The first presentation of a case of nail-patella syndrome newly diagnosed at the onset of rheumatoid arthritis: a case report

• Published in: BMC musculoskeletal disorders Vol. 25; no. 1; p. 139
• Main Authors: Matsumoto, Kazuya, Matsumoto, Yoshinori, Nawachi, Shoichi, Asano, Yosuke, Katayama, Yu, Miyawaki, Yoshia, Katsuyama, Takayuki, Katsuyama, Eri, Nasu, Yoshihisa, Sada, Ken-Ei, Wada, Jun
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 14.02.2024; BioMed Central; BMC
• Subjects: Abnormalities; Aged; Antibodies; Arthralgia; Arthritis, Rheumatoid - complications; Arthritis, Rheumatoid - diagnosis; Biopsy; Bones; C-reactive protein; Case Report; Case reports; Case studies; Diagnosis; Dislocation; Dysplasia; Elbow; Genetic disorders; Glaucoma; Glomerular filtration rate; Hereditary diseases; Hip dislocation; Humans; Hyperplasia; Hypoplasia; Iliac horn; Janus kinase; Joint diseases; Joint dislocation; Kinases; Magnetic Resonance Imaging; Male; Methotrexate; Mutation; Nail-patella syndrome; Nail-Patella Syndrome - diagnosis; Nail-Patella Syndrome - diagnostic imaging; Neutrophils; Patellar Dislocation - complications; Patients; Peptides; Radiography; Remission; Rheumatoid arthritis; Rheumatoid factor; Synovitis; Transcription factors; Japan; Iliac horn; Case report; Nail-patella syndrome; Rheumatoid arthritis; Joint dislocation
• ISSN: 1471-2474; 1471-2474
• DOI: 10.1186/s12891-024-07242-2

Nail-patella syndrome (NPS) is a rare autosomal dominant disorder that is characterized by dysplasia of the nails, hypoplasia and/or dislocation of the patella and the presence of iliac horns. Using the CARE guidelines, we present the first reported case of NPS that was newly diagnosed at the onset of rheumatoid arthritis (RA). A 74-year-old man was admitted to our hospital due to an 8-month history of arthralgia in bilateral wrists, elbows and fingers. He had a past history of glaucoma and left patella dislocation that had been operatively recentered at the age of 15 years. Laboratory data showed elevated levels of serum C-reactive protein and rheumatoid factor and an elevated titer of anti-SS-A antibodies, while estimated glomerular filtration rate (eGFR), titers of other antibodies and the results of a urinary test were normal. An X-ray showed deformity of bilateral radial heads and the right elbow, and magnetic resonance imaging (MRI) of his hands showed synovitis and erosion in the multiple swollen joints of the wrists and fingers. In addition to these typical features of RA, he had bilateral thumb nail dysplasia with mild hypoplasia of bilateral patellae and iliac horns as shown by the X-ray. He was diagnosed as having autosomal dominant disorder NPS co-existing with RA and he was treated with methotrexate in combination with an oral Janus kinase (JAK) inhibitor, leading to induction of remission. We have presented a rare case of NPS that was newly diagnosed at the onset of RA. Clinical and radiographic findings of NPS are highlighted in this case report for diagnosing NPS on the basis of typical manifestations.