Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029463 (osteosarcoma)
 16,637 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Autosomal dominant hypocalcemia (ADH) is an inherited form of hypoparathyroidism caused by activating mutations in the calcium-sensing receptor (CaR). Treatment with PTH(1-34) may be superior to conventional therapy but is contraindicated in children, and long-term effects on the skeleton are unknown. The patient is a 20-yr-old female with ADH treated with PTH continuously since 6 yr and 2 mo of age. A bone biopsy was obtained for histomorphometry and quantitative backscattered electron imaging (qBEI). Her data were compared with one age-, sex-, and length of hypoparathyroidism-matched control not on PTH and two sex-matched ADH controls before and after 1 yr of PTH. The patient's growth was normal. Hypercalciuria and hypermagnesuria persisted despite normal or subnormal serum calcium and magnesium levels. Nephrocalcinosis, without evidence of impaired renal function, developed by 19 yr of age. Cancellous bone volume was dramatically elevated in the patient and in ADH controls after 1 yr of PTH. BMD distribution (BMDD) by qBEI of the patient and ADH controls was strikingly shifted toward lower mineralization compared with the non-ADH control. Moreover, the ADH controls exhibited a further reduction in mineralization after 1 yr of PTH. These findings imply a role for CaR in bone matrix mineralization. There were no fractures or osteosarcoma. In conclusion, long-term PTH replacement in a child with ADH was not unsafe, increased bone mass without negatively impacting mineralization, and improved serum mineral control but did not prevent nephrocalcinosis. Additionally, this may be the first evidence of a role for CaR in human bone.
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PMID:PTH(1-34) replacement therapy in a child with hypoparathyroidism caused by a sporadic calcium receptor mutation. 1906 86

The conventional management of hypoparathyroidism in children involves the use of calcium and vitamin D analogs. This therapy effec-tively increases the serum calcium levels but worsens hypercalciuria and its consequences such as nephrocalcinosis and renal insuffi-ciency. Although replacement with the missing parathyroid hormone (PTH) is ideal and available for more than 2 decades, the reported concerns of osteosarcoma prohibited its use in children with open epiphyses. Nevertheless, the data accumulated over the past several years suggests that the fears of bone malignancies were probably overstated. With an aim to review the available data on recombinant PTH (rhPTH) use, we performed a literature search using international databases and identified 15 studies involving approximately 70 children with hypoparathyroidism due to various etiologies who received rhPTH1-34 for durations between 1 day and 13.5 years. All the studies appear to indicate that rhPTH1-34 therapy is an effective short and long-term strategy for treatment of hypoparathyroidism with better metabolic control, lesser effects on renal function and improved quality of life as compared to conventional therapy. A more significant conclusion is the safety of long-term use of rhPTH1-34 with no observed adverse skeletal effects so far. However, all studies mention the importance of a continued surveillance for adverse effects in the treated patients. This narrative review discusses the experi-ence of rhPTH1-34 use exclusively in children.
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PMID:Recombinant parathyroid hormone for hypoparathyroidism in children: a narrative review. 3227 Sep 74