Aerobic and anaerobic microbiology of suppurative sialadenitis

Aspirates of pus from acute suppurative sialadenitis were investigated for the presence of aerobic and anaerobic bacteria. A total of 47 specimens, 32 from parotid, 9 from submandibular and 6 from sublingual glands yielded bacterial growth. Fifty five isolates, 25 aerobic and 30 anaerobic, were isolated from parotid infection: anaerobic bacteria only were detected in 13 (41%) specimens, aerobic or facultative bacteria only in 11 (34%) and mixed aerobic and anaerobic bacteria in 8 (25%). Of a total of 17 isolates, 8 aerobic and 9 anaerobic, from submandibular gland infection: anaerobic bacteria only were detected in 3 (33%) specimens, aerobic or facultative bacteria only in 4 (44%) and mixed aerobic and anaerobic bacteria in 2 (22%). Ten isolates, 5 aerobic and 5 anaerobic, were from sublingual gland infection: anaerobic bacteria only were detected in 2 (33%) specimens, aerobic or facultative bacteria only in 2 (33%) and mixed aerobic and anaerobic bacteria in 2 (33%). The predominant aerobes were Staphylococcus aureus and Haemophilus influenzae while the predominant anaerobes were gram-negative bacilli (including pigmented Prevotella and Porphyromonas spp., and Fusobacterium spp.) and Peptostreptococcus spp. The study highlights the polymicrobial nature and importance of anaerobic bacteria in acute suppurative sialadenitis.