Case 3-2019: A 70-Year-Old Woman with Fever, Headache, and Progressive Encephalopathy

MR Imaging Patterns and Prognosis in Powassan Virus Encephalitis

BACKGROUND

Powassan virus (POWV) encephalitis is an arbovirus infection and the only tick-borne encephalitis serogroup which is present in mainland North America. The magnetic resonance (MR) imaging described with POWV encephalitis is varied, nonspecific, and limited in number, and as such, imaging patterns and outcomes with this arbovirus infection are not well appreciated.

METHODS

A case report and literature review of the MR imaging associated with POWV encephalitis and correlate of the MR pattern with outcome is considered.

RESULTS

The cerebellar dominant MR imaging pattern was identified in 50% of POWV encephalitis cases and was associated with a 60% fatality rate. POWV encephalitis with prominent cerebellar involvement on MR imaging responded to intravenous steroid.

CONCLUSIONS

A cerebellar dominant MR pattern in POWV encephalitis was common, associated with a poor prognosis, and recognition could change management from supportive to life-saving.

A comprehensive neurological perspective on tick-borne flaviviruses, with emphasis on Powassan virus

Powassan virus (POWV), a tick-borne flavivirus transmitted primarily by Ixodes ticks, poses a significant threat as it can lead to severe neuroinvasive illness. This review delves into the nuanced clinical presentation of Powassan infection, a challenge in diagnosis exacerbated by the absence of an available vaccine. Over the past decade, the prevalence of POWV has surged in North America, necessitating a thorough examination of its neurological manifestations alongside tick-borne encephalitis virus (TBEV). A comprehensive literature search conducted up to January 2024 revealed 135 cases of neurological symptoms associated with either Powassan or TBEV infection. Notably, severe occipital headache emerged as the most prevalent symptom (22.75%), followed by meningoencephalitis (10.34%), seizures (8.27%), and flaccid paresis (6.8%). Additional manifestations included poor balance, wide gait, dysarthria, facial nerve palsy, seizure, slurred speech, and absent deep tendon reflexes. Tragically, nine cases resulted in fatal outcomes attributed to POWV infection. This analysis highlights the intricate spectrum of neurological symptoms associated with Powassan infection and underscores the necessity for heightened awareness among medical practitioners, particularly in regions with a higher prevalence of the virus. The complexity of symptoms emphasizes the need for further research to unravel the factors contributing to this diversity. Additionally, exploring potential treatment avenues and vaccine development is crucial in addressing the rising threat posed by POWV, ultimately enhancing our ability to manage and prevent severe neurological outcomes.

Identifiable relatives in the family history: not without individual consent

The family history is a traditional section of the clinical record. Data on family members in the clinical record may be anonymous but yet these may be easily identifiable; therefore, exposing the relatives of the patient to the fact that a written record is produced, mentioning them, without their consent. This is in direct contradiction with European data protection and other regulations and in contradiction with a reasonable ethical perspective. For the purpose of obtaining an image of the present state of affairs, we used as a convenience sample, the series of Case Records published in 2019 in The New England Journal of Medicine (January to December). From a total number of 40 reports, identifiable relatives were present in 30. The number of identifiable relatives varied between none and 6. It is not the right of each individual to disclose sensitive clinical information regarding other persons, without consent from these latter. Family history should no longer include identifiable relatives, unless consent is obtained from each identifiable person. The authors offer the following guidelines on this topic: (1) Do not mention any identifiable relative of the patient in the medical history without consent from the said relative; (2) Do not mention in the family history clinical conditions seemingly unrelated to the present clinical situation; (3) Do not mention in the family history clinical conditions that the patient does not (him/) herself have and that may be seen as social stigmata; (4) Consult the institutional Ethics committee in case of reasonable doubt.