Case Presentation: A 14-year-old previously healthy female presented to the Emergency Department with 3 days of fluctuating mental status and gait difficulty. Parents noted one episode of urinary incontinence and endorsed avoidance of right sided gaze. Ten months prior to these symptoms, the patient was diagnosed with COVID-19 complicated by anosmia and dysgeusia. Since her infection, she had lost 22 kg and parents described that her diet consisted of only saltine crackers for the last 3 weeks. On physical exam, blood pressure was 148/103, heart rate was 111, and respiratory rate was 18. Growth chart showed a decrease in weight from the 99th percentile to the 85th percentile over ten months. Mucous membranes were dry. She was oriented only to person, followed simple commands and withdrew to pain. No nystagmus was noted, but assessment of extra ocular movements, cranial nerves and strength was limited without her cooperation. Reflexes and tone were normal. Heel to shin testing was unremarkable. Her affect was described as blunt and flat with delayed speech.CMP showed a potassium of 2.7 and a sodium of 126. CBC, TSH, and ammonia were normal. Urinalysis demonstrated no evidence of infection. Drug screen was negative. Noncontrast head CT and CT angiogram were unremarkable. Routine CSF studies were normal. EEG did not demonstrate seizure activity but was consistent with encephalopathy. Broad viral testing was unremarkable. Autoimmune and paraneoplastic panels were negative. The patient’s mental status quickly deteriorated, and she was transferred to the PICU for intubation to protect her airway. She became hypotensive and lactic acid was elevated to 11.6 mmol/L consistent with shock. She required a vasopressor drip. BNP was 6,672 ng/L. Echocardiogram demonstrated normal cardiac function. Brain MRI demonstrated bilateral signal abnormalities in the thalami, midbrain, and inferior colliculi which on repeat MRI progressed to include the hypothalamus, raising the concern for Wernicke encephalopathy. Thiamine (B1) level ultimately returned low at 20 nmol/L.

Discussion: The diagnosis of non-alcoholic Wernicke encephalopathy was made, thought to be secondary to COVID-19 dysgeusia and resultant anorexia leading to nutritional deficiency. Thiamine supplementation was started with subsequent improvement in her mental and cardiovascular status. Wernicke encephalopathy is the result of thiamine deficiency and characterized by the clinical triad of oculomotor dysfunction, ataxia, and altered mental status. It is well documented that symptoms can rapidly worsen if glucose is given prior to thiamine supplementation. It is under-diagnosed as very few presentations include all three symptoms. Additionally, this patient demonstrated manifestations of wet beri beri, a cardiovascular complication consisting of peripheral vasodilation leading to high output heart failure. These complications of thiamine deficiency are rare in pediatrics.

Conclusions: This case elucidates the importance of considering nutritional deficiencies as a cause of encephalopathy. Furthermore, this case highlights the morbidity of persistent dysgeusia contributing to the expanding sequelae of COVID-19.