Progressive pseudorheumatoid arthropathy of childhood

Progressive pseudorheumotoid dysplasia: A presentation of four cases with slow and rapid progression and effects of early rehabilitation program

Progressive pseudorheumotoid dysplasia (PPD) is a rare hereditary musculoskeletal disorder which is usually misdiagnosed due to its clinical resemblance to juvenile idiopathic arthritis. It has a high incidence in the Middle East, Gulf States, and countries of Mediterranean basin. Herein, we present four cases of PPD from Turkey (two siblings pair from the same kindred who are far paternal cousins) showing different disease courses. The progression of disease was particularly aggressive in the male sibling who suffered from severe scoliosis with more crippling joint disease. These four cases of PPD support the clinical heterogeneity and variable expressivity of PPD. In this article, we draw attention to the effects of patient education and early rehabilitation which helped to slow progression of range of motion loss.

Progressive pseudorheumatoid dysplasia: a rare childhood disease

Progressive pseudorheumatoid dysplasia (PPRD) is a genetic bone disorder characterised by the progressive degeneration of articular cartilage that leads to pain, stiffness and joint enlargement. As PPRD is a rare disease, available literature is mainly represented by single case reports and only a few larger case series. Our aim is to review the literature concerning clinical, laboratory and radiological features of PPRD. PPRD is due to a mutation in Wnt1-inducible signalling protein 3 (WISP3) gene, which encodes a signalling factor involved in cartilage homeostasis. The disease onset in childhood and skeletal changes progresses over time leading to significant disability. PPRD is a rare condition that should be suspected if a child develops symmetrical polyarticular involvement without systemic inflammation, knobbly interphalangeal joints of the hands, and gait abnormalities. A full skeletal survey, or at least a lateral radiograph of the spine, can direct towards a correct diagnosis that can be confirmed molecularly. More than 70 WISP3 mutations have so far been reported. Genetic testing should start with the study of genomic DNA extracted from blood leucocytes, but intronic mutations in WISP3 causing splicing aberrations can only be detected by analysing WISP3 mRNA, which can be extracted from cultured skin fibroblasts. A skin biopsy is, therefore, indicated in patients with typical PPRD findings and negative mutation screening of genomic DNA.

Progressive Pseudorheumatoid Dysplasia or JIA?

Progressive pseudorheumatoid dysplasia (PPD) or spondyloepiphyseal dysplasia tarda with progressive arthropathy (SEDT-PA) is a rare arthropathy of childhood involving the axial skeleton as well as small peripheral joints. A 10-year-old boy was referred by a general practitioner with pain and deformity in the fingers of hands and limping gait. There was no joint synovitis although the finger joints were bulky on examination with mild flexion deformity. Patient had exaggerated kyphosis and lumbar lordosis with pigeon chest and restricted hip joint movements. Anteroposterior X-rays of the hip joints revealed widened and flattened epiphyses of the femoral heads with narrow and irregular joint spaces. Hand X-rays revealed periarticular osteopenia, significant narrowing of the joint spaces of proximal interphalangeal, and distal interphalangeal joints, together with osseous enlargement of the basis of metacarpal bones and phalanges. Spinal X-rays revealed generalized platyspondyly and anterior beaking of vertebral bodies. There was a clear mega os trigonum in his feet images. All blood investigations were normal with no evidence of inflammation and thyroid hormone levels were normal. The diagnosis of PPD was favored by imaging studies and normal inflammatory markers and the patient was treated with physiotherapy, family counseling, and anti-inflammatory medications.

WISP3 mutational analysis in Indian patients diagnosed with progressive pseudorheumatoid dysplasia and report of a novel mutation at p.Y198

Objectives

To determine the pattern of mutations of the WISP3 gene in clinically identified progressive pseudorheumatoid dysplasia (PPD) in an Indian population.

Patients and Methods

A total of 15 patients with clinical features of PPD were enrolled in this study. Genomic DNA was isolated and polymerase chain reaction performed to amplify the WISP3 gene. Screening for mutations was done by conformation-sensitive gel electrophoresis, beginning with the fifth exon and subsequently proceeding to the remaining exons. Sanger sequencing was performed for both forward and reverse strands to confirm the mutations.

Results

In all, two of the 15 patients had compound heterozygous mutations: one a nonsense mutation c.156C>A (p.C52*) in exon 2, and the other a missense mutation c.677G>T (p.G226V) in exon 4. All others were homozygous, with three bearing a nonsense mutation c.156C>A (p.C52*) in exon 2, three a missense mutation c.233G>A (p.C78Y) in exon 2, five a missense mutation c.1010G>A (p.C337Y) in exon 5, one a nonsense mutation c.348C>A (p.Y116*) in exon 3, and one with a novel deletion mutation c.593_597delATAGA (p.Y198*) in exon 4.

Conclusion

We identified a novel mutation c.593_597delATAGA (p.Y198*) in the fourth exon of the WISP3 gene. We also confirmed c.1010G>A as one of the common mutations in an Indian population with progressive pseudorheumatoid dysplasia.

Cite this article: V. Madhuri, M. Santhanam, K. Rajagopal, L. K. Sugumar, V. Balaji. WISP3 mutational analysis in Indian patients diagnosed with progressive pseudorheumatoid dysplasia and report of a novel mutation at p.Y198* Bone Joint Res 2016;5:301–306. DOI: 10.1302/2046-3758.57.2000520.

Spondyloepiphyseal dysplasia tarda with progressive arthropathy complicated with paraplegia

Spondyloepiphyseal dysplasia tarda with progressive arthropathy is characterized by short stature resulting from platyspondylia and progressive arthropathy. This disorder may cause a predisposition to disk herniations, which may rarely lead to spastic paraplegia. We report a 21-yr-old male patient with spondyloepiphyseal dysplasia tarda with progressive arthropathy who developed spastic paraplegia because of spinal stenosis caused by thoracic disk herniations.

Progressive pseudorheumatoid dysplasia: Three cases in one family

Progressive pseudorheumatoid dysplasia is an inherited skeletal dysplasia with autosomal recessive transmission. Radiographs of the spine show abnormalities similar to those seen in spondyloepiphyseal dysplasia tarda. The clinical presentation, but not the imaging study findings, suggest juvenile idiopathic arthritis. We report 3 cases of progressive pseudorheumatoid dysplasia in the same family.

CASE-REPORTS

A 4-year-old girl had been receiving follow-up for 3 years for seronegative, polyarticular juvenile idiopathic arthritis progressing by flares and remissions. The disease was unresponsive to anti-inflammatory medications. Findings at admission included inflammatory joint pain, joint swelling, range-of-motion limitation, and joint deformities in the hands, wrists, ankles, and knees. The hips were normal. Normal values were found for the erythrocyte sedimentation rate and C-reactive protein level. Synovial fluid removed from one of the knees exhibited mechanical properties. Plain radiographs of the hands and forefeet showed no evidence of joint destruction. Bilateral hip dysplasia was noted on a radiograph of the pelvis. The diagnosis of juvenile idiopathic arthritis was reconsidered. A study of the family identified two similar cases, in a brother and paternal uncle. The brother, who was 14 years old, had similar manifestations without laboratory evidence of inflammation; radiographs disclosed dysplasia of the hips and metacarpophalangeal epiphyses. Manifestations in a paternal uncle consisted of spinal stiffness, thoracic kyphosis, and motion-range limitation at the hips; radiographs showed normal sacroiliac joints and bilateral hip dysplasia. A diagnosis of progressive pseudorheumatoid dysplasia with polyarticular involvement was given.

DISCUSSION

Progressive pseudorheumatoid dysplasia is an autosomal recessive disease characterized by abnormal cartilage homeostasis. It should be included among the differential diagnoses of juvenile idiopathic arthritis.