Otogenic Cranial Base Osteomyelitis

Abstract

To review the presentation, microbiology, and long-term results of treating otogenic cranial base osteomyelitis to develop a prognosis-based disease classification system. Thirty-eight patients with otogenic cranial base osteomyelitis treated between 1989 and 2002 were studied. Patient demographics, presentation, pathogens, details of therapy, and disease-specific survival were recorded. Patients were stratified using Technetium-99 single-photon emission computerized tomography (SPECT) at presentation into 4 grades: I, mild uptake; II, focal mastoid/temporal bone uptake not reaching midline; III, petrous temporal bone uptake reaching midline; and IV, uptake crossing midline, involving the contralateral temporal bone. Actuarial analysis was used to identify prognostic factors. There were 27 men. The average age at presentation was 65 +/- 16 years (range, 19-95 yr). The median age-adjusted Charlson comorbidity score was 5, and 63% of patients were diabetic. The most common presenting symptoms were pain and otorrhea, and 8 patients had cranial nerve neuropathy. Pseudomonas aeruginosa was the most common bacterial pathogen (n = 28; 74%), and 9 patients had fungal or mixed infections. On average, antibiotics were administered for 161 days, and 6 patients had concomitant surgery. The average follow-up was 33 months, and 3-year disease-specific survival was 76%. Univariate predictors of survival were the SPECT grade, fungal/mixed infections, Charlson score, immune compromise, and cranial nerve neuropathy. The only independent predictor of survival on multivariate Cox regression was the SPECT stage at presentation. Cranial base osteomyelitis is associated with significant morbidity and mortality and requires prolonged treatment. Long-term outcome can be predicted from the initial SPECT scan.