Osteogenesis imperfecta and rheumatoid arthritis: is there a link?

We present the cases of a mother and daughter with osteogenesis imperfecta, also diagnosed later with rheumatoid arthritis. In our patients finding and treating the over-imposed arthritis improved the joint pain initially attributed to osteogenesis imperfecta. Exploring joint inflammation in this setting could help ease the disease burden. PURPOSE: Osteogenesis imperfecta (OI) is a rare hereditary disease evolving with recurrent fractures upon minor trauma, blue sclerae, and hearing loss. Although inflammation was not generally considered a feature of the disease, systemic inflammation was recently reported in children with OI and in murine models of OI. METHOD: We present the cases of a mother and a daughter with OI, without a personal or family history of autoimmune diseases, who were also diagnosed with rheumatoid arthritis seropositive for anti-cyclic citrullinated peptide autoantibodies and rheumatoid factor. RESULTS: The genetic tests identified in both patients a deletion in COL1A1 gene (c.3399del, p.Ala1134Profs*105), not previously reported, not present in population databases, creating a premature translational stop signal in the COL1A1 gene in the collagen I major ligand binding region 3. In our patients finding and treating the over-imposed arthritis improved the joint pain initially attributed to OI. Possible pathogenic links between OI and RA are discussed. CONCLUSION: The prevalence of joint inflammation in OI is unknown and may be underestimated. As musculoskeletal involvement affects the quality of life in most OI patients, exploring this relation may help ease the disease burden.

Clinical and ultrasound findings in patients with calcium pyrophosphate dihydrate deposition disease.

AIM: To evaluate the presence and distribution of calcium pyrophosphate (CPP) deposits in joints commonly affected by CPP deposition (CPPD) disease (acromio-clavicular, gleno-humeral, wrists, hips, knees, ankles, and symphysis pubis joints) using ultrasound (US). MATERIAL AND METHODS: Thirty consecutive patients fulfilling McCarty diagnostic criteria for CPPD were consecutively enrolled in the study. The data registered using the US included the affected joints, the calcification site, and the pattern of calcification (thin hyperechoic bands, parallel to the surface of the hyaline cartilage, hyperechoic spots, and hyperechoic nodular or oval deposits). The presence of CPP crystals in knees was confirmed by polarized light microscopy examination of the synovial fluid and radiographs of the knees were performed in all patients. RESULTS: In 30 patients, 390 joints were scanned, (13 joints in every patient). The mean±standard deviation number of joints with US CPPD evidence per patient was 2.93±1.8 (range 1-9). The knee was the most common joint involved both clinically and using US examination. The second US pattern (with hyperechoic spots) was the most frequent. Fibrocartilage calcifications were more common than hyaline calcification. Using radiography as reference method, the sensitivity and specificity of US for diagnosis CPPD in knees was 79.31%, 95CI(66.65%-88.83%), and 14.29%, 95CI(1.78%-42.81%), respectively. CONCLUSIONS: The knee is the most frequent joint affected by CPPD. The second ultrasound pattern is the most common. CPPD affects the fibrocartilage to a greater extent than the hyaline cartilage.