Antibiotic-resistant bacteria in pediatric chronic sinusitis

Background. Limited information exists on emerging bacterial resistance pat terns in pediatric chronic sinusitis. Methods. A retrospective review (1995 to 1998) of the aerobic microbiology of chronic sinusitis in children at a tertiary care children's hospital was conducted. One hundred nineteen children (mean age, 4.9 years) with maxill ary sinusitis of >8 weeks duration and no known immunodeficiency or cystic fibrosis who underwent antral irrigation were included. Results. One hundred sixty-one of 240 (67%) aerobic cultures were positive, yielding 274 isolates, Eighty-eight positive cultures were polymicrobial. The most frequent isolates were non-typable Haemophilus influenzae (24%), S treptococcus pneumoniae (19%), Moraxella catarrhalis (17%), coagulase-negat ive Staphylococcus (6%), alpha-streptococci (6%), diphtheroids (5%), Staphy lococcus aureus (3%) and Neisseria spp, (3%). Rates of nonsusceptibility of Streptococcus pneumoniae were 64% for penicillin (24% high grade resistanc e), 40% for cefotaxime, 18% for clindamycin and 0% for vancomycin. Rates of nonsusceptibility of S. pneumoniae did not change significantly during the study period. Thirty-nine percent of H. influenzae isolates were beta-lact amase-positive and 44% were non-susceptible to ampicillin (41% high grade r esistance). Beta-lactamase positivity of H. influenzae decreased during the study period (P = 0.06). All M. catarrhalis isolates tested were beta-lact amase-positive. Conclusion. This study indicates that the aerobic pathogens in pediatric ch ronic sinusitis include bacteria typical of acute sinusitis as well as orga nisms more characteristic of chronic disease. Moreover it highlights the si gnificant role of antibiotic-resistant aerobes, including multiply resistan t S. pneumoniae, in pediatric chronic sinusitis.