Microbiology of acute and chronic maxillary sinusitis associated with an odontogenic origin

Objectives. To study the microbiology of sinusitisassociated with odontogenic origin. Methods. Aspirates of 20 acutely and 28 chronically infected maxillary sinuses that were associated with odontogenic infection were processed for aerobic and anaerobic bacteria. Results. A total of 66 isolates were recovered from the 20 cases of acute sinusitis (3.3/specimen), 16 aerobic and facultatives, and 50 anaerobic. Aerobes alone were recovered in 2 (10%) specimens, anaerobes only in 10 (50%), and mixed aerobic and anaerobic bacteria in 8 (40%). The predominant aerobic were a-hemolytic streptococci (5), microaerophilic streptococci (4), and Staphylococcus aureus (2). The predominant anaerobes were anaerobic Gram-negative bacilli (22), Peptostreptococcus (12), and Fusobacterium spp. (9). A total of 98 isolates were recovered from the 28 cases of chronic sinusitis (3.5/patient): 21 aerobic and facultatives and 77 anaerobic. Aerobes were recovered in 3 (11%) instances, anaerobes only in 11 (39%), and mixed aerobic and anaerobic bacteria in 14 (50%). The predominant aerobes were a-hemolytic streptococci (7), microaerophilic streptococci (4), and S. aureus (5). The predominant anaerobes were Gram-negative bacilli (41), Peptostreptococcus (16), and Fusobacterium spp. (12). Thirteen beta-lactamase-producing bacteria (BLPB) were recovered from 10 (50%) patients with acute sinusitis and 25 BLPB from 21 (75%) patients with chronic sinusitis. No correlation was found between the predisposing odontogenic conditions and the microbiological findings. Conclusions: These data illustrate the similar microbiology of acute and chronic maxillary sinusitis associated with odontogenic infection where anaerobic bacteria predominate in both types of infections.