Altered parathyroid gland function in severely immunocompromised patients infected with human immunodeficiency virus

Several endocrine functions have been found disturbed in patients with acquired immunodeficiency syndrome (AIDS). However, no information is available on parathyroid function in these patients. Six patients with AIDS and 10 healthy volunteers underwent an EDTA infusion to induce hypocalcemia and stimulate PTH secretion. A group of 6 severely ill patients with malignancies was studied at baseline and served as additional controls for the effect of a severe disease per se. Baseline values showed that mean serum intact PTH concentration was lower in patients infected with the human immunodeficiency virus than in healthy volunteers (P < 0.04) as well as in patients with malignancies (P = 0.004). Whole blood calcium also tended to be lower in patients with the human immunodeficiency virus than in both control groups, the difference reaching the limit of statistical significance for the healthy controls only (P < 0.04). Mean serum magnesium, 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D concentrations were similar in both groups. Throughout the entire EDTA stimulation procedure, i.e. at any blood calcium concentration, serum intact PTH concentration remained lower in patients with AIDS than in healthy control subjects (P < 0.04, analysis of variance for repeated measurements). Basal and maximal secretion of PTH is reduced in patients with AIDS. The mechanisms underlying this finding remain speculative.