Anaerobic mastoiditis: a report of two cases with complications.

Aerobic bacteria are responsible for most cases of suppurative otitis media/mastoiditis (OM/M). As many as 20-30% of middle ear aspirates in acute otitis media, however, are reported to be sterile on aerobic culture. Some of these cases may be due to anaerobic bacteria. Two cases of OM/M due to anaerobic bacteria are reported. The first patient had no antecedent ear disease and developed a large Bezold abscess caused by Fusobacterium varium. The second patient had attic retraction pouches bilaterally and a history of otorrhea. This patient developed labyrinthitis and meningitis due to B. fragilis. The clinical progression of disease in both cases indicates that anaerobic OM/M can follow a deceptively asymptomatic course. By contrast, complications of OM/M occur abruptly and extend rapidly in a manner typical of acute aerobic disease. Both cases required surgery for cure.