Severe rhabdomyolysis and acute renal failure in an adolescent with hypothyroidism.

Hypothyroidism has been reported rarely as the cause of rhabdomyolysis in adults and children. We present here a non-compliant adolescent with a diagnosis of hypothyroidism who developed rhabdomyolysis and acute renal failure with no additional predisposing factor. A 13-year-old girl with a previous history of hypothyroidism due to thyroid hypoplasia presented with generalized myalgia, malaise, vomiting, and oliguria lasting for three days. Neurological examination revealed bilateral marked weakness and tenderness of muscles of both lower and upper extremities. Urine had bloody appearance and urine analysis showed blood reaction with dipstick test, but there were no erythrocytes on microscopic examination. Serum creatine phosphokinase and myoglobin levels were elevated. Thyroid stimulating hormone (TSH) levels were high, and free thyroxine (T4) and triiodothyronine (T3) levels were low, compatible with uncontrolled hypothyroidism. Renal function tests showed acute renal failure. Other causes of rhabdomyolysis such as muscular trauma, drugs, toxins, infections, vigorous exercise, and electrolyte abnormalities were excluded. Hemodialysis was administered for 24 sessions. After L-thyroxine therapy, thyroid function tests normalized, muscle strength improved, serum muscle enzyme levels returned to normal levels, and renal function tests recovered. One must be aware that rhabdomyolysis may develop in a non-compliant patient with hypothyroidism.