An autopsy case report of a patient with myxedema coma

Abstract Background Myxedema coma is a rare disease in which the underlying metabolic function is impaired due to hypothyroidism. Although myxedema coma has a very low prevalence, it has been associated with a high mortality rate. However, autopsy cases of myxedema coma have not yet been reported. Case presentation: This study presents an autopsy case of myxedema coma in an 82-year-old man with hypothyroidism, despite receiving treatment with levothyroxine. The patient suffered from head trauma and cold exposure, resulting in disturbance of consciousness and hypothermia. Upon arrival at our hospital, the patient exhibited severely impaired consciousness and had a body temperature of 27.2℃, oxygen saturation of 71%, heart rate of 40 beats/min, and hypotension. The thyroid hormone levels decreased with the thyroid-stimulating hormone level being 14.10 µIU/mL and free T4 being 0.57 ng/dL. Therefore, the patient was diagnosed with myxedema coma and underwent levothyroxine treatment (200 µg daily), noninvasive positive pressure ventilation, and adrenaline administration. However, the patient did not respond to those treatments and died six days after admission. The autopsy findings indicated pericardial and pleural effusions and, histologically, edematous adipose tissue infiltration containing mucopolysaccharides throughout multiple organs, such as the heart, thyroid, pancreas, and kidney. Conclusions Although gelatinous degeneration of bone marrow tissue due to mucopolysaccharides with edema was previously reported in patients with severe hypothyroidism, no reports on the other visceral adipose tissues were found. This autopsy case might present pathological changes resembling gelatinous degeneration in various organs which are caused by myxedema coma for the first time.