Renal Disease in b-Thalassemia. Is there a Relation to ApoE Gene Polymorphism? A Study in b-Thalassemia Egyptian Patients

Background: b -thalassemia is acommon haemolytic anaemia in Egypt. Renal complicationsare an underestimated problem of b -thalassemia. Renal injury has been attributed to the anaemia, the haemolysis, iron overload, or iron chelators. ApoE gene polymorphism has been studied in many settings in b -thalassemia. Aim of Study: In our study, we aimed to examine the possible relation of ApoE gene polymorphism to renal disease in b -thalassemia patientsand whether the APO E4 allele can be a potential genetic risk factor for the development of proteinuria in that population. Patients and Methods: Forty patients with b -thalassemia were recruited from the Internal Medicine outpatient clinic at the Kasr Al-Ainy Hospital, Cairo University and compared to 45 healthy control subjects, age and sex-matched. b - thalassemia patients were further subdivided in two group. Group I with ACR less than 30 m g/mg (20 patients) and group II with ACR more than or equal 30 m g/mg (20 patients). ApoE Polymorphisms genotyping was performed by Polymerase Chain Reaction Restriction Fragment Length Polymorphism (PCR-RFLP). Results: Our results showed that there was a statistically significant difference between cases and control regarding serum creatinine, eGFR and ACR. The distribution of ApoEin b -thalassemia cases is E2/E3 10%, E3/E3 87.5% and E3/E4 2.5% and in control is E2/E3 4.4%, E3/E3 88.9% and E3/E4 6.7% with a statistically significant difference ( p -value <0.001). Conclusion: Our study demonstrated a significant differ- ence in eGFR, Albumin Creatinine Ratio and ApoE genotyping between b -thalassemia cases and control. Although the distribution of ApoEin b -thalassemia cases is statistically different from control, it was not correlated to eGFR or proteinuria.