[Community-associated methicillin-resistant Staphylococcus aureus sepsis presenting with encephalopathy-like symptoms in a previously healthy young adult].

A 32-year-old previously healthy man developed abnormal behavior two days after the onset of fever. He had experienced epistaxis during consecutive work days prior to the onset. While clinical findings suggested encephalitis, blood cultures yielded methicillin-resistant Staphylococcus aureus (MRSA). No obvious local infectious foci were identified in the skin or soft tissues; however, brain MRI revealed multiple embolic-like lesions. The MRSA strain produced markedly elevated toxic shock syndrome toxin-1 (TSST-1), suggesting a toxic shock syndrome-like state. Although initial empirical therapy did not cover MRSA, targeted anti-MRSA agents were started following its identification. Assuming an occult infectious focus, intravenous anti-MRSA therapy was continued for 6 weeks after blood cultures converted to negative. He was discharged on hospital day 54 without neurological sequelae. Community-associated MRSA can cause severe sepsis even in young individuals, and encephalopathy may be the initial presentation. Clinicians should consider MRSA sepsis in the differential diagnosis of patients presenting with encephalitis-like symptoms. In this case, the preceding epistaxis suggested that nasal colonization served as the portal of entry.