Acute Thiamine Deficiency Detected by Video Head Impulse Test in a Patient with Gastric Mucosa-Associated Lymphoid Tissue (MALT) Lymphoma

Abstract

Thiamine deficiency may cause Wernicke encephalopathy (WE) characterized by ataxia, ophthalmoplegia, and confusion. Aside from the triad of cardinal symptoms, selective or predominant impairments of bilateral horizontal canals may be observed in WE. Here, we report a patient with gastric mucosa-associated lymphoid tissue (MALT)-lymphoma complicated by an early stage of WE due to thiamine deficiency manifesting bilateral vestibular dysfunctions. A 78-year-old man recently diagnosed gastric MALT-lymphoma presented with dizziness and disequilibrium for several weeks. He showed mild imbalance while tandem walking and abnormal catch-up saccades bilaterally during bedside head impulse test (HIT). Video HIT revealed decreased vestibulo-ocular reflex gains with catch-up saccades for the bilateral horizontal and several vertical canals. Diagnostic work-up demonstrated decreased serum thiamine and lesions in the mammillary body and periaqueductal gray matter on brain magnetic resonance images. Furthermore, with thiamine replacement, his clinical symptoms were markedly improved. Also, vestibular symptoms and signs may be an early manifestation of WE, and video HIT could be a useful diagnostic tool to aid early detections.