Bacteriology of acute and chronic sphenoid sinusitis

Aspirates of 16 acutely infected and 7 chronically infected sphenoid sinuses were processed for aerobic and anaerobic bacteria. A total of 29 isolates were recovered from the 16 cases of acute sphenoid sinusitis (1.8 per specimen): 22 aerobic and facultative (1.4 per specimen), and 7 anaerobic (0.4 per specimen). Aerobic and facultative organisms alone were recovered in 10 specimens (62%), anaerobes alone were isolated in 3 (19%), and mixed aerobic and anaerobic bacteria were recovered in 3 (19%). The predominant aerobic and facultative species were Staphylococcus aureus (9 isolates), Streptococcus spp (9), and Haemophilus influenzae (2). A total of 28 isolates were recovered from the 7 cases of chronic sphenoid sinusitis (4.0 per specimen): 11 aerobic and facultative (1.6 per specimen) and 17 anaerobic (2.4 per specimen). Aerobic and facultative organisms alone were recovered in I instance (14%), anaerobes alone in 3 instances (43%), and mixed aerobes and anaerobes in 3 instances (43%). The predominant aerobic bacteria were gram-negative bacilli (Klebsiella pneumoniae, Escherichia coli, and Pseudomonas aeruginosa; 1 each). The predominant anaerobes included Peptostreptococcus spp (4 isolates), Prevotella spp (5), and Fusobacterium spp (4). These findings illustrate the unique microbiology of acute and chronic sphenoid sinusitis.