Walsh & Hoyt: Intracranial Infections-Empyema

Intracranial abscesses and empyemas caused by H. influenzae are uncommon but occur in bothch ildren and adults (20,38,43,49,1855,1856). In many cases, they are part of a polymicrobial infection and result from spread of organisms from the inner ear or paranasal sinuses. Indeed, in one study of 17 patients withintracranial subdural empyemas, the presence of H. influenzae as a single isolate was 100% sensitive and 40% specific for an otogenic cause of the empyema (1856). Nevertheless, the overall rarity of Haemophilus as a cause of intracranial abscesses is emphasized by a series of 123 cases of brain abscess in which the organism was not found in a single case (47).