Herpes Encephalitis with Subsequent Right MCA Stroke, Subarachnoid Hemorrhage, and NMDA-R Encephalitis - A 22-year-old’s Complex Rehabilitation Journey: A Case Report.

Case Diagnosis: 22-year-old male with Herpes simplex meningoencephalitis (HSE) with subsequent right middle cerebral artery stroke (MCA), subarachnoid hemorrhage (SAH), and NMDA receptor encephalitis (NMDAR).

Case Description or Program Description: The patient presented multiple times to the emergency department with persistent headaches and vomiting, but was discharged each occasion due to unremarkable imaging. He developed weakness, fever, and altered mental status, prompting acute admission. CT head revealed SAH and vasogenic edema in the bifrontal and right temporal lobes. Subsequent MRI brain confirmed a right MCA infarct. CSF analysis and PCR identified HSE as the etiology. Upon transfer to acute rehabilitation, initial exam was significant for cognitive deficits, gait dysfunction, and weakness. A course of methylphenidate was trialed to support cognitive recovery. By day of discharge, he had achieved greater independence and mobility, but cognitive deficits persisted. Within three months, he was rehospitalized for NMDAR.

Setting: Inpatient Acute Rehabilitation Hospital and Outpatient Rehabilitation Clinic

Assessment/Results: At his initial clinic followup, therapy evaluations noted regression in prior rehabilitation gains. Neuropsychological evaluation revealed persistent impairments in processing speed, visual attention, and initiation - limiting his ability to return to work or drive. Methylphenidate was restarted to improve cognition and behavior. Outpatient therapy continuation and acquired brain injury program enrollment allowed the patient to make significant functional progress towards his post-rehabilitation discharge levels.

Discussion (relevance): We present a complex case where HSE likely triggered a cascade leading to right MCA stroke and SAH, which lead to functional deficits requiring acute rehabilitation. The subsequent NMDAR posed rehabilitation challenges due to regression in functional progress, highlighting the importance of longitudinal, multidisciplinary outpatient rehabilitation. Given a lack of standardized rehabilitation protocol for this phenomena, this case adds additional treatment examples to the current literature.

Conclusions: HSE may cause stroke and delayed onset NMDAR, requiring close monitoring by a longitudinal, multidisciplinary rehabilitation team after acute infection.