Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content + Download Section PDF Listen ++ For further information, see CMDT Part 33-31: Anaerobic Infections + Key Features Download Section PDF Listen +++ ++ Common cause of brain abscess, subdural empyema, or septic CNS thrombophlebitis The organisms reach CNS by direct extension from sinusitis, otitis, or mastoiditis or by hematogenous spread from chronic lung infections + Clinical Findings Download Section PDF Listen +++ ++ Various neurologic deficits + Diagnosis Download Section PDF Listen +++ ++ MRI scan (most sensitive) or CT scan Culture of infected tissue + Treatment Download Section PDF Listen +++ ++ Antimicrobial therapy is an important adjunct to surgical drainage Ceftriaxone, 2 g every 12 hours intravenously, plus metronidazole, 500 mg every 8 hours intravenously Duration of antibiotic therapy is 6–8 weeks but should be based on follow-up imaging Some small multiple brain abscesses can be treated with antibiotics alone without surgical drainage