Opsismodysplasia: Phosphate Wasting Osteodystrophy Responds to Bisphosphonate Therapy

Ansab Khwaja,Kathryn Ness,Klane K White,Viviana Bompadre,Shawn E Parnell

doi:10.3389/fped.2015.00048

Ansab Khwaja, Kathryn Ness + Show 3 more

Open Access

https://doi.org/10.3389/fped.2015.00048

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Abstract

We present two siblings affected with opsismodysplasia (OPS), a rare skeletal dysplasia caused by mutations in the inositol polyphosphate phosphatase-like 1 gene. The skeletal findings include short stature with postnatal onset micromelia, marked platyspondyly, squared metacarpals, delayed skeletal ossification, metaphyseal cupping, and postnatal micromelia. Respiratory compromise, delayed ambulation, and progressive lower extremity deformities are described. The severity of findings is variable. Renal phosphate wasting is associated with severe bone demineralization and a more severe phenotype. This report represents the first described cases of opsismodysplasia treated with intravenous bisphosphonate (pamidronate). Surgical management for lower extremity deformities associated with OPS is also reviewed.Level of Evidence: IV Case series

Highlights

We present two siblings affected with opsismodysplasia (OPS), a rare skeletal dysplasia caused by mutations in the inositol polyphosphate phosphatase-like 1 gene
Opsismodysplasia (OPS) is a rare autosomal recessive skeletal dysplasia associated with delayed bone maturation and micromelia [1, 2]
Both patients’ clinical presentations are largely in accordance with the literature. Their facial features were consistent with those described in OPS, including a prominent brow, relative macrocephaly with a large anterior fontanel, depressed nasal bridge, anteverted nose, and a long philtrum [4,5,6]

Summary

Introduction

Opsismodysplasia (OPS) is a rare autosomal recessive skeletal dysplasia associated with delayed bone maturation and micromelia [1, 2]. Opsismodysplasia can be associated with renal phosphate wasting [12]. The two patients in this case report were diagnosed with opsismodysplasia based on their clinical and radiographic findings. Their diagnosis was confirmed on molecular analysis. The older sibling had findings of renal phosphate wasting. Both were treated with a bisphosphonate (pamidronate). This case series adds to the current literature on this rare condition with a clinical description of our two patients, documenting their surgical management as well as their response to bisphosphonate therapy. Our study is IRB approved (12259) and the patient’s family gave full consent

Bone disease in opsismodysplasia

Findings

Discussion

Summary