Subacute Development of Parkinsonism as a Clinical Manifestation of Powassan Virus Neuroinvasive Disease
Objective:
Address the rising incidence of Powassan virus neuroinvasive disease. Discuss the breadth of clinical presentation. Emphasize the increased rate of neurologic morbidity associated with Powassan virus neuroinvasive disease.
Background:
Powassan virus is a tick-borne flavivirus endemic in the US, Canada, and Russia. In the US, infections are most common in the Great Lakes region and northeastern states. Overall incidence has been steadily rising over the past decade. Infection is rare but can be potentially life threatening. Approximately half of all patients with Powassan virus neuroinvasive disease will experience permanent neurologic sequelae, most commonly cognitive decline, severe headache, or hemiplegia. We present the case of a 70-year-old female who developed a subacute post-encephalitic parkinsonian syndrome secondary to Powassan virus meningoencephalitis. There is only 1 other case report detailing post-encephalitic parkinsonism secondary to Powassan virus neuroinvasive disease that occurred 16 months after initial presentation. This case is unique in its subacute onset of parkinsonism of 1-2 weeks.
Design/Methods:
Review of EMR. PubMed search for “Powassan virus”, “encephalitis”, and “parkinsonism."
Conclusions:
Parkinsonism is an exceedingly rare complication of any infectious meningoencephalitis, especially in Powassan virus with 1 other documented report. This case demonstrates the devastating and long-lasting sequelae that can manifest relatively early on during the course of neuroinvasive disease. Thus, it is imperative that neurologists and infectious disease providers in endemic areas be familiar with the risk factors and clinical presentation of this disease to better understand prognosis and anticipate long-term care needs of their affected patients.