Brain abscess in immunocompetent patient?,”Headaches, focal neurologic deficit, and ring-enhancing intracranial lesions on contrast CT scan of the brain in immunocompetent patients with an adjacent bacterial infection (eg
sinusitis) are most likely due to a brain abscess. Fever is present only in 50% of cases. Viridians streptococci and other head-and-neck anaerobes are the most common pathogens when brain abscess results from sinusitis.”