Cytological investigation of CSF in leptospiral cerebral arteritis

Summary Cytological investigation of CSF from 32 cases with leptospiral cerebral arteritis (LCA) was done with optical microscope, among which 6 were examined with SEM simultaneously. The results indicated that the cytological alterations in CSF of these patients were mainly due to a complicated reaction, in which lymphoid cell reaction was predominant. Using SEM, several types of cells with special surface architecture were demonstrated, such as bleb-like cells, uropod-like cells, bleb-uropod-like cells and hybrid-type monocytes. A special type of cells not reported previously was discovered and called crown-like cells by the authors. It is suggested that proliferation of immune competent cells exists in CSF. On the other hand, inflammatory cell reactions were also prominent in CSF, coincidently occurring with increase of immunoglobulin level in CSF in more than half of the patients. Considering the cytological and immunological changes in CSF and the features of the pathological lesion of the arteries involved together,we suggest that the pathogenesis of LCA is correlated with allergy and/or inflammation in CSF after leptospiral infection.