Intracranial subdural abscess with polymicrobial infections due to frontal sinusitis in an adolescent: life-threatening complication of a common disease.

Intracranial abscess is one of the most serious complications of frontal sinusitis, particularly among adolescents, even in the absence of odontogenic infection. Polymicrobial infections due to anaerobes are common. Because antibiotic therapy alone is usually ineffective, early endoscopic sinus surgery is the key for infection control and good clinical outcomes.