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08:42
Skeletal Phenotype Analysis of a Conditional Stat3 Deletion Mouse Model
Published on: July 3, 2020
Hypophosphatemic rickets in opsismodysplasia
Martha Dechert Zeger1, Deanna Adkins, Lynn A Fordham
1Pediatrics, Thomas Jefferson University, Philadelphia, PA, USA.
Journal of Pediatric Endocrinology & Metabolism : JPEM
|February 24, 2007
Summary
Opsismodysplasia, a rare skeletal dysplasia, is now linked to hypophosphatemic rickets and elevated FGF23. Early phosphorus screening may reveal a treatable aspect of this condition.
Area of Science:
- Skeletal Dysplasias
- Pediatric Endocrinology
- Genetics
Background:
- Opsismodysplasia is a rare spondylo(epi)chondrodysplasia with delayed skeletal maturation.
- Metaphyseal irregularities are known, but renal phosphate wasting and rickets were not previously reported.
Observation:
- Two girls with opsismodysplasia presented with hypophosphatemia by age three.
- Both patients exhibited hypophosphatemia, decreased tubular reabsorption of phosphate (TRP), and rickets.
Findings:
- Treatment with oral phosphorus and calcitriol improved metaphyseal mineralization.
- Serum phosphate remained low, and renal phosphate wasting persisted.
- Genetic analysis for PHEX and FGF23 was negative, but FGF23 levels were significantly elevated in one patient.
Implications:
- This study establishes an association between opsismodysplasia, hypophosphatemic rickets, and elevated FGF23.
- Screening for phosphorus levels in opsismodysplasia may identify a treatable component.
- Further research into FGF23's role in opsismodysplasia is warranted.
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