Impaired metabolic activity of phagocytosing neutrophils in agnogenic osteomyelofibrosis with splenomegaly: a longitudinal study.

Functional and enzyme activity of neutrophils in patients with agnogenic osteomyelofibrosis (AOM) is still a subject of controversy, probably owing to the heterogeneity of the abnormalities observed from patient to patient, and the absence of longitudinal studies performed during the course of the disease. For a better definition of these abnormalities, 40 patients with untreated AOM were studied from the time of diagnosis, and in 12 cases, neutrophil function and enzyme activity were reassessed at one-year intervals for 3-5 years. The results showed that all abnormalities were serum-independent. Mean ingestion rate in neutrophils from patients were similar to that of the controls but individual values were more varied, with some very high and some low ingestion rates. Histochemical latex ingestion and nitroblue tetrazolium reduction were lower in patients than in controls, as were cyanide-insensitive O2 consumption and superoxide anion and H2O2 production. Mean iodination was also decreased and, in most patients, was related to a decrease in H2O2 production. However, in eight patients H2O2 production was normal, although an iodination deficiency was found. Myeloperoxidase activity was low in five of these cases. In the other three patients this discrepancy was not explained. The longitudinal study of 12 patients showed that defects observed in the early stages of the disease remained or were aggravated, and that new abnormalities appeared during the course of the disease.