Information on the epidemiologic, clinical, microbiologic and therapeutic aspects of community-acquired complicated intra-abdominal infections in paediatrics is limited. The objectives of this study were to investigate the epidemiologic, clinical, microbiologic and therapeutic characteristics of community-acquired complicated intra-abdominal infections occurring in children aged 1 month-15 y. Medical charts and microbiology data of all children hospitalized with complicated intra-abdominal infections were retrospectively examined. Complicated intra-abdominal infections were defined as infections extending beyond the viscus of origin into the peritoneal space, with subsequent development of abscess or peritonitis. One hundred and twenty-three patients with complicated intra-abdominal infections (99/123, 80% >5 y of age) were included; 113 (92%) had complicated acute appendicitis. Twelve (10%) patients underwent computerized tomography-guided percutaneous drainage of periappendicular abscesses. The mean rate of complicated intra-abdominal infections among patients with complicated acute appendicitis was 10% without significant changes during the study years. Positive intra-abdominal cultures were recorded in 97/108 (90%) evaluable patients; 65/97 (67%) cases were characterized by mixed bacterial flora growth. One hundred and ninety pathogens (aerobes n=164, 86%; anaerobes n=26, 14%) were isolated. Escherichia coli was the most common pathogen (94 isolates, 57%). In vitro amoxicillin/clavulanate coverage of E. coli and Klebsiella spp was modest (81% and 86%, respectively). The ampicillin/gentamicin/metronidazole regimen was more appropriate in vitro than the amoxicillin/clavulanate regimen (3/80, 4% resistant pathogens compared with 8/43, 19%; p=0.02). Post-operative complications were recorded in 33/123 (27%) patients. Time until defervescence to < 37.5 degrees C was shorter in children with periappendicular abscess than in children with generalized peritonitis (6+/-4 vs 4+/-3 days; p=0.009).
In conclusion: (1) most community-acquired complicated intra-abdominal infections occurred as a result of acute appendicitis; (2) the rate of complicated intra-abdominal infections among patients with acute appendicitis was low and without significant changes during the study period; (3) E. coli was the most frequently isolated pathogen; (4) amoxicillin/clavulanate provided only partial coverage for complicated intra-abdominal infection pathogens and should be used with caution in the empiric treatment of complicated intra-abdominal infections.