Endothelin-1 gene polymorphism (G8002A) and endothelial monocyte-activating polypeptide II: Role in vascular dysfunction in pediatric patients with ß-thalassemia major.

BACKGROUND: Endothelin-1 (ET-1), a potent endogenous vasoconstrictor, stimulates production of reactive oxygen species. Endothelial monocyte-activating polypeptide-II (EMAP-II) is a multifunctional polypeptide. AIM: To assess ET-1 gene polymorphism (G8002A) in pediatric patients with ß-thalassemia major (ß-TM) as a potential genetic marker for vascular dysfunction and its possible relation to EMAP II, oxidative stress and vascular complications. METHODS: ß-TM patients (n = 95) without symptomatic cardiac or renal disease were compared with 95 healthy controls. Markers of hemolysis, serum ferritin, urinary albumin-to-creatinine ratio, serum EMAP II, malondialdehyde (MDA) and antioxidant enzymes; superoxide dismutase (SOD), glutathione peroxidase (GPx), reduced glutathione (GSH), glutathione reductase and catalase were measured. ET-1 gene polymorphism (G8002A) was determined using polymerase chain reaction­restriction fragment length polymorphism. RESULTS: ß-TM patients had significantly higher EMAP II than healthy controls. EMAP II was significantly higher among patients with cardiac disease, pulmonary hypertension (PH) risk, nephropathy, poor compliance to therapy and ferritin ≥ 2500 µg/L. There were significant correlations between EMAP II and transfusion index, LDH, ferritin and oxidative stress markers. The AA genotype of ET-1 gene polymorphism (G8002A) was significantly higher among ß-TM patients than controls. The number of patients with cardiac disease, PH risk or nephropathy was significantly higher among AA genotype compared with GG and GA genotypes. Lactate dehydrogenase (LDH), serum ferritin, EMAP II, MDA, SOD and GPx were significantly higher in AA genotype. CONCLUSION: ET-1 gene polymorphism (G8002A) could be a possible genetic marker for prediction of increased susceptibility to cardiopulmonary and renal complications among pediatric patients with ß-TM.

Comparative study between chronic automated red blood cell exchange and manual exchange transfusion in patients with sickle cell disease: A single center experience from Saudi Arabia.

BACKGROUND: Red cell transfusion remains the gold standard in managing sickle cell disease (SCD) with severe complications. Offering red blood cell exchange (RBCX) either manual exchange transfusion (MET) or automated RBCX (aRBCX) can reduce the complications of chronic transfusion and maintain target Hb thresholds. This study audits the hospital experience of overseeing adult SCD patients treated with RBCX, both automated and manual, and compares the safety and efficacy. MATERIALS AND METHODS: This retrospective observational study was conducted as an audit for chronic RBCX for adult patients with SCD in 2015-2019 at King Saud University Medical City, Riyadh, Saudi Arabia. RESULTS: A total of 344 RBCX for 20 adult SCD patients who were enrolled in regular RBCX, (11/20) patients had regular aRBCX with a total of (157) sessions, and (9/20) patients had MET with a total of (187) sessions. The median level of HbS% post-aRBCX was significantly lower than MET (24.5.9% vs. 47.3%, P < 0.010). Patients on aRBCX had fewer sessions (5 vs. 7.5, P < 0.067) with better disease control. Although the median yearly pRBC units per patient for aRBCX was more than the double needed for MET (28.64 vs. 13.39, P < 0.010), the median ferritin level was 42 µg/L in aRBCX versus 983.7 µg/L in MET, P < 0.012. CONCLUSION: Compared to MET, aRBCX was more effective in reducing HbS, with fewer hospital visits and better disease control. Although more pRBCs were transfused, the ferritin level was better controlled in the aRBCX group without increasing alloimmunization risk.