Abstract
Thiamine deficiency can cause various clinical manifestations. Wet beriberi, a phenotype of thiamine deficiency, is often underdiagnosed in clinical practice due to the nonspecificity of symptoms. An 83-year-old man presented to a primary care clinic with a two-month history of progressing edema in the scrotum and lower extremities. The patient reported a weight gain of 10 kg and was treated with diuretics. However, his condition did not improve even after four weeks. The patient was referred to our hospital for further cardiac evaluation. Transthoracic echocardiographic findings were suggestive of a high cardiac output (CO) state, and the thiamine level was decreased. Further medical interview revealed that the patient had a habit of eating two or three large bowls of white rice with a few side dishes for breakfast and dinner. The hemodynamic evaluation revealed high CO and low systemic vascular resistance. The patient's weight decreased from 56.6 to 52.4 kg in the first 2 days after thiamine administration. Six days later, his weight further decreased to 50.8 kg and edema disappeared completely. Clinicians should be aware that excessive consumption of white rice with few side dishes may lead to thiamine deficiency. This case highlights the importance of considering wet beriberi as a cause of excessive edema with high CO state.