Rhabdomyolysis in four children was evaluated by bone scintigraphy using 99mTecnetium-methyldiphosphate (99mTc-MDP). The ages of the patients ranged from 7 to 14 years old. The causes of rhabdomyolysis were toxic shock syndrome in one patient, excessive exercise in one patient and cardiopulmonary arrest after cardiac surgery and after drowning in two patients. Peak serum creatine kinase (CK) and myoglobin (Mb) levels ranged from 5, 093 to 91, 150IU/l and 7, 486 to 111, 900ng/ml, respectively. Peak serum CK and Mb levels reached during the period from the first to third ICU day. Renal impairment occurred in the patient with toxic shock syndrome. After treatment with continuous hemodiafiltration, the renal impairment improved. Bone scintigraphy using 99mTc-MDP was performed during the period from the third to fifth ICU day. Abnormal accumulation of radioactivity was found in the two patients in whom rhabdomyolysis had been caused by excessive exercise and cardiopulmonary arrest after drowning. Despite the fact that peak CK raised to 12, 500IU/l in the patient of toxic shock syndrome, abnormal accumulation of radioactivity was not found. It was shown that bone scintigraphy using 99mTc-MDP is available for evaluation of rhabdomyolysis in children as it is in adults. However, in children with rhabdomyolysis, greater elevation of CK may be required to detect abnormal accumulation of radioactivity by bone scintigraphy using 99mTc-MDP compared with that in adults.
Hypothermia is usually caused by exposure to cold ambient temperatures. Some patients, however, have no obvious historyof cold exposure. Hypothyroidism should be recognized as a cause of hypothermia in certain situations. We report a case of transient central hypothyroidism presenting as hypothermia. A 74-year-old woman presenting with a disturbance in consciousness for the second time was transferred to our department because of deep hypothermia without exposure to cold ambient temperatures. Active rewarming normalized her body temperature, but her consciousness disturbance persisted. We performed an endocrinological examination to reveal the cause of the consciousness disturbance and subsequently diagnosed her as having hypothyroidism, based on a low serum-free T4 level. An additional thyrotropin-releasing hormone (TRH) test showed a decrease in thyroid-stimulating hormone (TSH) in response to TRH, suggesting that the hypothermia was caused by central hypothyroidism. Hormone supplementation was performed, and her consciousness disturbance rapidly improved. Since her serum-free T4 level gradually increased over the course of several weeks, we speculated that her hypothyroidism was transient. An endocrinological examination should be considered in patients who present with hypotermia accompanied by a consciousness disturbance to reveal the underlying disorder.