Pyogenic bacterial infections of the CNS.

The etiology of pyogenic infections of the brain and meninges varies principally by age, predisposing causes or conditions, and anatomic site of the infection. An appreciation of these factors, plus the prudent use of noninvasive anatomic diagnostic techniques (such as CT) and examination of the CSF, will provide a basis for the empiric use of appropriate antibiotics. The beta-lactam antibiotics remain the preferred drugs whenever possible because of their broad spectrum on antimicrobial activity, efficacy in CNS infections, low cost, and low toxicity.