The diagnostic significance of serum ferritin indices in patients with malignant and reactive histiocytosis.

Iron metabolism was studied in 10 patients with malignant histiocytosis (MH), in 16 patients with histiocytosis-X (Langerhans cell histiocytosis) and in 34 patients with reactive proliferation of the mononuclear phagocytes (MPS). Eight MH patients had a considerably increased level of serum ferritin (SF). The average level of SF was 6070 +/- 957 mg/l for MH patients, which is significantly greater than the SF level for HX and RH patients. The study of the serum ferritin profiles suggests that the main pathogenetic mechanism of hyperferritinaemia in MH is the synthesis and secretion of ferritin by neoplastic mononuclear phagocytes. From this, hyperferritinaemia in MH may be considered as pathognomic of this disease and used as an additional diagnostic criterion. In addition, SF is the most informative parameter for the clinical practice among the indices of the functional state of MPS.