A pilot study on hypothalamo-pituitary-adrenocortical axis in primary hyperparathyroidism

作者：Rajput Rajesh; Bhansali Anil^*; Bhadada Sanjay Kumar; Behera Arunanshu; Mittal B R; Sialy Ravinder; Khandelwal N

来源：Indian Journal of Medical Research, 2009, 130(4): 418-422.

• Cortisol
• hyperparathyroidism
• osteoporosis

Background & objectives: Parathormone (PTH) and calcium, both have been shown to stimulate adrenal steroidogenesis in animal models and in vitro experiments. This is attributed to structural similarity between 15-25 amino acid region of the parathyroid hormone (PTH) and 1-11 amino acid region of adrenocorticotropin (ACTH). However, there are no in vivo human data regarding the effect of PTH-calcium axis on adrenocortical function.
Materials: Ten patients with primary hyperparathyroidism underwent evaluation for cortisol dynamics including 0800 h and 2000 h plasma cortisol on day 1, cortisol response to insulin induced hypoglycaemia (IIH) on day 2, and 1 mg overnight dexamethasone suppression test (ONDST) on day 4. Serum aldosterone was also measured at 0800 h in fasting state on salt ad libitum for three days. These parameters were repeated 3 months after curative parathyroidectomy.
Results: Basal plasma cortisol level at 0800 h and 2000 h were within upper normal range and loss of circadian rhythm in cortisol secretion was observed in half and forty per cent of patients had non-suppressibility with ONDST. The defined peak cortisol response to insulin induced hypoglycaemia (>550 nmol/l) was achieved in all and nearly one third of patients had exaggerated response (>2000 nmol/l). After curative parathyroidectomy, the abnormalities in circadian rhythm and non-suppressibility with ONDST continued to prevail in 40 per cent of patients. The peak cortisol response to IIH showed a decrement but remained higher than normal. No correlation was observed between circulating parathyroid hormone and calcium with cortisol levels. Serum aldosterone was in upper normal range pre- and postoperatively, though it decreased postoperatively, but it could not attain a statistical significance (P=0.5).
Interpretation & conclusion: Abnormalities in hypothalamo-pituitary-adrenocortical axis in primary hyperparathyroidism do occur, however these are inconsistent and do not recover in majority of patients even after 3 months of curative parathyroidectomy.

• 出版日期2009-10
• 单位河北医科大学