1.
Paradoxical Response of Parathyroid Hormone to Vitamin D-Calcium Supplementation in Indian Children.
Mandlik, RM, Mughal, ZM, Khadilkar, AV, Ekbote, VH, Kajale, NA, Patwardhan, VG, Khadilkar, VV, Padidela, R
The Journal of pediatrics. 2020;:197-203
Abstract
OBJECTIVES To investigate the effect of oral vitamin D-calcium supplementation on serum intact parathyroid hormone (PTH), calcium, phosphorous, and alkaline phosphatase (ALK-P) concentrations in children with habitually low calcium intakes. STUDY DESIGN In this follow-up study to a randomized controlled trial that aimed to assess the effect of vitamin D-calcium supplementation on immunity, data related to dietary intake, anthropometry, and biochemistry [serum 25(OH)D and bone profile] were collected from 178 children-79 in the vitamin D group and 99 in the non-vitamin D group. RESULTS Dietary calcium to phosphorus intake ratio was 0.4:1. Baseline serum 25(OH)D concentration was 58.2 ± 10.9 nmol/L; 66% children were vitamin D sufficient and none deficient. After supplementation, vitamin D group, compared with the non-vitamin D group, had significantly (P < .05) greater 25(OH)D (83.9 ± 30.1 nmol/L vs 58.3 ± 15.7 nmol/L), significantly greater PTH (6.7 ± 3.6 pmol/L vs 5.5 ± 3.2 pmol/L), and positive correlation (rs = 0.24) between serum 25(OH)D and PTH (vs negative correlation [rs = -0.1] in non-vitamin D group). Mean concentrations of serum bone measures in the vitamin D group were calcium (2.2 ± 0.1 mmol/L), phosphorus (1.7 ± 0.2 mmol/L), and ALK-P (178.7 ± 40.7 IU/L). At follow-up, 1-year post-supplementation, in the vitamin D group, PTH concentrations continued to remain high (but not significantly different from levels at 6 months), with low normal serum calcium, high normal phosphate, and ALK-P in reference range. CONCLUSIONS In children who are vitamin D sufficient but with habitually low dietary calcium intake, vitamin D-calcium supplementation paradoxically and significantly increased serum PTH concentrations with no apparent effect on other bone biochemistry. Chronic low dietary calcium to phosphorus ratio is likely to have caused this paradoxical response.
2.
The medical and surgical treatment in secondary and tertiary hyperparathyroidism. Review.
Cocchiara, G, Fazzotta, S, Palumbo, VD, Damiano, G, Cajozzo, M, Maione, C, Buscemi, S, Spinelli, G, Ficarella, S, Maffongelli, A, et al
La Clinica terapeutica. 2017;(2):e158-e167
Abstract
INTRODUCTION Hyperparathyroidism is an alteration of the pathophysiological parathyroid hormone (PTH) secretion due or an independent and abnormal release (primary or tertiary hyperparathyroidism) by the parathyroid or an alteration of calcium homeostasis that stimulates the excessive production of parathyroid hormone (secondary hyperparathyroidism). AIMS There is not a standard, clinical or surgical, treatment for hyperparathyroidism. We review current diagnostic and therapeutic methods. DISCUSSION In secondary hyperparathyroidism (2HPT) there is a progressive hyperplasia of the parathyroid glands and an increased production of parathyroid hormone. Several causes are proposed: chronic renal insufficiency, vitamin D deficiency, malabsorption syndrome. The tertiary hyperparathyroidism (3HPT) is considered a state of excessive autonomous secretion of PTH due to long-standing 2HPT and it's usually the result of a lack of suppression in the production of PTH. The pathophysiological implications are both skeletal and extraskeletal: it damages the cardiovascular system, nervous system, immune, hematopoietic and endocrine system. The introduction of new drugs has improved the survival of these patients, allowing the inhibition of the synthesis of PTH. Indication for surgical treatment is unresponsive medical therapy. CONCLUSIONS There are no large prospective studies that comparing the medical and surgical treatment. The choice is not unique and we have to consider the singolar case and the clinical condition of the patient.