Rhabdomyolysis and Pericardial Effusion Resulting From Hypothyroidism Associated With Acute Myeloid Leukemia

Hypothyroidism prevalence can reach 11.7%, though rhabdomyolysis is rare, complicating 3% to 6% of cases with pericardial effusion. This report details a rare case of an adult with leukemia developing both simultaneously.

A 67-year-old male with acute myeloid leukemia, after standard chemotherapy (chemo), had fatigue, blurred vision, dyspnea, progressive myalgias, and syncopal episodes. Tests showed elevated muscle enzymes, including creatine kinase (CK), lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, as well as increased myoglobin levels, and an 18-mm pericardial effusion. Thyroid function tests revealed hypothyroidism, complicated by rhabdomyolysis and cardiac tamponade. Levothyroxine replacement therapy led to significant short - term improvements.

The mechanisms of hypothyroidism - induced rhabdomyolysis and pericardial effusion are complex. Thyroid hormone deficiency causes metabolic and muscle energy issues, and increased capillary permeability and mucopolysaccharide deposition play roles. Acute leukemia and hypothyroidism may coincidentally co-occur, and leukemia treatments can worsen thyroid problems. For patients with relevant symptoms, CK, myoglobin, and cardiac ultrasound tests are crucial, along with hormone replacement and support care.

The symptoms of overt hypothyroidism can be masked by coexisting acute myeloid leukemia. For patients with unexplained muscle aches and high CK, consider hypothyroidism. Early thyroid hormone replacement may be highly effective.