[mass noun] The presence of an abnormally large number of lymphocytes in the cerebrospinal fluid.
- ‘Examination of the cerebrospinal fluid typically shows a moderate lymphocytic pleocytosis, though sometimes there may be no cells or neutrophils may predominate.’
- ‘The diagnosis of meningitis was based on a typical clinical presentation and a marked neutrophilic pleocytosis in the cerebrospinal fluid.’
- ‘The cerebrospinal fluid shows increased protein content and pleocytosis with normal glucose concentration, but the virus is more commonly isolated from the nasopharynx or stools.’
- ‘If pleocytosis was present, the CSF should be re-examined every six months until the white blood cell count is normal.’
- ‘These patients often have a peripheral eosinophilic pleocytosis.’