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Hyperparathyroidism and chronic kidney disease Part 1. Features of pathogenesis, clinical manifestations, diagnostic strategy Lecture

https://doi.org/10.28996/2618-9801-2023-1-36-56

Abstract

Secondary hyperparathyroidism (HPT) in patients with chronic kidney disease (CKD) is part of the syndrome of mineral-bone disorders associated with CKD (MBD-CKD), which is a systemic disorder of mineral and bone metabolism. The development of the disease is closely associated with the loss of renal functions, leading to complex disorders in the metabolism of calcium, phosphorus, vitamin D, excessive secretion of fibroblast growth factor 23 (FGF23), and a decrease in renal expression of its membrane co-receptor αKlotho. All these disorders, as well as an altered skeletal response to the action of PTH, stimulate the synthesis and secretion of PTH in the PTG, followed by their diffuse, diffuse-nodular hyperplasia and a progressive decrease in the expression receptors on the surface of the gland. There is new information about the molecular mechanism of αKlotho/FGF23 and the Wnt/β-catenin signaling, which may contribute to the development of CKD-associated HPT. Secondary HPT is a common complication of CKD, which significantly impairs the quality of life of patients, complicates the implementation of kidney transplantation, leads to repeated hospitalizations, and increases mortality. In the Russian dialysis population, secondary HPT is detected in 54.8% and 28.6% of patients, respectively, with diagnostic criteria PTH >300 pg/ml and PTH >600 pg/ml. The disease has a systemic character and is manifested primarily by musculoskeletal and cardiovascular pathology and other extraskeletal disorders. The diagnosis of secondary HPT is based on the simultaneous assessment of the main biochemical markers of the disease - PTH, calcium, phosphorus, and alkaline phosphatase, studied over time, and the identification of trends in these markers. The diagnostic serum PTH level for secondary HPT in non-dialysis CKD remains unknown, in dialysis patients more than 4-6; in some cases, more than 9 upper limits of the reference interval are recommended. A variety of instrumental methods is used for detecting bone and cardiovascular pathology: plain radiography, dual-energy x-ray absorptiometry, variants of computed and magnetic resonance imaging, bone biopsy, and ultrasound. PTG visualization is carried out by ultrasound, computed tomography, 99mTc-sestamibi scintigraphy photon emission computed tomography; it is indicated for patients with severe HPT requiring surgical treatment.

About the Author

O. N. Vetchinnikova
M.F. Vladimirsky Moscow Regional Clinical and Research Institute (MONIKI)
Russian Federation


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Vetchinnikova O.N. Hyperparathyroidism and chronic kidney disease Part 1. Features of pathogenesis, clinical manifestations, diagnostic strategy Lecture. Nephrology and Dialysis. 2023;25(1):36-56. (In Russ.) https://doi.org/10.28996/2618-9801-2023-1-36-56

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