Genotype-phenotype correlations in a case of fibrodysplasia ossificans progressiva: a case report

Saswati Mukhopadhyay

doi:10.18203/issn.2455-4510.IntJResOrthop20263952

Authors

Saswati Mukhopadhyay Department of Genomics, Apollo Multispeciality Hospital, Kolkata, West Bengal, India

DOI:

https://doi.org/10.18203/issn.2455-4510.IntJResOrthop20263952

Keywords:

Heterotopic ossification, Hallux valgus malformations, Thoracic insufficiency syndrome

Abstract

Fibrodysplasia ossificans progressiva (FOP) is an ultrarare autosomal dominant genetic disorder. Most of the musculoskeletal characteristics of FOP are related to dysregulated chondrogenesis. Activating mutations of activin receptor A type I (ACVR1), a bone morphogenetic protein (BMP) type I receptor, are responsible for the skeletal and nonskeletal features. Characteristic features include congenital bilateral hallux valgus malformation and early-onset heterotopic ossification occurring spontaneously or, more frequently, precipitated by trauma. As disease progresses, thoracic insufficiency syndrome appears, with respiratory distress, pneumonia and right-sided heart failure. Diagnosis is confirmed by the identification of a heterozygous pathogenic variant in the ACVR1/ALK2 gene. Avoiding unnecessary surgical procedures, prescribing prophylactic corticosteroids, preventing falls represent essential interventions for care management.

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