Histochemical studies of lysosomal enzyme and nitroblue tetrazolium reduction of phagocytes in the cerebrospinal fluid of patients with infectious diseases of the central nervous system.

Abstract

Lysosomal enzyme levels and nitroblue tetrazolium (NBT) reduction of phagocytes in the cerebrospinal fluid (CSF) of patients with infectious diseases of the central nervous system (CNS) were studied histochemically to evaluate the function of phagocytes. Lysosomal enzymes of acid phosphatase and beta-galactosidase were demonstrated in mononuclear phagocytes and leptomeningeal cells, but not in polymorphonuclear leukocytes (PMN) and lymphocytes. In tuberculous meningitis, more than 60% of the cells were positive for the enzymes as compared with less than 30% for other diseases. Besides, the cells which stained highly for the enzymes were often found in the CSF of tuberculous meningitis. The lysosomal enzyme levels in the cells were dependent on the nature of the infection rather than on the intensity of inflammation when judged by total cell count in the CSF. On the other hand, reduced NBT formazan was found in PMN, mononuclear phagocytes, and leptomeningeal cells. The intensity of NBT reduction by these cells correlated well with the total cell count in CSF; i.e., enhanced NBT reduction by phagocytes reflected the intensity of the inflammation in the subarachnoid space. Thus, histochemical study of phagocytes in CSF can provide useful additional aids to the diagnosis of the nature and stage of CNS infection.