NDM-Producing Escherichia coli subdural empyema mimicking chronic subdural hematoma: a case report

The case involves an 82-year-old man who presented with fever and progressive neurological deterioration. Head computed tomography repeatedly interpreted a left frontotemporoparietal subdural collection as chronic subdural hematoma. Blood culture and metagenomic sequencing analyses revealed multidrug-resistant Escherichia coli carrying the NDM gene and other resistance determinants. Despite antimicrobial therapy and clearance of bacteria from blood cultures, fever, impaired consciousness, and enlargement of the subdural lesion persisted. Surgical exploration via burr-hole revealed purulent material instead of hematoma, confirming the diagnosis of subdural empyema. Culture of the obtained pus also confirmed multidrug-resistant E. coli with blaNDM, blaCTX-M, and mcr-1 genes. At the latest follow-up, the patient was stable with a Glasgow Coma Scale score of 15. The case emphasizes that negative blood cultures do not exclude persistent compartmentalized intracranial infection.