Ascites, Pleural, and Pericardial Effusion in Primary Hypothyroidism: A Rare Case Report

Hypothyroidism is caused by a deficiency of thyroid hormones and is a common endocrine disorder worldwide. It can affect nearly every organ, resulting in multiple clinical manifestations. Ascites, pleural effusion, and pericardial effusion, although less frequent than peripheral edema, can also be present. These manifestations are thought to be caused by increased vascular permeability to albumin, extravasation of mucopolysaccharides, and inappropriate antidiuretic hormone secretion. Most effusions in hypothyroid patients resolve with thyroxine replacement therapy. However, due to the insidious and nonspecific nature of these symptoms, hypothyroidism is seldom considered a differential diagnosis. We report a case of a 48-year-old male with pericardial effusion, pleural effusion, and ascites due to primary hypothyroidism. Although isolated effusions can be frequent in patients with hypothyroidism, the presentation of Hashimoto's thyroiditis as a combination of pericardial effusion, pleural effusion, and ascites is extremely rare. With this case report, we highlight the importance of considering hypothyroidism as a possible cause of unexplained polyserositis, even in the absence of other signs and symptoms.