Elevated muscle enzymes and muscle biopsy in idiopathic hypoparathyroidism patients

To study idiopathic hypoparathyroidism (IHP) myopathy and its pathogenesis by histology method.

We retrospectively analyzed the clinical data of nine IHP patients during the years 2006-2010.

We found that: 1) there was an inverse relationship between the decreased serum calcium level and the elevated muscle enzymes level; 2) the IHP patients had mild-to-moderate muscle cells vacuolar degeneration and focal hyaline degeneration by hematoxylin-eosin (HE) staining; 3) except for 2 patients, the others' muscles striations were undetectable by phosphotungstic acid hematoxylin staining; 4) 2 patients with extremely high level of creatine kinase and relatively longer disease duration had muscle atrophy, multiple focal muscle fiber hyaline degeneration and sarcolemma cells hyperplasia by HE staining; 5) all patients had different degree of immune complex deposition along the muscle cell membranes by immunofluorescence staining.

The patients with IHP had some histological changes in skeletal muscles but with no specificity. The changes in muscles and the elevated serum muscle enzymes were related to hypocalcemia. The severity of changes in muscles was related to the duration of hypocalcemia and not only to its degree.