Brain Abscess Arising From Pansinusitis in an Immunocompetent Young Adult: A Diagnostic Challenge.

Brain abscesses are rare but potentially life-threatening infections that require prompt recognition and treatment. Although they typically occur in patients with identifiable risk factors, they can occasionally present in otherwise healthy individuals. Sinusitis is a recognized source of intracranial infection, but its progression to a brain abscess in immunocompetent patients is uncommon and may be clinically subtle. We report the case of a 21-year-old previously healthy male who presented to the emergency department (ED) with a non-specific bifrontal headache. He was initially diagnosed with migraine and discharged. Eight days later, he returned with worsening symptoms, including photophobia and fatigue. Imaging revealed a mucocele involving multiple paranasal sinuses and a right frontal lobe brain abscess with associated meningitis. Cultures from surgical drainage grew Streptococcus anginosus and Staphylococcus aureus. The patient underwent surgical abscess drainage and sinus surgery, followed by intravenous antibiotics, with complete recovery. This case highlights the importance of maintaining a high index of suspicion for intracranial complications of sinusitis, even in immunocompetent patients with non-specific symptoms. Timely neuroimaging and multidisciplinary management are essential for favorable outcomes in such presentations.