Prevalence, causes and effects of increased iron storage in patients with kidney transplantation

Patients on chronic hemodialysis often need blood transfusions due to erythropoietin deficiency. Even after successful kidney transplantation iron overload may persist. Former histological studies have revealed siderosis of the liver in 69% of all patients whose serum ferritin was above 1100 ng/ml. The aim of the present study was to evaluate the influence of iron overload on liver function. In 146 symptom free patients with renal allografts serum ferritin was determined to detect possible iron overload. Serum ferritin between 4 and 5480 ng/ml were found (women: 358.7 +/- 105.3; men 282.4 +/- 63.3 ng/ml; x +/- SEM). Twelve patients (8.1%) had ferritin levels higher than 1100 ng/ml. These twelve patients as well as another group of eight patients with renal allografts whose serum ferritin was known to be higher than 1100 ng/ml were included for further evaluation. Their data were matched and compared with those of a control group also patients with renal allograft (same age and sex) whose serum ferritin was lower than 1100 ng/ml. Transaminases (SGPT 22.6 +/- 3.6 vs. 15.4 +/- 6.0 U/l; SGOT 14.7 +/- 2.0 vs. 13.0 +/- 4.8 U/l) and plasma glucose (90.5 +/- 7.1 vs. 76.8 +/- 3.7 mg/dl) were found to be significantly higher (p less than 0.05) in patients with serum ferritin levels above 1100 ng/ml. Elevated transaminases were significantly more frequent in patients with high serum ferritin (9 vs. 2; p less than 0.02) as compared with the control. Ferritin levels significantly correlated with the number of preceding blood transfusions (p less than 0.002). Hbs-persistence was detected in six out of 20 patients with high ferritin levels but only in one out of 20 in the control group (p less than 0.05) whereas anti-Hbs prevalence was not different in the two groups. These data indicate that chronic iron overload should be considered as a possible cause of chronic liver disease in patients with renal allografts.