Bacteriolytic activity of normal and pathological cerebrospinal fluid.

The bacteriolytic activity of 153 samples of cerebrospinal fluid (CSF) from patients with various diseases was measured by determining the ability of the CSF to cause lysis of a suspension of killed cells of Micrococcus lysodeikticus. Normal CSF did not show significant bacteriolytic activity. A high activity was found in patients with bacterial meningitis (mainly meningococcal), only to some extent correlated with the protein and cell content of the CSF. Slight elevation of protein and cell content of CSF in patients with diseases other than bacterial meningitis was not accompanied by significant bacteriolytic activity. The CSF from a patient with lymfosarcoma, with as much as 2300 cells/mm3, thus was negative. Also the CSF from patients with serous (viral) meningitis was usually negative. Measurement of bacteriolytic activity in CSF may be of diagnostic importance in cases presenting slight elevation of cell number and protein. Further studies of the significance of the bacteriolytic response in meningitis caused by different microorganisms are warranted.