Cerebrospinal fluid pleocytosis in children with pneumonia but lacking evidence of meningitis.

Headache, nuchal rigidity, positive Kernig's sign, and even convulsions may be observed during severe bacterial infections such as pneumonia, pyelonephritis, typhoid fever, and bacillary dysentery. In such cases, meningitis can be excluded only by documentation of normal cerebrospinal fluid (CSF). The authors describe four children with lobar pneumonia in whom the clinical signs of meningeal irritation were associated with a mild increase in the white blood cell count in the CSF (pleocytosis) although there was no other evidence of meningeal infection.