[Actinomyces viscosus in subdural empyema].

The authors describe the finding of Actinomyces viscosus in pus from a subdural empyema in a child patient. When searching for the probable primary source of this uncommon infection of the central nervous system the authors identified by cultivation the same bacterial strain in a periapical dental granuloma. Bacterial diagnosis and radical surgical and antimicrobial therapy led to normalization of a clinical condition with an initially unfavourable prognosis.