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• Bone Disorders in Children
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Congenital hypophosphatasia is absence or low levels of serum alkaline phosphatase due to mutations in the gene encoding tissue nonspecific alkaline phosphatase.

Because serum alkaline phosphatase is absent or decreased, Ca⁺⁺ is not diffusely deposited in bones, causing low bone density and hypercalcemia. Vomiting, inability to gain weight, and enlargement of the epiphyses (similar to that in rickets) usually occur. Patients who survive infancy have bony deformities and short stature, but mental development is normal. No treatment is effective, but infusions of alkaline phosphatase and bone marrow transplantation have limited roles. NSAIDs reduce bone pain.

Last full review/revision February 2008 by Frank Pessler, MD, PhD; David D. Sherry, MD

Content last modified February 2008