[Serum striated muscle enzymes in autoimmune hypoparathyroidism]

Elevated serum levels of creatine phosphokinase (CPK) and lactate dehydrogenase (LDH) are generally present in cases of muscle or heart disease, though there are some exceptions. We treated a 56-year-old man diagnosed as suffering from primary idiopathic hypoparathyroidism (PIHP). The neurologic examination was normal, but serum levels of CPK and LDH, and especially isoenzymes of striated muscle, were elevated. Elevated levels of these enzymes in PIHP are rare. In this case they most probably leaked from muscle into the blood circulation after changes in the muscle cell membrane due to hypocalcemia.