Salmonella Group D1 Subdural Empyema Mimicking Subdural Hematoma: A Case Report

Subdural empyema is caused by various pathogens. The most typical clinical presentation may include fever, headache, seizures, and altered consciousness. However, Salmonella infections are relatively rare. Representative features of Salmonella infection include fever and gastrointestinal symptoms such as diarrhea, vomiting, and abdominal cramping pain. Extra-gastrointestinal invasion of Salmonella in the central nervous system is unusual. We present the case of an afebrile 58-year-old male who presented with a headache and a progressive dull response for a week. He had a closed head injury approximately 1 week before this visit. A tentative diagnosis led to a subdural hematoma (SDH), and he underwent urgent burr hole surgery. Intraoperative findings showed a large amount of brown-yellow pus in the subdural space instead of the pathognomonic bloody serosanguinous or thick motor oil, which is typical of SDH. The intraoperative culture yielded Salmonella group D1. After initial brain surgery and 52 days of effective intravenous administration of a third-generation cephalosporin (Ceftriaxone 2000 mg per day), the patient recovered fully without neurological deficits. His consciousness and mentality remained normal without focal weakness of the limbs for over 5 years of follow-up. This is a unique case with an atypical initial presentation that leads to a final unexpected diagnosis. Ongoing treatment strategies include a combination of surgical drainage for disease confirmation and appropriate medical antibiotics.