Hyperparathyroidism pathogenesis

FIGURE 23-5. Pathogenesis of secondary hyperparathyroidism and renal osteodystrophy in patients with CKD. 

FIGURE 76-7. Pathogenesis of secondary hyperparathyroidism and renal osteodystrophy in patients with chronic kidney disease. These adaptations are lost as renal failure progresses. (Ca, calcium, P04 phosphate PTH, parathyroid hormone.)... 

The pathogenesis of hypertension in patients with CKD is multifactorial and includes fluid retention, increased sympathetic activity, an endogenous digitalis-like substance, elevated levels of endothelin-1, erythropoietin use, hyperparathyroidism, and structural arterial changes. 

Pruritus is a common problem in patients with ESRD. The pathogenesis is poorly understood but has been attributed to inadequate dialysis, skin dryness, secondary hyperparathyroidism, increased concentrations of vitamin A and histamine, and increased sensitivity to histamine. 

Renal osteodystrophy is a complex disorder with several pathogenic factors. Histological evidence of bone disease is common in early renal failure and deficits in calcitriol synthesis seems to be an important factor in the pathogenesis of secondary hyperparathyroidism in early CRF. The most common component is osteitis fibrosa manifested as subperiosteal resorption of bone. This is due to decreased excretion as well as increased secretion of parathyroid hormone. In CRF small increments of serum phosphorus cause small decreases in serum calcium. 

Racke F, McElenry C, Wentworth D. Lithium-induced alterations in parathyroid cell function insight into the pathogenesis of lithium-associated hyperparathyroidism. Am J Surg 1994 168(5) 462-465. 

Slatopolslcy E, Caglar S, Pennell JP, Taggart DD, Canterbury JM, Reiss E, et al. On the pathogenesis of hyperparathyroidism in chronic experimental renal insufficiency in the dog. J Clin Invest 1971 50 492-9. 

Patients with CKD are at increased risk of cardiovascular disease, independent of the etiology of their kidney disease. While a clearly unique pathogenesis of cardiovascular disease specific to CKD has not been identified, it is known that manifestations of kidney disease are contributory. Risk factors for cardiovascular disease in this population include hemodynamic and metabolic abnormalities, as well as hypertension, dyslipidemia, elevated homocysteine levels, anemia, hyperparathyroidism, malnutrition, and oxidative stress. Hypertension induced by volume expansion and increased systemic vascular resistance increases myocardial work and contributes to development of left ventricular hypertrophy (LVH). Hyperlipidemia may enhance atherogenesis, while some uremic toxins can decrease myocardial contractflity. In addition, uremic toxins can induce pericarditis, a potentially fatal complication. Currently, measures to screen this high-risk population for cardiovascular risk factors are not routine. ... 

Slatopolsky E, Brown A, Dusso A. Pathogenesis of secondary hyperparathyroidism. Kidney Int Suppl 1999 73 S14-S19. 

Martinez 1, ct al. A deficit of calcitriol synthesis may not be the initial factor in the pathogenesis of secondary hyperparathyroidism. Nephrol Dial Transplant 1996 l(Suppl 3) 22-28. 

Arnold A, Shattuck TM, Mallya SM, Krebs LJ, Costa J, Gallagher J, Wild Y, Saucier K (2002) Molecular pathogenesis of primary hyperparathyroidism. J Bone Miner Res 17 (Suppl 2) N30-36... 

Calciphylaxis is a rare life-threatening disorder characterized hy progressive vascular calcification and ischemic tissue loss in patients with end-stage renal disease (Wood et al. 1997 Hafner et al. 1998 Karpman et al. 2003 Guvel et al. 2004). The pathogenesis is poorly understood it is likely the result of a multiplicity of co-morbid factors or events. Disorders that are most often implicated include chronic renal failure, hypercalcemia, hyperphosphatemia, an elevated calcium-phosphate product and secondary hyperparathyroidism. Very rare cases of calciphylaxis not associated with chronic renal failure have been reported with breast cancer, hyperparathyroidism and alcoholic cirrhosis. 

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