PREVALENCE OF ANTIMICROBIAL-RESISTANT PATHOGENS IN MIDDLE-EAR FLUID -MULTINATIONAL STUDY OF 917 CHILDREN WITH ACUTE OTITIS-MEDIA

The management of acute otitis media is complicated by the emergence o f resistance to p-lactam and other antibiotics among common pathogens. We conducted a large, international study of infants and children wit h acute otitis media to identify pathogens and susceptibility patterns , During the winter of 1994 to 1995, middle ear fluid samples were col lected from 917 patients with acute otitis media in Bulgaria, the Czec h Republic, Hungary, Romania, Slovakia, Israel, and the United States, A single reference laboratory performed in vitro susceptibility testi ng. Pathogens were isolated from 62% of the patients. For Streptococcu s pneumoniae (30% of the patients), untypeable Haemophilus influenzae (17%), and Moraxella catarrhalis (4%), there was significant variation among geographic regions (P < 0.001), The composite susceptibilities of these three organisms to amoxicillin ranged from 62% in the United States to 89% in Eastern and Central Europe; the corresponding suscept ibilities to amoxicillin-clavulanate ranged from 90% in Israel to 95% in Eastern and Central Europe, beta-Lactamase was produced by 31 and 1 00% of the isolates of H. influenzae and M. catarrhalis, respectively, More isolates of S. pneumoniae were susceptible to amoxicillin (90%) or amoxicillin-clavulanate (90%) than to penicillin (70%; P = 0.002). The prevalence of resistant S. pneumoniae was highest in patients less than 12 months of age, S. pneumoniae, H. influenzae, and M. catarrhal is remain the most important bacterial pathogens in patients with acut e otitis media; however, their prevalence is variable and resistance p atterns are changing.