2005 Volume 17 Issue 3 Pages 345-352
We conducted a bacteriological study of 209 patients with peritonsillar abscess treated in our in-patient department between October 1983 and March 2004. The patients were 160 males and 49 females ranging in age from 2 to 80 years (average age 33 years). Purulent effusions taken from the abscesses were cultured under aerobic and anaerobic conditions at the bacterial laboratory of Oita University Hospital. Bacteria were isolated in these cultures. Antibiotic susceptibilities were tested by a microdilution method. Antimicrobial resistance was defined according to the criteria of the National Committee for Clinical Laboratory Standards.
We detected 351 strains of bacteria in 187 (89%) of the 209 patients. About half of the patients showed mixed infection. Two hundred twenty-seven of the 351 strains were aerobic; the remainder were anaerobic. Aerobes were detected in about 70% of the patients, anaerobes were detected in 40% of the patients, and both types were detected in 20% of the patients. The aerobes most frequently identified were S. pyogenes (17.2%) and S. milleri group bacteria (17.2%), then non- S. milleri Oral streptococci bacteria (5.8%). Fifty-three percent of aerobes were β-hemolytic strep tococci. The anaerobes most frequently identified were Prevotella spp.(26.2%), Fusobacterium spp.(20.2%), Anaerobic gram- negative rod (19 .4%), and Peptostreptcoccus spp.(8.1%). About 40% of the S. pyogenes isolates were resistant to ofloxacin. About half of the S. milleri group isolates were resistant to cefotiam. Twenty-two percent of S. pyogenes, 20 % of Oral streptococci, and 9 % of anaerobes were clindamycin-resistant.
All patients in whom antimicrobial resistant pathogens were detected were treated successfully. However, when treating peritonsillar abscess, we should take into consideration the growing number of S. milleri group bacteria that are highly resistant to cephalosporin and the potential for the presence of clindamycin-resistant pathogens.