(Kiosk 3) Insult to Injury: Recognition and Treatment of Progressive Catatonia in a Patient Recovering from Herpes Simplex Encephalitis

Case Diagnosis: A 78-year-old man who presented with status epilepticus requiring ICU admission, found with herpes simplex virus-1 (HSV-1) encephalitis and noted at acute rehabilitation with progressive catatonic features out of proportion to neuroimaging findings.

Case Description or Program Description: The patient arrived at acute rehabilitation 1 month from initial presentation with profound cortical deficits involving impaired attention, executive function, and speech apraxia with 50% intelligibility. Despite multidisciplinary therapies, he exhibited decline in environmental interaction with progressive mutism and paratonia. Repeat MRI showed improvement of right temporal enhancement, EEG was negative for epileptiform activity, and infectious workup was unrevealing. His catatonic features prompted suspicion for an ongoing encephalopathic process. We administered a five-day course of high dose steroids using solumedrol 1g IV daily for possible anti-NMDA autoimmune encephalitis, an infrequent but known sequelae of HSV encephalitis. The patient made noticeable gains within 24 hours, especially in motor and speech initiation. Given this improvement, we pursued further treatment with a five-day course of intravenous immune globulin (IVIG) therapy.

Setting: Tertiary care adult rehabilitation hospital

Assessment/Results: At discharge the patient had resolution of paratonia and ambulated 150 feet with a rolling walker at a supervision level. He continued with frequent distractibility and perseveration on off-topic information but his speech apraxia had improved to 100% intelligibility, and he was able to hold short conversations when redirected.

Discussion (relevance): Anti-NMDA autoimmune encephalitis is a well-documented but often unrecognized sequelae of HSV encephalitis which usually develops 2-4 weeks after initial presentation. This time frame makes it a unique pathology in that it can be optimally diagnosed and treated in the acute rehabilitation setting.

Conclusions: Patients recovering from HSV encephalitis will often require inpatient rehabilitation. Physiatrists should remain vigilant for underlying processes causing relapse or continuation of encephalopathic symptoms out of proportion to diagnostic imaging in this population.