The objective was to demonstrate the aerobic and anaerobic microbiology of deep neck space
abscess and to analyze the coverage rate of different empiric
antimicrobial agents. A retrospective review of hospitalized patients with deep neck
abscess diagnosed at a tertiary-care, general hospital between April 2001 and October 2006. The study enrolled 100 patients. The bacterial cultures of 89 patients yielded positive results (89%). The predominant aerobes were viridans streptococci, Klebsiella pneumoniae, and Staphylococcus aureus. The predominant anaerobes included species of Prevotella, Peptostreptococcus, and Bacteroides. Five different combinations of empiric
antibiotics, namely regimen 1:
penicillin G and
clindamycin and
gentamicin, regimen 2:
ceftriaxone and
clindamycin, regimen 3:
ceftriaxone and
metronidazole, regimen 4:
cefuroxime and
clindamycin, and regimen 5:
penicillin and
metronidazole, were compared using the antimicrobial susceptibility of 89 cases. The coverage rates of regimens 1, 2, 3, 4, and 5 were 67.4%, 76.4%, 70.8%, 61.8%, and 16.9%, respectively. The coverage of regimen 5 was considerably worse than that of the other four regimens (p < 0.001). Regimen 2 was significantly better than regimen 4 (p < 0.001). Regimen 2 had better coverage than regimens 1 (p = 0.096) and 3 (p = 0.302), but the difference was not statistically significant. This study demonstrates the bacteriology of deep neck
abscess and analyzes the coverage rate of different empiric
antimicrobial agents. Regimens 1, 2, and 3 could be good candidates for empiric
antibiotics. Pathogen-directed antimicrobial
therapy should be adjusted after the culture results are obtained.