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Several diseases can result in defective mineralization of bone in children, including the following:
Rickets
Nutritional rickets
Congenital rickets
Rickets of prematurity
Genetic rickets
Neoplastic rickets
Hypophosphatemic rickets
Drug-induced rickets
Renal causes - Renal osteodystrophy, Fanconi syndrome
Tumor-induced osteomalacia
Other causes
Hypophosphatasia
McCune-Albright syndrome
Osteogenesis imperfecta with mineralization defect (syndrome resembling osteogenesis imperfecta)
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http://www.wheelessonline.com/ortho/hypophosphatemic_vitamin_d_resista ...
Wheeless' Textbook of Orthopaedics
Discussion:
- this is the most frequently encountered form of rickets and consists of a genetic or
acquired fault in the handling of phosphate in the proximal tubule;
- patholophysiology:
- decreased reabsorpion of phosphate by the renal tubule (causing hypophosphatemia) (otherwise the renal function is
normal, ie BUN and Cr are normal);
- decreased absorption of calcium and phosphorous from the GI tract;
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http://www.wheelessonline.com/ortho/rickets
Wheeless' Textbook of Orthopaedics
See:
- Osteomalacia:
- Vit D Abnormalities:
- Discussion:
- rickets is an osteomalacic syndrome in which there is an inability to mineralize chondroid and osteoid;
- lack of available calcium or phosphorus (or both) for mineralization of newly formed osteoid;
- osseous changes in both adults and children reflect the fact that either ionized calcium
or phosphate, or both, is insufficient in concentration to mineralize the skeleton fully;
- there is less mineralized bone per unit volume of bone;
- osseous changes in the rapidly growing skeleton of a young child w/ rickets may result in bowing
deformities due to the decreased resistance of the skeleton to bending and shearing moments;
- as consequence, stress frxs w/ resultant deformities occur;
- note that the classic changes of rickets will typically occur in children younger than 6-7 years of age;
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