This disorder is caused by decreased secretion of parathyroid hormone (PTH) by the chief cells of the parathyroid glands, resulting in decreased resorption of bone salts with resultant hypocalcemia. Lab abnormalities include the above-mentioned low calcium levels, hyperphosphatemia, low PTH, and normal alkaline phosphatase. Associated symptoms include mucocutaneous candidiasis, cataracts, pernicious anemia, alopecia, vitiligo, tetany, and paraesthesias. Calcification of the basal ganglia are common but clinical Parkinsons disease is unusual. Etiologies include hypomagnesemia, postoperatively for neck surgery (may be transient or permanent), infiltration of the parathyroids with iron in hemochromatosis or with copper in Wilsons disease, and oridiopathic aplasia of the glands (DiGeorge syndrome, which is rare). Diagnosis may be made in hypocalcemic patients with low PTH levels after alkalosis, hypomagnesemia, and hypoalbuminemia have been excluded.