OFC occurs in approximately 50% of patients with ESRD. ESRD occurs when the kidneys fail to produce calcitriol, a form of vitamin D, which assists in the absorption of calcium into the bones. When calcitriol levels decrease, parathyroid hormone levels increase, halting the storage of calcium, and instead triggering its removal from the bones. The concept of renal osteodystrophy is currently included into the broader term chronic kidney disease-mineral and bone disorder (CKD-MBD). Fluoride intoxicationOFC was noticed in the early years of community fluoridation to be at higher risk when water supplies were fluoridated. Indeed, death rates which in some cases were gruesomely dramatic during dialysis quickly brought attention to the fact that fluoride in water during dialysis was a health hazard. Modern dialysis takes pains to de-fluoridate water in order to minimize bone disease including OFC. The 2006 National Research Council confirmed kidney patients are a sub-population particularly susceptible to ill effects from fluoride exposure which manifest in bones.Fanconi syndrome: decrease amino acids, phosphate, glucose, bicarbonate and potassium salts. Pathophysiology
The effects of OFC on bone are largely dependent on the duration of the disease and the level of parathyroid hormone (PTH) produced. PTH is responsible for maintaining a homeostatic calcium concentration in the blood. It activates the parathyroid-hormone related protein receptor located on osteoclasts and osteocytes, both of which are responsible for the breakdown and maintaining of bone. Abnormalities affecting the parathyroid glands cause a surplus of PTH, which, in turn, increases the activity and frequency of osteoclasts and osteocytes.
The post-surgical survival rate hovers around seven years, while patients who do not undergo surgery have a survival rate of around five years. Epidemiology
Osteitis fibrosa cystica has long been a rare disease. Today, it appears in only 2% of individuals diagnosed with primary hyperparathyroidism, which accounts for 90% of instances of the disease. Primary hyperparathyroidism is three times as common in individuals with diabetes mellitus.The hospitalization rate for hyperparathyroidism in the United States in 1999 was 8.0 out of 100,000. The disease has a definite tendency to affect younger individuals, typically appearing before the age of 40, with a study in 1922 reporting that 70% of cases display symptoms before the age of 20, and 85% before 35. Primary hyperparathyroidism, as well as OFC, is more common in Asiatic countries. Before treatment for hyperparathyroidism improved in the 1950s, half of those diagnosed with hyperparathyroidism saw it progress into OFC.Rates of OFC increase alongside cases of unchecked primary hyperparathyroidism. In developing countries, such as India, rates of disease as well as case reports often mirror those published in past decades in the developed world.The other 10% of cases are primarily caused by primary hyperplasia, or an increase of the number of cells. Parathyroid carcinoma accounts for less than 1% of all cases, occurring most frequently in individuals around 50 years of age (in stark contrast to OFC as a result of primary hyperparathyroidism) and showing no gender preference. Approximately 95% of hyperparathyroidism caused by genetic factors is attributed to MEN type 1.