(P79) "My Brain Is Not Right"

78 year old female with renal amyloidosis, Waldenstroms Macroglobulinemia, lymphoma, HFpEF, ESRD on peritoneal dialysis (PD) presented with altered mental status.
History of Present Illness: She initially presented to her primary care doctor for facial rash and was started on renally-dosed valacyclovir for herpes zoster and was told that zoster had not spread to her eyes. However, that evening the patient's husband reported that she was agitated and having difficulty with word finding and operating her phone. She also had difficulty setting up her PD and could not remember how to connect it. She was also experiencing auditory and visual hallucinations. The next morning her mental status had not improved; this prompted her spouse to bring her in to the emergency department (ED).

Pertinent Physical Exam: VS: BP 157/80 | HR 84 | RR 19 | Temp 96.8 | SpO2 100%
Neurologic: Waxing and waning mental status; occasionally disoriented and unable to state date or where she is. During interview patient was agitated and stated that "her brain wasn't right and she felt as if she was going crazy". She was not able to tell ED providers any events that led up to the ED visit. Speech is not slurred. No facial droop. Moving all extremities, no focal weakness. No ataxia.
Skin: Crusted vesicular lesions about the V1 distribution left side of face

Pertinent Laboratory Data: Labs: WBC 24.1
BUN 81, Cre 10.91
BNP 419.4, Trop 0.123
CT Head: microvascular changes

Dosed w/ pipercillin-tazobactam 3.375g, vancomycin 1g after blood cultures were sent; no antivirals given, out of concern for neurologic effects of valacylovir toxicity as the cause of patient's altered mental status.
Admitted to medicine for altered mental status, presumed secondary to valacyclovir toxicity.
Given V1 distribution of zoster and clinical suspicion of varicella encephalitis, lumbar puncture was eventually recommended and performed. Cerebrospinal fluid was positive for varicella zoster.

Case

Discussion: It is critical for emergency department providers to consider Varicella Zoster encephalitis in immunocompromised and renal patients with altered mental status and recent rash. Initial working diagnosis for admission was valacyclovir toxicity given patient's renal failure. ED staff had discussed with her nephrologist who assured team that her valacyclovir was appropriately dosed for her GFR; nevertheless, antivirals were deferred in the ED out of concern for neurologic effects of valacyclovir toxicity as the cause of her presentation. Given V1 distribution of zoster and clinical suspicion of varicella encephalitis, lumbar puncture was eventually recommended and performed, which was positive for varicella zoster and the patient was started on empiric IV acyclovir.

In the hospital, patient continued to demonstrate poor mental status, AOx0 non-verbal minimally responsive to stimulus. MRI was Brain done, which was negative for other abnormalities. Patient was placed on vEEG which was notable for focal right temporal seizure activity, concerning for non-convulsive status epilepticus. Loaded with keppra 1g and ativan 2mg. Patient was transferred to MICU due to worsening mental status, where she had a prolonged two-month long course with many complications.

It is critical for emergency department providers to consider varicella zoster encephalitis in immunocompromised and renal patients with altered mental status and recent rash. In this case, ED staff deferred antiviral administration and lumbar puncture, instead anchoring on the diagnosis of valacyclovir toxicity. Valacyclovir can cause neurologic effects and altered mental status especially in renal patients, and this is an important consideration. However, early lumbar puncture and early antivirals might have given this patient a better outcome; instead, lumbar puncture was not performed until more than ten hours after initial presentation to the emergency department, and the diagnosis of varicella zoster encephalitis made.