Hyperthyroidism With Non-chylous Ascites: A Case Report

Ascites is the accumulation of fluid in the abdominal cavity and is commonly attributed to various etiologies, including portal hypertension and peritoneal diseases. Hyperthyroidism is rarely associated with ascites, which is typically chylous and accompanied by high central venous pressure. We present a unique case of a 57-year-old woman with untreated hyperthyroidism who manifested non-chylous ascites without evidence of high venous pressure. Initially presenting with left lower leg pain, the patient presented with leg edema, abdominal distention, and diarrhea. A range of diagnostic tests ruled out common etiologies of ascites, such as liver cirrhosis, renal impairment, heart failure, infection, and malignancy. Ascites was characterized by low triglyceride levels, while no evidence of high venous pressure was found. Notably, the patient showed decreased levels of rapid turnover proteins, suggesting hypercatabolism and insufficient protein synthesis due to hyperthyroidism. Upon the initiation of antithyroid therapy, the patient's symptoms markedly improved. In conclusion, this report highlights a rare manifestation of hyperthyroidism that resulted in non-chylous ascites without high venous pressure. This underscores the need to include hyperthyroidism in the differential diagnosis of unexplained ascites, particularly in cases in which classical hyperthyroid symptoms are absent.