Hypersegmentation of neutrophils in the cerebrospinal fluid: Report of a case with hematologic correlation and review of the literature

Hypersegmented neutrophils can occasionally be seen in the cere‐brospinal fluid (CSF) of patients with acute pyogenic meningitis, and rarely as an artifact of cytocentrifugation. We report a case of florid neutrophil hypersegmentation in cytocentrifuged CSF specimens from a patient presenting with anemia and mental status changes. Megaloblastic anemia was excluded by a thorough hematologic evaluation, and the patient was later found to have an epidural abscess. The striking hypersegmentation is attributed to the combined effects of meningeal infection and cytocentrifugation, and a review of the available limited literature on cytomorphologic alterations in CSF cells, specifically neutrophils, is presented. Diagn Cytopathol 1994; 11:56–59. © 1994 Wiley‐Liss, Inc.