Progressive Pseudo-Rheumatoid Dysplasia a Rare Genetic Musculoskeletal Condition Causing Crippling Disability in a Young Boy- a Case Report

Abstract

Progressive pseudo-rheumatoid dysplasia (PPRD) is an uncommon genetic condition inherited in an autosomal recessive mode caused by a mutation in the WNT1-inducible signaling pathway protein 3 (WISP3) located on chromosome 6q21. In this condition, the articular cartilage gradually deteriorates, causing severe discomfort, stiffness, and joint deformities with a relatively high prevalence in Middle Eastern countries. Camptodactyly and platyspondyly are the standard features found in this condition. We present a very young boy diagnosed with bilateral hip dysplasia during early childhood and developing increasing pain, stiffness and deformities in the hands, elbow, hips, knee, and ankle. The diagnosis was suspected based on characteristic clinical and radiological features. The diagnosis was confirmed by genetic testing and the absence of elevated serum inflammatory markers. He was born out of a consanguineous marriage, and his parents were unaffected. They are three siblings; his elder sister has a milder condition, while his elder brother is unaffected. There were no adverse events during pregnancy. Birth weight was within normal limits, met all developmental milestones on time, and had no significant past medical history. Compounded by hip dysplasia, he developed a severe disability and had to undergo joint replacement surgery at a very young age. PPRD should be suspected in children from Middle Eastern countries of 3-8 years of age who present with multiple joint pain and stiffness and are born out of inbred family marriages. Diagnosis can be suspected by the characteristic clinical and radiological features coupled with the absence of raised serum inflammatory markers and confirmed by genetic testing. Genetic counseling and pre-marriage testing are of valuable help in prevention.