Progressive pseudorheumatoid dysplasia: A rare cause of short stature

ABSTRACT Progressive pseudorheumatoid dysplasia (PPD) is a rare autosomal recessive skeletal dysplasia caused by WNT1-inducible signaling pathway protein 3 (WISP3) gene mutation, also called cellular communication network factor 6 (CCN6). It is often misdiagnosed as juvenile idiopathic arthritis (JIA). We report a 16-year 4-month-old male presenting with short stature associated with progressive joint enlargement, stiffness of small joints of both hands and feet and growth failure since 6 years of age. Patient also had difficulty in walking for last 4 years. Clinical, radiographic, and biochemical evaluations were suggestive of PPD, confirmed by whole exome sequencing revealing a pathogenic CCN6 mutation. Absence of inflammation differentiated PPD from JIA. Early diagnosis prevents unnecessary treatments. Supportive therapy, including nonsteroidal anti-inflammatory drugs and physiotherapy, remains the mainstay of management.