Clinical and therapeutic features of nonpostoperative nosocomial intra-abdominal infections

To compare the clinical, microbiological, and therapeutic features of nonpostoperative nosocomial intra-abdominal infections (non-PostopNAI) with community-acquired intra-abdominal infections (CAI).

Prospective (June 2000 through January 2001) consecutive case series analysis of patients operated for secondary nonpostoperative intra-abdominal infections collected in 176 study centers (surgical wards and intensive care units).

Clinical, microbiological, and therapeutic characteristics of CAI and non-PostopNAI infections were collected. Management of antibiotic therapy was decided by the attending physician. The efficacy of treatment was evaluated over a 30-day period after the index episode.

Evaluatable observations (n = 1008) were collected (761 CAI and 247 non-PostopNAI), including 285 intensive care unit patients. When compared with CAI patients, non-PostopNAI patients presented an increased interval between admission to the surgical ward and operation (1.3 +/- 1.5 vs. 0.5 +/- 0.7 days in CAI patients; P < 0.001), increased proportions of underlying diseases, a more severe clinical condition as assessed by increased proportions of hospitalization in the intensive care unit (48% vs. 22% in CAI patients, P < 0.001) and a higher SAPS II score (34 +/- 15 vs. 24 +/- 14, P < 0.001). In non-PostopNAI patients, increased proportions of therapeutic failure (15% vs. 7% in CAI patients, P < 0.01) and of fatalities (12% vs. 4% in CAI patients, P < 0.001) were observed.

Delayed diagnosis and increased severity are the main characteristics of non-PostopNAI infections. Microbiological features are quite similar in CAI and non-PostopNAI infections, suggesting that antibiotic therapy recommended for CAI infections could be applied to non-PostopNAI patients. Characteristics of non-PostopNAI patients should lead to identify them as a specific entity in clinical trials.