Deep neck abscess: an analysis of microbial etiology and the effectiveness of antibiotics

Shih-Wei Yang^1,2, Ming-Hsun Lee^3,4, Lai-Chu See⁵, Shu-Huan Huang⁶, Tsung-Ming Chen⁷, Tai-An Chen^1,4

¹Department of Otolaryngology-Head and Neck Surgery, Chang Gung Memorial Hospital, Keelung; ²Graduate Institute of Clinical Medical Sciences, Chang Gung University, Taoyuan; ³Division of Infectious Diseases, Department of Internal Medicine, Chang Gung Memorial Hospital, Linkou; ⁴School of Medicine, Chang Gung University, Taoyuan; ⁵Biostatistics Consulting Center, Department of Public Health, Chang Gung University, Taoyuan; ⁶Department of Pathology, Chang Gung Memorial Hospital, Keelung; ⁷Department of Otolaryngology-Head and Neck Surgery, Koo Foundation Sun Yet-Sen Cancer Center, Taipei, Taiwan

Abstract: 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.

Keywords: deep neck abscess, microbiology, antibiotics, empiric