;Study of Genotype / Phenotype Pattern in Egyptian Patients with Sickle Cell Disease

Abstract

SUMMARY ickle cell disease is used to refer to all the different genotypes that cause the characteristic clinical syndrome.The mutation in beta globin gene is insufficient to account for the phenotypic differences among patients; other genes known as pleiotropic or secondary effectors genes are likely to modulate its phenotype. This study aimed to evaluate the genotype of patients with sickle cell disease in relation to the different clinical presentations of the disease, the episodes of vasocclusive crises and the occurrence of morbidties and mortality. All included patients were subjected to detailed medical history including, Onset of the disease, transfusion history (type, interval between transfusion, transfusion index) chelation and hydroxyurea therapy and compliance in last 2 years. Collection of data from medical records: baseline CBC(Hb%, MCV), HbF%, mean pretranfusion hemoglobin level,with calculation of mean serum ferritin in last 2 years,data of cardiac, renal, cerebral, hepatic morbidities as well as frequency of pain episodes, and hospitalization, percentage of patients who suffered from acute chest syndrome and avascular necrosis, Echocardiographic, carotid doppler findings. Genotyping for the detection of beta-thalassemia mutations was performed based on polymerase chain reaction (PCR) and reverse hybridization. S Summary 107 This study included 38 sickle cell patients (21 male and 17 female) who are regularly attending the hematology/oncology clinic Children hospital Ain Shams University in the period from September 2013 to September 2014. Eighty percent of our studied Sickle cell patients had Acute painful episodes, 18% suffered from at least one attack of acute chest syndrome, 5.3% had avascular necrosis of femur 15.8% had single episode of stroke while 6% had cardiac morbidity, 13% had impaired left ventricular contractility, (8%) had cardiomyopathy, and none had pulmonary hypertension We found significantly positive correlation between HbF and transfusion index while we found no correlation between HbF and interval between transfusion pretransfusion hemoglobin, frequency of pain episodes, acute chest syndrome, stroke and sickling score. We found that sickle cell patients on Hydroxyurea treatment had significantly lower transfusion index than those not onHydroxyurea treatment or had poor compliance. We found significantly positive correlation between mean serum ferritin and frequency of pain episodes. In the current study, 66% of genotyping among sickle cell patients was S/S homozygote Codon 6, 18% Codon 6[A>T] HbS / β̊ IVS1-1[G>A],8% Codon 6[A>T] HbS / β+ IVS1-110[G>A] and the least common were Codon 6[A>T] Summary