Bone Disease in Primary Hyperparathyroidism

Abstract

Bone disease in severe primary hyperparathyroidism (PHPT) is described classically as osteitis fibrosa cystica (OFC). Bone pain, skeletal deformities and pathological fractures are features of OFC. Bone mineral density is usually extremely low in OFC, but it is reversible after surgical cure. The signs and symptoms of severe bone disease include bone pain, pathologic fractures, proximal muscle weakness with hyperreflexia. Bone involvement is typically characterized as saltand-pepper appearance in the skull, bone erosions and bone resorption of the phalanges, brown tumors and cysts. In the radiography, diffuse demineralization is observed, along with pathological fractures, particularly in the long bones of the extremities. In severe, symptomatic PHPT, marked elevation of the serum calcium and PTH concentrations are seen and renal involvement is manifested by nephrolithiasis and nephrocalcinosis. A new technology, recently approved for clinical use in the United States and Europe, is likely to become more widely available because it is an adaptation of the lumbar spine DXA image. Trabecular bone score (TBS) is a gray-level textural analysis that provides an indirect index of trabecular microarchitecture. Newer technologies, such as high-resolution peripheral quantitative computed tomography (HR-pQCT), have provided further understanding of the microstructural skeletal features in PHPT. KeywordsHyperparathyroidism; osteitis fibrosa cystica; nephrocalcinosis Copyright© ABE&M todos os direitos reservadosCorrespondence to: Francisco Bandeira, Disciplina de Endocrinologia, Faculdade de Ciências Médicas, Universidade de Pernambuco, Av. Rui Barbosa, 1435, 52050-450 -Recife, PE, Brasil, fbandeira@gmail.com. Disclosures: Dr. Bandeira is a consultant for Servier and Sanofi and receives research support from Amgen. Dr. Bilezikian is a consultant for Amgen, Eli Lilly, Radius, NPS Pharmaceuticals, Merck, and GSK, and receives research support from NPS Pharmaceuticals and Amgen. Drs. Silva, Cusano, Cassibba, Almeida and Machado: no conflicts of interest reported. In a series of 124 patients from Recife, about ten years ago, 25% of patients had severe skeletal involvement and OFC (1). Similar data were found in the city of São Paulo (5). NIH Public AccessMore recently, however, in a recent epidemiological study from the same institution with 4207 patients evaluated, only 6.1% had OFC (6).The aim of this work is to review current more relevant data on bone involvement in the various forms of primary hyperparathyroidism. Clinical manifestationsThe signs and symptoms of severe bone disease include bone pain, pathologic fractures, proximal muscle weakness with hyperreflexia. Although these patients usually present with non-specific symptoms such as weakness, depression and constipation, the dominant picture occurs due to severe bone abnormalities (1). Bone involvement is typically characterized as salt-and-pepper appearance in the skull (Figure 1), bone erosions and bone resorption of the phalanges (Figure 2), brown tumor...

Bone Histomorphometry and Bone Quality in Primary Hyperparathyroidism

“…In doing so, the osteoclasts create long furrows in the interior of the trabecular plate (Figure 29.12). 12,37,77,78 This mechanism is compatible with Eriksen's finding of decreased erosion depth. 48,49 Under conditions of moderate PTH excess, the change in osteoclast behavior would result in a more tangential pattern of "sweeping erosion," quantitatively translated by more shallow erosion lacunae, thereby allowing the plates to remain connected, although they are thinner than normal.…”

“…37 Among histomorphometric studies performed over four decades ago, the classic studies of Jowsey, Meunier, Melsen, Mosekilde, and their colleagues contributed importantly to our present understanding of bone turnover in this disease. [38][39][40][41][42] More recent studies have confirmed the accelerated rate of bone remodeling in PHPT.…”

Targeted Transgenic Expression of an Osteoclastic Transmembrane Protein-tyrosine Phosphatase in Cells of Osteoclastic Lineage Increases Bone Resorption and Bone Loss in Male Young Adult Mice

“…The underlying mechanistic reason for the apparent uncoupling of bone formation to the increased bone resorption is unclear. Defective bone coupling has been implicated as a key contributing factor for bone loss in many metabolic bone diseases with excessive bone resorption, such as postmenopausal osteoporosis (28), hyperparathyroidism (29), hyperthyroidism (29), renal insufficiency (30), and osteodystrophies (31). It is conceivable that pathologic conditions with persistent activation of bone resorption (such as in the case of PTP-oc overexpression) could create a situation where a "disequilibrium" develops between resorption and the coupled bone formation.…”

Parathyroid Growth

“…63 However, increased bone turnover and increased rate of loss of cortical bone are non-specific, whereas osteitis fibrosa is a qualitatively different bone disorder that is specific to excess PTH secretion, 57 and its presence is both a logical and an unambiguous index of a particular degree of disease severity that has existed for several years. Regrettably, many observers have failed to appreciate this crucial distinction and have reported the presence or absence of "bone disease" without qualification.…”