for the management of aTTP. The treatment should be started promptly once the disorder is clinically suspected. Besides, immunomodulators were studied in patients with aTTP to achieve stable remission and reduce the risk of relapse in patients with suboptimal response to plasma exchange; however, clinical trials showed equivocal results. Published data on early diagnosis, referral, and treatment patterns of aTTP patients in the member nations of the Arabian Gulf Cooperation Council (GCC) are still lacking. Therefore, the present consensus report aimed to present an overview of aTTP situation in GCC by bringing together a panel of experts from three GCC nations, to share their views on current trends and practices regarding aTTP. The experts discussed challenges including the lack of reliable data regarding the incidence of aTTP in GCC and delayed results of ADAMTS-13 activity testing. Limited patient access to tertiary centers and low level of awareness about the aTTP clinical spectrum among general practitioners are other challenges. The experts agreed that there is a need for national and regional consensus regarding the diagnosis and treatment of aTTP in the Gulf region.

We aimed to estimate the nature and prevalence of paroxysmal nocturnal hemoglobinuria (PNH) among Omani patients. We performed a retrospective review of all patients who were tested for PNH by flow cytometry at the Sultan Qaboos University Hospital, Muscat, between 2012 and 2019. Manifestations, treatment modalities, and outcomes were assessed. A total of 10 patients were diagnosed or were on follow-up for PNH (median age 22.5 years). Clinical manifestations included fatigue (80%) and anemia (70%). Six patients had classical PNH with hemolysis, three had PNH in the context of aplastic anemia, and one patient had subclinical PNH. The median total clone size (type II + III) for neutrophils was 95.5 (range: 1.5–97) (FLAER/CD24) and for monocytes was 91.6 (range = 0.04–99) (FLAER/CD14). Four patients had clone sizes > 50% at the time of diagnosis. The median follow-up period of the patients was 62 months (range = 8–204 months). One patient suffered thrombosis. Three patients were on immunosuppressant agents, five were initiated on eculizumab, and four had a bone marrow transplant. No deaths were reported in the cohort. The estimated average incidence of PNH among Omani patients was 1.5 per 5 000 000. PNH is rare in the Omani population. The predominant presentation is hemolytic anemia.

Objectives: Most literature on the frequencies of red blood cell (RBC) phenotypes are published in Europeans and Africans countries, with the frequencies in the Omani population unknown. We sought to determine the prevalence of RBC blood group phenotypes among Omani blood donors. Methods: Blood group ABO, RhD type, and phenotyping were performed for 21 blood group antigens on enrolled blood donors. The following antigens were assessed serologically: Rh (C, c, E, e), Kell (K, k, Kpa, Kpb), Kidd (Jka, Jkb), Duffy (Fya, Fyb), Lewis (Lea, Leb), Lutheran (Lua, Lub), MNS (M, N, S, s), and P1. Results: A total of 337 Omani blood donors were tested. The most common blood group was O+ (44.9%). Among the tested blood donors studied, 89.3% were RhD positive with R1r being the most common Rh phenotype. The k antigen was found at a frequency of 99.4%, while 4.5% of the blood donors studied were K+. The most common phenotype in the Duffy blood group system was Fy(a-b-), while the most common phenotypes in the Kidd and MNS blood group systems were Jk(a+b+) and M+N-S+s+ at 47.0% and 22.6%, respectively. The Le(a+) and Le(b+) antigens were found in 21.7% and 67.3% of the blood donors, respectively. One Jk(a-b-), one Le(a+b+), and two Lu(a-b-) individuals were identified. Conclusion: This is the first study to examine the frequencies of RBC phenotypes among the Omani blood donors. The study’s results show Duffy blood group frequencies that resemble what has been reported in the African population, and higher frequencies of the rare null phenotypes compared to European populations.

Objectives: Cerebral venous sinus thrombosis (CVST) is a disease with potentially serious consequences. The clinical presentation and outcomes of these patients have not been described in Oman. We sought to describe the clinical characteristics and outcomes of patients with CVST. Methods: We conducted a retrospective study in two tertiary care centers in Oman, which included all Omani adults with radiologically confirmed CVST. We recorded and analyzed patients’ demographic, clinical, and outcome data. Results: Fifty-four patients had radiologically confirmed CVST. The commonest presenting feature was headache (85.0%), followed by focal motor deficits (48.0%) and seizures (27.0%). In this cohort, 24.0% were pregnant or postpartum, 11.0% had an inherited thrombophilia, 11.0% were on hormonal therapy, and 11.0% had systemic lupus erythematous; 38.9% of patients had multiple sinus thrombosis while 35.2% had sigmoid and transverse sinus thrombosis. Antiphospholipid antibody syndrome and infection accounted for 7.0% and 13.0% of causes, respectively, while cancer accounted for 2.0%. No cause was identified in 33.0% of cases. Only 1.9% of patients died, while 29.6% had a residual neurological deficit at hospital discharge. Age was a predictor for residual neurological deficit (p =0.003). Conclusions: Pregnancy and postpartum were the most common predisposing factors for CVST in our cohort. Although the mortality rate is low, the risk of residual neurological deficit remains high. We recommend a prospective study for better characterization and outcome assessment.

Objectives: We sought to determine the prevalence, pattern of causative organisms, and mortality of newborns with culture-proven late-onset sepsis (LOS) and to determine and compare the risk factors linked to late-onset gram-positive and late-onset gram-negative sepsis in Sultan Qaboos University Hospital (SQUH). Methods: We conducted a cross-sectional retrospective study of data obtained between 1 January 2007 and 31 December 2014 (eight years) from infants in the neonatal intensive care unit (NICU) at SQUH. Infants born in SQUH (inborn) and other institutions (outborn) with positive blood cultures were included in the study. Results: The total number of live births and admissions during the study period were 26 289 and 3559, respectively. The total number of infants identified with LOS were 125 of whom 69 (55.2%) were gram-positive, 52 (41.6%) were gram-negative, and four (3.2%) were due to Candida species (spp.). The majority of infants (n = 113, 90.4%) were inborn; 69 (55.2%) were males and 56 (44.8%) were females. The prevalence of LOS among inborn admissions was 4.3 per 1000 live births. Most infections occurred in very low birth weight infants (n = 81, 64.8%). Eleven (8.8%) infants died due to gram-negative sepsis. Klebsiella pneumoniae followed by Pseudomonas aeruginosa were the leading cause of death. Maternal intrapartum antibiotics were the only independent risk factor correlating with gram-negative organisms in multivariate analysis (p = 0.003). Conclusions: LOS poses a burden in the NICU, which could be due to the increasing survival of premature babies. The main contributing organisms to LOS are gram-positive bacteria. Klebsiella spp. is a major cause of mortality in LOS. The use of intrapartum antibiotic prophylaxis in mothers might explain the positive correlation of maternal antibiotics as a risk factor with gram-negative infections.

Objectives: Increased cardiac troponin I (TI) has been suggested to be a sensitive indicator of intraoperative myocardial injury. We investigated the association of transfusion on TI levels post-surgery and outcomes in patients undergoing elective cardiac surgeries. Methods: We conducted a retrospective review of 542 patients. Patients were divided into two groups based on TI levels at 24 hours (TI24) (> 6.5 µg/L vs. ≤ 6.5 µg/L). The impact of transfusion on TI levels was estimated using logistic regression and adjusted for using a multivariable model that included aortic cross-clamp time and preoperative ejection fraction. The effect of TI on the clinical outcomes was examined. Results: Red blood cell (RBC) transfusion was found to be associated with high TI levels (odds ratio (OR) = 2.33, p = 0.007, 95% confidence interval (CI): 1.30–4.30). A trend was observed when aortic cross-clamp time and preoperative ejection fraction were adjusted for (OR = 2.06, p = 0.080, 95% CI: 0.90–4.70). An association was found between aortic cross-clamp time and high TI levels in the multivariable model (OR = 1.01, p = 0.028, 95% CI: 1.00–1.02). Elevated TI levels was associated with higher mortality (OR = 4.15, p = 0.017, 95% CI: 1.29–13.08), renal failure (OR = 2.99, p = 0.004, 95% CI: 1.41–6.32), and increased length of stay in-hospital (OR = 4.50, p = 0.020, 95% CI: 0.69–8.30). Conclusions: RBC transfusion is associated with increased TI24 post-cardiac surgery and worse outcomes, albeit a confounding effect cannot be excluded. Larger studies are required to confirm these findings.

Objectives: To evaluate the impact of myeloid antigen expression on complete remission (CR), event-free survival (EFS), and overall survival (OS) in patients with T-cell acute lymphoblastic leukemia (T-ALL) treated with intensive chemotherapy. Methods: We retrospectively reviewed consecutive patients diagnosed with T-ALL and treated in Sultan Qaboos University Hospital and Royal Hospital in Oman between 2004 and 2010. The diagnosis of T-ALL was established using French-American-British classification or World Health Organization criteria. Patients were considered having myeloid antigen expression if they expressed CD13, CD33, or both (My+ and My–). Results: Of the 39 patients, 38 were included in the study (25 patients with My– and median age of 18.4 years, 13 patients with My+ and median age of 22.0 years). Median follow-up was 12 months. Thirty-two out of the total cohort were eligible for response-rate assessment. Twenty-nine patients (90.6%) achieved CR with one or two courses of chemotherapy with similar CR rates between the two groups (p = 0.880). Twenty-five percent (5/20) of the patients with My– required two courses of induction, whereas 58.3% (7/12) of My+ required two courses of induction and the difference was statistically significant (p = 0.040). In the multivariable analysis; age, gender, initial white blood cell count, central nervous system disease, and myeloid antigen expression were not statistically significant predictors of CR. The EFS and OS were similar between the My+ and My– groups p = 0.180 and p = 0.440, respectively. Conclusions: Patients with T-ALL with myeloid antigen expression need more courses of induction; however, rates of CR, EFS, and OS are not different from those without myeloid antigen expression. Larger prospective studies are required to confirm these findings.

Objectives: Transfusion is a common intervention that mandates the discussion of benefits, risks, and alternatives to planned transfusions. In Oman, transfusion consent was first introduced at the Sultan Qaboos University Hospital in March 2014. We sought to evaluate our physicians’ opinions, attitudes, and perception of the transfusion consent process. Methods: Attending physicians of different specialties were invited to complete an anonymous survey on transfusion consent. Results: A total of 114 physicians responded to the survey. Transfusion benefits and risks were explained regularly by 91% and 87% of the surveyed physicians, respectively. On the other hand, alternatives were declared by only 38%. Discomfort with the consent process was admitted by 10% of the physicians. There was no statistically significant association between discomfort in obtaining the consent and the physician seniority (p = 0.801), nor their specialties (p = 0.623). The importance of the consent process was acknowledged by 80% of surveyed physicians, who supported its implementation in other hospitals. Conclusion: This survey reflects positive attitudes of the surveyed physicians on the importance of transfusion consent. However, actions are required to achieve physicians’ full ease with the process and to ensure that transfusion alternatives are discussed. We advocate implementation of transfusion consent in other hospitals in Oman.

Objectives: To assess the response rate and duration of response in patients with chronic immune thrombocytopenia (ITP) receiving rituximab. Methods: We retrospectively analyzed 32 consecutive patients with chronic ITP who were treated in two tertiary centers in Oman. Response assessment was based on the American Society of Hematology criteria. Results: Nineteen patients (59%) had an initial response. However, six of the 19 patients lost their response leaving 13 patients with long-lasting remissions. The median age at diagnosis was 25 years (range 14–58). The median time from diagnosis to rituximab therapy was 21 months. The median follow-up after starting rituximab was 26 months. The overall cumulative response rate was 59% (complete response 44%, partial response 15%) and the median time to respond was 30 days with a response rate of 44% at four weeks. In all responders, the cumulative rate of loss of response was 32% with a median time to lose response of 54 months. Conclusions: The use of rituximab in ITP achieves high response rate and long remission duration. Our study was limited by the small sample size and further larger prospective studies are recommended.

Objective: This study aims to evaluate the knowledge and attitudes of Oman Medical Specialty Board (OMSB) residents towards Evidence-Based Medicine (EBM). Methods: This cross sectional study was conducted on all OMSB residents through a self-administered online questionnaire between October 2012 and March 2013. An electronic survey was designed to identify and determine residents' knowledge and attitudes toward the use of EBM. Results: The survey was completed by 93 (21%) OMSB residents, 76 (82%) of whom took part in continuing education courses and 50 (54%) belonged to professional practice-oriented organizations. On average, the residents were reportedly involved in patient care for approximately 70% (Standard Deviation [SD] 17%) of their time, while 14% (SD 12%) participated in research activities. The results showed that 53 respondents (57%) were competent users of medical search engines compared to 23 residents (25%) who rated their skills as neutral. Sixteen percent of the respondents strongly agreed and 46% only agreed that the facility supports the use of current research in practice. Fourteen percent strongly agreed and fifty-three percent only agreed that the foundation of EBM is part of OMSB academic preparation. On the other hand, 17% of the respondents thought that insufficient time is always a barrier against EBM, while another 27% perceived insufficient time as a usual barrier. The lack of information resources was reported to always be a barrier in 11% of the respondents while 32% thought that it usually acts as a barrier. Conclusion: Time constraints and skills in EBM were found to be the two major obstacles. This study was, however, limited by the low response rate of the survey; thus larger studies with a previously validated questionnaire should be conducted in the future.

Objectives: Chelating agents remain the mainstay in reducing the iron burden and extending patient survival in homozygous beta-thalassemia but adverse and toxic effects may increase with the institution and long term use of this essential therapy. This study aimed to estimate the incidence of deferasirox (DFX) side effects in patients with thalassemia major or intermedia.Methods: A retrospective study of 72 patients (mean age: 20.3±0.9 yrs; 36 male, 36 female) with thalassemia major or intermedia treated at Sultan Qaboos University Hospital, Oman, was performed to assess the incidence of side effects related to deferasirox over a mean of 16.7 month follow-up period.Results: Six patients experienced rashes and 6 had gastro-intestinal upset. DFX was discontinued in 18 patients for the following reasons: persistent progressive rise(s) in serum creatinine (7 patients; 40% mean serum creatinine rise from baseline), feeling unwell (2), severe diarrhea (1), pregnancy (1), death unrelated to chelator (2) and rise in serum transaminases (2). Three patients were reverted to desferoxamine and deferiprone combination therapy as DFX was no longer biochemically effective after 18 months of therapy. There was no correlation between baseline serum ferritin and serum creatinine or a rise in serum creatinine. Cardiac MRI T2* did not change with DFX therapy. However, there was an improvement in liver MRI T2* (p=0.013).Conclusion: Renal side effects related to deferasirox appear to be higher than those reported in published clinical trials. Further larger studies are required to confirm these findings.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked genetic disorder characterized by low levels of the G6PD enzyme. It is present worldwide but with more prevalence in the Middle East and the Mediterranean areas. We report a case of severe hemolysis due to G6PD deficiency manifesting as methemoglobinemia in a 70 year old Omani male never known to have any previous hemolytic episodes or previously diagnosed of G6PD deficiency.

We report here four cases of genital ulcers that developed after the administration of all-trans retinoic acid (ATRA) for the treatment of acute promyelocytic leukemia (APL). Between October 2007 and March 2010, three males and one female (age range 19-35 years) were identified to have genital ulcers after being prescribed all-trans retinoic acid (ATRA) as a part of chemotherapy for APL. This is the first series of cases describing genital ulcers, as a unique and rare complication of ATRA used for treatment of APL in these patients, with no other cause identified. Following temporary cessation of ATRA for a few days in these three cases, improvement of the ulcers was noted.