Human Platelet Alloantigen (HPA-5) Polymorphism in Sickle Cell Disease Patients with Vaso-Occlusive Crisis

AZZA A. ALI, M.D., IMAN R. EL-MAHGOUB, M.D.;; MONA K. EL-GHAMRAWY, M.D., AMIRA S.A. FARHAN, M.Sc.;; SOHA ATEF, M.D., HEBATULLLA FAROUK, M.D.;; RANIA SOLIMAN, M.Sc., GEHAN H. SHAHIN, M.D.;

doi:10.21608/mjcu.2019.65647

Human Platelet Alloantigen (HPA-5) Polymorphism in Sickle Cell Disease Patients with Vaso-Occlusive Crisis

Document Type : Original Article

Authors

The Department of Clinical & Chemical Pathology, Faculty of Medicine, Cairo University*, National Research Centre** and Pediatric Department, Faculty of Medicine Cairo University***

10.21608/mjcu.2019.65647

Abstract

Abstract
Background: Vaso-occlusive crisis (VOC) is a significant cause of morbidity and mortality in sickle cell disease (SCD) patients. As polymorphisms in human platelet antigens (HPA) exhibit a prothrombotic nature, we hypothesized that specific HPA polymorphisms could have a role in the pathogenesis of VOC in SCD.
Aim of Study: This study investigated HPA-5 G1648A polymorphism among Egyptian SCD patients.
Patients and Methods: This study included 100 SCD patients and 50 controls. Patients were divided into, VOC group (n=60), and steady-state group (n=40). Genotyping was done using PCR-based Restriction Fragment Length Polymor-phism (RFLP) technique.
Results: The HPA-5 mutant genotypes were significantly associated with SCD compared to controls (p=0.003), while no significant difference was observed between VOC and steady-state groups (p=0.179). Regarding the frequency of VOC episodes, the HPA-5 homozygous mutant genotypes showed significant differences (p=0.003). Regarding VOC complications, the HPA-5b/5b genotype was significantly associated with acute chest syndrome only (p=0.021).
Conclusion: The HPA-5 G1648A polymorphism is common among SCD patients. Although neither of them is a major determinant of vasculo-cclusion in SCD, they are significantly associated with VOC complications and may alter their outcome.

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