Cefoxitin resistance in community-acquired gram-negative bacillary bacteremia. Associated clinical risk factors.

Among 185 patients with nonneutropenic, community-acquired gram-negative bacillary bacteremias, clinical risk factors for cefoxitin resistance included any antibiotic taken within the last three weeks (25.6% cefoxitin resistance), long-term bladder catheterization or surgical urinary diversion (23.3%), hospitalization within the last 30 days (22.9%), and nursing home residence before admission (20.8%). Patients with none of these risk factors were less likely to have cefoxitin-resistant bacteremias (0.9%). When these risk factors were examined in the subgroups of urinary tract and non-urinary tract sources of community-acquired gram-negative bacillary bacteremia, they were also helpful in predicting sensitivity to trimethoprim-sulfamethoxazole and gentamicin. The presence of one or more of the risk factors identified may be a useful adjunct in determining initial empiric antimicrobial therapy for community-acquired gram-negative bacillary bacteremia.