PC2156: Wernicke Encephalopathy as a Complication of COVID-19: A Pediatric Case Report

Introduction: Wernicke encephalopathy is the result of thiamine (vitamin B1) deficiency and is characterized by the clinical triad of oculomotor dysfunction, ataxia, and altered mental status. It is underdiagnosed as very few patients present with all three symptoms.

Case Description: A 14-year-old previously healthy female presented to the emergency department with three days of altered mental status and abnormal gait. Parents noted avoidance of rightward gaze and one episode of urinary incontinence. Ten months prior to presentation, the patient was diagnosed with COVID-19 complicated by anosmia and dysgeusia. Since her infection, she had lost 22 kg, and parents reported that her diet had only consisted of saltine crackers for the last few weeks. She was afebrile, tachycardic, and hypertensive on arrival. Review of her growth chart revealed 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. No nystagmus was noted, but assessments of extraocular movements, cranial nerves, and strength were limited as she could only follow simple commands. Reflexes, tone, and heel to shin testing were normal. She had a blunt, flat affect with delayed speech. CMP showed a potassium of 2.7 and sodium of 126. CBC, TSH, and ammonia were within normal limits. Urinalysis was negative for infection, and UDS was negative. Noncontrast head CT and CT angiogram were unremarkable. Broad viral testing was negative as were autoimmune and paraneoplastic panels. Routine CSF studies were normal. EEG did not demonstrate seizure activity but was consistent with encephalopathy. The patient’s mental status quickly deteriorated, and she was transferred to the PICU for intubation to protect her airway. She became hypotensive requiring pressors and lactic acid was found to be 11.6, consistent with shock. BNP was 6,672 and troponin was mildly elevated 25. Echo showed normal cardiac function. Brain MRI demonstrated bilateral signal abnormalities in the thalami, midbrain, and inferior colliculi. On repeat MRI, these progressed to include the hypothalamus, raising concern for Wernicke encephalopathy. Thiamine (vitamin 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-related dysgeusia and resultant anorexia leading to nutritional deficiency. Additionally, this patient demonstrated manifestations of wet beri beri, a cardiovascular complication of thiamine deficiency in which peripheral vasodilation leads to high output heart failure. These sequelae of thiamine deficiency are rare in pediatrics.

Conclusion: This case elucidates the importance of considering nutritional deficiency in the differential diagnosis for encephalopathy. Furthermore, this case highlights the potential morbidity associated with persistent dysgeusia, contributing to the understanding of the long-term effects of COVID-19.