Shunt fluid aspiration: an adjunct in the diagnosis of cerebrospinal fluid shunt infection.

Bacterial isolates were obtained from 42 of 59 cultures of shunt fluid aspirated from patients with infected cerebrospinal fluid shunts. The etiologic agent was recovered from 24 to 25 aspirates from patients who were not receiving antibiotics and from 18 of 34 aspirates from patients who were receiving antibiotics. Aspiration, culture, and Gram stain of shunt fluid should be considered in patients suspected of having a shunt infection.