vitamin D-resistant rickets

rickets /rick·ets/ (rik´ets) a condition due to vitamin D deficiency, especially in infancy and childhood, with disturbance of normal ossification, marked by bending and distortion of the bones, nodular enlargements on the ends and sides of the bones, delayed closure of the fontanelles, muscle pain, and sweating of the head.

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adult rickets  osteomalacia.

familial hypophosphatemic rickets  any of several inherited disorders of proximal renal tubule function causing phosphate loss, hypophosphatemia, and skeletal deformities, including rickets and osteomalacia.

fetal rickets  achondroplasia.

hereditary hypophosphatemic rickets with hypercalciuria  a form of familial hypophosphatemic rickets; hypophosphatemia is accompanied by elevated serum 1,25-dihydroxyvitamin D, increased intestinal absorption of calcium and phosphate, and hypercalciuria.

hypophosphatemic rickets  any of a group of disorders characterized by rickets associated with hypophosphatemia, resulting from dietary phosphorus deficiency or due to defects in renal tubular function; skeletal deformities are present but hypocalcemia, myopathy, and tetany are absent and serum parathyroid hormone is normal.

oncogenous rickets  oncogenous osteomalacia occurring in children.

pseudovitamin D–deficiency rickets  vitamin D, sometimes specifically the type I form.

refractory rickets  vitamin D

vitamin D–dependent rickets  either of two (types I and II) inherited disorders characterized by myopathy, hypocalcemia, moderate hypophosphatemia, secondary hyperparathyroidism, and subnormal serum concentrations of 1,25-dihydroxyvitamin D; type I can be overcome by high doses of vitamin D, but type II cannot.

vitamin D–resistant rickets 

1. X-linked hypophosphatemia.

2. any of a group of disorders characterized by rickets but not responding to high doses of vitamin D; most are forms of familial hypophosphatemic rickets.

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vitamin D-resistant rickets

n.

An inherited form of rickets characterized by high concentrations of phosphate in the blood due to defective renal tubular reabsorption of phosphate and subnormal absorption of dietary calcium. Also called X-linked hypophosphatemic osteomalacia.

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vitamin D-resistant rickets,

a genetic disease clinically similar to rickets but resistant to treatment with large doses of vitamin D. It is caused by a congenital defect in renal tubular resorption of phosphate and usually occurs in men. See also rickets.

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rickets

a disease of young growing animals caused by a nutritional deficiency of phosphorus or vitamin D. There is a failure of calcification of osteoid and cartilage of the bones which become bowed and a persistence with enlargement of the epiphyses so that the joints appear swollen. The animals are lame and dentition is delayed. Radiological examination shows a wider and thicker growth plate.

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adult rickets

osteomalacia; a rickets-like disease affecting adults.

fetal rickets

see achondroplasia.

hypervitaminosis D rickets

deposition of large amounts of osteoid matrix in the metaphyses with a delay in its mineralization occurs in feeding excessive amounts of vitamin D.

inherited rickets

affected piglets are normal at birth but develop rickets indistinguishable from classical rickets. There is a defect in calcium absorption.

renal rickets

see renal secondary hyperparathyroidism.

vitamin D-resistant rickets

a condition almost indistinguishable from ordinary rickets clinically but resistant to unusually large doses of vitamin D; it is often familial but may occur sporadically. In hypophosphatemic vitamin D-resistant rickets, hypophosphatemia is the main characteristic, while in hypocalcemic vitamin D-resistant rickets, the serum concentration of phosphate is within normal limits or nearly so, and the concentration of calcium is abnormally low.