25-hydroxyvitamin-d-2 and Hyperparathyroidism--Primary

Vitamin D via its receptor has essential actions on parathyroid cells, inhibiting PTH secretion, and parathyroid cell proliferation. While the effects of vitamin D depletion in the pathogenesis of secondary hyperparathyroidism in elderly individuals or in the occurrence of parathyroid hyperplasia in patients with renal insufficiency are well established, the association between hypovitaminosis D and primary hyperparathyroidism (P-HPT) has only recently become appreciated. In different cohorts of patients with P-HPT, vitamin D deficiency has been recently associated with higher PTH levels, larger adenomas, and a more severe phenotype (including osteitis fibrosa cystica) as well as negative post-operative outcomes following parathyroidectomy. Despite current guidelines recommend measurement of serum 25OHD (25-hydroxy-cholecalciferol) in P-HPT and their repletion if the levels are <20 ng/ml, future well-designed trials of vitamin D supplementation in P-HPT patients with coexisting vitamin D deficiency are needed to evaluate the risk/benefit profile of this treatment.

Topics: 25-Hydroxyvitamin D 2; Adenoma; Bone and Bones; Female; Humans; Hyperparathyroidism, Primary; Parathyroid Hormone; Parathyroidectomy; Postmenopause; Vitamin D; Vitamin D Deficiency

Primary hyperparathyroidism is rare in children. Absence of specific symptoms and limited biochemical evaluation in children has led to lengthy delays in diagnosis with the potential for damage to the kidneys and skeleton.. The setting involved a private practice referral to a large tertiary care center.. Our patient is a 16-yr-old male presenting with gross hematuria, left flank pain, and right foot pain.. A biochemical evaluation revealed hypercalcemia and elevated parathyroid hormone levels. Renal ultrasonography demonstrated bilateral nephrolithiasis. Parathyroid ultrasonography and dual-phase technetium-99m sestamibi scintigraphy revealed a parathyroid adenoma in the left mid/lower anterior thyroid bed. A 4.5-g adenoma was removed at parathyroidectomy.. Bone mineral content and density performed by dual energy X-ray absorptiometry at the time of diagnosis and 1 yr after parathyroidectomy.. The main outcome measurement is a dramatic (24%-whole body and 49.9%-left hip) increase in bone mineral density during the 1-yr interval.. Delay in diagnosis of hyperparathyroidism is common in children, related to vague symptomatology and infrequent use of laboratory evaluations in children. Such delays lead to increased risk of osteoporotic fractures and kidney stones. This case illustrates the emergent need of diagnostic evaluation in children presenting with similar symptoms. We emphasize the importance of bone densitometry in children, which is not often considered as part of the standard evaluation in this age group. The remarkable increase in bone mineral density in the 1 yr after surgery attests to the plasticity of recovery of the growing skeleton.

Topics: 25-Hydroxyvitamin D 2; Absorptiometry, Photon; Adenoma; Adolescent; Bone and Bones; Bone Density; Humans; Hydronephrosis; Hyperparathyroidism, Primary; Kidney; Kidney Calculi; Lithotripsy; Male; Pain; Parathyroid Neoplasms; Parathyroidectomy; Radionuclide Imaging; Radiopharmaceuticals; Spine; Technetium Tc 99m Sestamibi; Trabecular Meshwork; Ultrasonography