SERUM FERRITIN AND TISSUE IRON IN ANEMIC DIALYSIS PATIENTS

The relationship between serum ferritin and tissue iron was investigat ed in 26 dialysis patients (17 hemodialysis patients, 9 chronic perito neal dialysis patients) with anemia (median hemoglobin 74 g/l, range 5 6-92 g/l). Serum ferritin ranged from 18 to 9,435 mu g/l (median 450 m u g/l). Tissue iron was assessed in the liver biopsies of 4 hemodialys is patients with iron overload (serum ferritin 1,150-9,435 mu g/l), in the muscle biopsies of 5 patients with serum ferritin 170-9,435 mu g/ l, and in bone marrow aspirations (semiquantitative assessment). The m ean liver iron concentration was 15.4+/-8.0 mu g Fe/mg protein (mean /- SD), which is similar to that previously found in patients with unt reated idiopathic hemochromatosis. Four patients with serum ferritin 1 70-620 mu g/l had muscle iron concentrations (0.33 +/- 0.10 mu g Fe/mg protein) similar to those found in controls (0.23 +/- 0.10, means +/- SD). One patient with serum ferritin 9,435 mu g/l had a markedly incr eased muscle iron concentration (1.3 mu g Fe/mg protein). The bone mar row iron was assessed as negative in 3 patients (serum ferritin 44-85 mu g/l), positive in 8 (serum ferritin 18-379 mu g/l), increased in 11 patients (serum ferritin 222-4,210 mu g/l). and was markedly increase d in 2 patients (serum ferritin 4,550 and 9,435 mu g/l). Bone marrow i ron correlated significantly with serum ferritin concentrations (spear man rank correlation coefficient rho = 0.89, p < 0.001). These results show that in dialysis patients with a stable iron balance and unstimu lated erythropoiesis, i.e., patients without erythropoietin treatment and parenteral iron, serum ferritin is a useful indicator of iron stor es. Our findings also suggest that the relationship between tissue iro n and serum ferritin levels in end-stage renal disease is altered, i.e ., a relative increase in serum ferritin levels unrelated to iron stor es is observed in dialysis patients.