Cerebral ventriculitis in the hydrocephalic mouse: a histological and scanning electron microscope study.

Staphylococci are the commonest organisms found in infected cerebrospinal fluid shunts in hydrocephalic patients. In the present study, staphylococcus albus was injected (1200-500,000 organisms in 10 microliters saline) into the ventricles of the hydrocephalic mouse SUMS - hy - 3/+ (temporary strain name). The bacteria appeared to have little direct effect upon the ependymal cells lining the ventricles and were not found as free organisms in the subependymal tissue. Staphylococci were phagocytosed by polymorphonuclear leukocytes which entered the ventricle from the choroid plexus and through the ependyma from subependymal vessels. Macrophages on the lining of the hydrocephalic ventricles also played a significant role in the phagocytosis of bacteria in the early stages of infection.