Renal functions in pediatric patients with beta-thalassemia major: role of renal color doppler

ABSTRACT

This work aimed to evaluate renal status in pediatric patients with beta-thalassemia by laboratory investigations and color Doppler sonography. The study included thirty-five children with beta-thalassemia major [age range 6-16 years] and 12 healthy children had laboratory investigation as well as renal color Doppler studies. The renal function was evaluated by studies of urine osmolality, urinary protein [Up], creatinine clearance [Ccr], fractional excretion of sodium [FENa], potassium [FEK] and uric acid [FEUA] and malondialdehyde [UMDA]. Blood samples were collected for complete blood count, blood urea nitrogen [BUN], serum creatinine [Scr], electrolytes, ferritin and alkaline phosphatase just before transfusion. Urine volume, high urinary protein to creatinine [Up/cr] and urinary malondialdehyde to creatinine [UMDA/cr] were investigated in the two groups. Color Doppler sonography was done to the thalassemic as well as the control groups. Assessment of the resistive index [RI] values of segmental vessels of the kidney was done. The results obtained confirmed the high frequency of renal abnormalities in beta-thalassemia patients and indicated some degree of proximal tubular dysfunction. This suggested that the damage might be caused by anemia and increased oxidation induced by excess iron deposits. The increase of serum K, P and uric acid in thalassemic children were attributed to the rapid erythrocyte turnover. The findings of high Up/cr and UMDA/cr ratio denotes proximal renal tubular damage secondary to oxidative lipid peroxidant mediated by iron overload. The elevated RI of renal arteries is an indication of active disease in tubulo-interstitial renal compartment. The study also proved that the use of renal color Doppler is helpful in early detection of renal affection in thalassemic patients, even in the absence of gray scale abnormalities