intelligence occurs in about 20% of children with the idiopathic form of hypoparathyroidism and the severity correlates closely with the period of untreated hypocalcemia Dry, scaly skin is a common finding, as is patchy alopecia Psoriasis or mucocutaneous candidiasis may be found on occasion Unusually brittle fingernails and hair are often found Hypoplasia of tooth enamel may be seen if hypoparathyroidism was present at the time of dental development Intestinal malabsorption and steatorrhea have been reported in association with hypoparathyroidism Management/Diagnostic Testing In most cases, the diagnosis of hypoparathyroidism is first considered when low serum calcium is found If an elevated phosphate accompanies low calcium, low or normal serum alkaline phosphate, and normal blood urea nitrogen, hypoparathyroidism is a likely possibility Finding a low or unmeasurable level of PTH in the presence of hypocalcemia and hyperphosphatemia makes the definitive diagnosis Because PTH increases cAMP levels in the urine, the excreted amount of cAMP in the urine is low in patients with hypoparathyroidism and rises briskly with the administration of exogenous PTH The presence of antibodies in other endocrine tissues or organs may help in delineating the cause of the hypoparathyroidism The acute management of hypoparathyroidism is essentially the management of the hypocalcemia (see Chapter 100 Renal and Electrolyte Emergencies ) Magnesium levels must also be checked, as hypomagnesemia is a rare but important etiology of hypocalcemia Longterm management consists of treatment with vitamin D, usually with one of its more active analogs—1,25-(OH)2 D3 (calcitriol) at 0.01 to 0.05 mCg/kg/day Supplemental oral calcium is almost always necessary The goals of long-term therapy are to maintain the serum calcium in the lower range of normal and to avoid both vitamin D toxicity and hypercalcemia A subcutaneous preparation of recombinant PTH is now available, but uncommonly used for the long-term management of hypoparathyroidism given experimental increases in the incidence of osteosarcoma in animal studies Clinical Indications for Discharge or Admission Asymptomatic patients may be treated as outpatients with close follow-up RICKETS Goals of Treatment To initiate vitamin D (and potentially calcium treatment) to normalize serum phosphate and effect positive changes on radiographs To avoid a potentially dangerous drop in calcium with initiation of treatment CLINICAL PEARLS AND PITFALLS