This report highlights the case of a 79-year-old man with new onset seizures who developed loss of consciousness. CSF analysis showed the presence of both cryptococcus antigen and anti-NR1 antibodies, suggesting the possibility of cryptococcus meningitis vs. anti-NMDA encephalitis.

The patient is a 79-year-old male with a past medical history of diabetes, hypertension, and A-fib who presented with generalized status epilepticus. His family reported subacute onset functional and cognitive decline that started a few months before this presentation. He continued to decline, to the point where he was unable to do his ADLs, as well as having some fine tremors in upper extremities intermittently. Prior to the hospitalization, the patient had multiple witnessed generalized seizure activity. He underwent imaging at an outside facility which was reportedly unremarkable and was intubated and sedated prior to arrival at our hospital.

The patient was weaned off sedation but remained obtunded for several days while on mechanical ventilation. cEEG during admission showed diffuse encephalopathy and highly epileptogenic focus in the right posterior head. Labs showed the presence of cryptococcus antigen in the CSF. He was given IV amphotericin and IV flucytosine for a total of 14 days during the admission for cryptococcus meningitis induction therapy. His mental status recovery was poor despite this treatment, and he was arousable but mostly somnolent on discharge. Paraneoplastic autoantibody evaluation was later positive for anti-NR1 antibodies, although immunotherapy was not initiated given lack of clearance from infectious disease. 5 months later, he was rehospitalized due to severe cognitive impairment and poor neurological recovery despite maintenance treatment for cryptococcus meningitis.

This case demonstrates a possible coexistence of cryptococcus meningitis and anti NMDA encephalitis. Anti-NR1 antibodies could also be secondary to CNS infection, and it raises the question whether cryptococcus infection can induce development of anti-NMDA receptor antibodies.