Multiloculated pyogenic brain abscess: experience in 25 patients

To report our experience in treating multiloculated pyogenic brain abscess and determine whether there are differences in the bacteriology, predisposing factors, treatment choices, and outcomes between multiloculated and uniloculated brain abscesses.

We studied clinical data collected during a 16-year period from 124 patients with pyogenic brain abscess, including 25 cases of multiloculated abscess.

The incidence of multiloculated brain abscess was 20%. In these 25 patients, hematogenous spread from a remote infectious focus was the most common cause of infection, as it was for the cases of uniloculated abscess. Headache and hemiparesis were the most common symptoms in patients with multiloculated abscess. In patients with uniloculated abscess, fever was the most common symptom. Viridans streptococci were the most commonly isolated pathogens. Bacteroides fragilis was the most common anaerobe in multiloculated abscess, and aerobic gram-negative bacilli were the most common pathogens in patients with uniloculated abscess. Of the patients with multiloculated abscess, 21 were treated surgically and 4 were treated with antibiotics only. Overall, eight patients (38%) needed another operation because of abscess recurrence after the initial operation. In uniloculated abscess, the rate of abscess recurrence after initial surgery was 13.1%. Mortality was 16% in multiloculated abscess and 17.1% in uniloculated abscess.

Multiloculated abscesses accounted for 20% of our patients with pyogenic brain abscess. Excision seems to be the more appropriate surgical choice in multiloculated abscess. Prognosis for patients with multiloculated abscess can be as good as that for patients with uniloculated abscess. However, clinicians must carefully monitor these patients because the possibility of recurrence after surgery is significantly higher in patients with multiloculated abscess than in those with uniloculated abscess.