Its not always dementia: A rare case of vzv encephalitis
Saeed A, Assar S, Ali H, and Heidemann D. Its not always dementia: A rare case of vzv encephalitis. J Hosp Med 2017; 12(s2)
Journal of Hospital Medicine
Case Presentation: An 84 year old female presented to the emergency department after developing new onset severe left ear pain, swelling and flu like symptoms. Physical examination revealed stable vitals and an edematous and tender left ear auricle associated with left sided cervical lymphadenopathy. She was diagnosed with Otitis Externa and discharged with oral and topical antibiotics. The following day, she was called back due to a positive blood culture which was later determined to be a contaminant. During her admission, she had decreased cognition and difficulty with word finding. Neurological examination determined that patient had slow speech and inappropriately answered questions however no focal neurological deficits were noted. It was thought that she may have had underlying dementia given her advanced age, or delirium. However, when her primary care physician came to visit her, she noted a marked change from baseline mental status. This prompted a lumbar puncture. Cerebrospinal fluid studies were consistent with viral meningitis with a white blood count of 405 with 99% lymphocytes, elevated protein count at 121, normal glucose at 65. She was started on intravenous acyclovir while awaiting PCR results. Three days thereafter the patient was noted to have developed vesicles on her left upper back and ear. PCR results came back positive for Varicella Zoster virus confirming the diagnosis of VZV encephalitis. Her total length of stay was 7 days and she was discharged with IV antivirals to complete a 21 day course. Throughout her stay her mental status improved and over several weeks her cognitive deficits completely resolved. Discussion: Aseptic encephalitis as described in this case scenario is one of the atypical presentations of VZV infection and can occur in both immune competent and immune compromised individuals and the overall incidence is approximately 0.5%. It should be noted that the classic vesicular eruption associated with aseptic meningitis may occur at any point either prior to or after meningeal irritation and also in the complete absence of cutaneous eruption—in which case it is known as zoster sine herpete. This inevitably leads to a delay in diagnosis and treatment resulting in higher morbidity and mortality rates. VZV aseptic meningitis has similar CSF findings to all other etiologies of aseptic meningitides and diagnostic confirmation is determined most commonly by CSF PCR analysis. The delay in initiating treatment in this case scenario was due to the fact that the cutaneous manifestations occurred later; the physicians involved in the patients care anchored on the diagnosis made in the emergency department. Additionally, changes in the patients’ mental status were attributed to her advanced age and to dementia, and a baseline mental status was not established.Elderly patients are often assumed to have dementia or delirium which can lead to a missed diagnosis and the involvement of the patients’ family or communication with their primary care physician is a way to rectify the mistake. Had the patient been young, a change would have been visible earlier resulting in an earlier diagnosis and treatment. Conclusions: The purpose was to present a rare case of VZV encephalitis and the difficulty of its diagnosis. If not for the delayed presentation of clinical signs and symptoms, the assumption of baseline dementia and delirium in an elderly patient, and anchoring on the diagnosis of the emergency department, this case would have been resolved earlier.