Acute renal failure: a rare presentation of hypothyroidism.

Thyroid hormones affect the function of almost every body organ, and thyroid dysfunction produces a wide range of metabolic disturbances. Severe hypothyroidism is associated with significant effects on the kidney. The pathophysiology is thought to be multifactorial, while the exact mechanism remains unclear. Hypothyroidism as a cause of renal impairment is usually overlooked, leading to unnecessary diagnostic procedures. We describe two patients with acute renal failure due to severe hypothyroidism in whom thyroid hormone substitution therapy led to a significant improvement in renal function.