OP0080 OSTEOPOIKILOSIS IN PATIENT WITH ANKYLOSING SPONDYLITIS
Authors: V. Omelchenko, E. Letyagina, Y. Kurochkina, A. Akimova, M. Korolev
Journal: Annals of the Rheumatic Diseases (2021)

Background: Osteopoikilosis (OPK) – a rare congenital genetic-mediated benign sclerosing disease of skeleton. OPK is usually clinically asymptomatic and is most often an incidental finding during an X-ray study [1]. The lesions are from 2 to 10 mm and are located in the area of the ischial, pubic bones, metaepiphyseal regions of the tubular bones. The axial skeleton is usually not affected in OPK. As early described, OPK may be associated with inflammatory rheumatic diseases, such as rheumatoid arthritis, spondyloarthritis, reactive arthritis and scleroderma [2–4]. Ankylosing spondylitis is a chronic rheumatic disease from the group of spondyloarthritis with obligatory involvement of the sacroiliac joints and frequent involvement of entheses and peripheral joints. Although a significant mutual influence of OPK and AS has not been proven, their combination can lead to unreasonable over-examination in real clinical practice. Objectives: To present a clinical case of rare coexisting of osteopoikilosis and ankylosing spondylitis. Methods: Case report. The patient was treated and examined based on real clinical practice. Results: A 33-year-old man was admitted to our rheumatology department with a three-year history of inflammation pain in cervical region of spine and hip, knees and shoulder joints and long morning stiffness duration (up to 3 hours). AS was earlier verified based on modified New York criteria (1984) and Nonsteroidal anti-inflammatory drugs were prescribed promptly. On the outpatient basis he also received sulfasalazine and methotrexate due to arthritis and enthesitis. Nevertheless he had high disease activity (ESR 66 mm/h, CRP 77.5 mg/l, BASDAI = 7.5), severely limited range of motion in the cervical, thoracic and lumbar spine, arthritis, enthesitis when he entered in our clinic. He had been treated with secukinumab 150 mg for fourteen months and then he was switched to golimumab 50 mg per month because of lack of efficacy. Low disease activity has now been achieved. During the assessment of radiographs of the pelvic bones and spine, typical changes of the late stage of ankylosing spondylitis (syndesmophytes, stage 4 sacroiliitis) were revealed at the first visit in our clinic. At the same time, a number of phenomena were discovered that were not related to the course of the AS, which required expanding the differential diagnosis range. The tumor process and endocrine pathologies were excluded. OPK was diagnosed on the basis of characteristic changes in various parts of the skeleton, especially in phalanges, wrists and pelvis bones (fig.1). Figure 1. OPK spots in phalanges and wrists. Conclusion: We’ve reported rare case of AS and OPK coexisting in young patient. The identification of typical radiological phenomena and correct evaluation of clinical data may allow to avoid unnecessary expensive examinations. References: [1]Carpintero P. et al. Clinical features of ten cases of osteopoikilosis // Clin. Rheumatol. 2004. Vol. 23, № 6. P. 505–508. [2]Joseph R.O., Thomas J., Shenoy P. Osteopoikilosis and ankylosing spondylitis: Strange bedfellows: A case report // Int. J. Rheum. Dis. 2019. Vol. 22, № 6. P. 1162–1164. [3]Akgul O. et al. Osteopoikilosis and ankylosing spondylitis: A rare coexistence and good response to TNF blocker adalimumab // Int. J. Rheum. Dis. 2015. Vol. 18, № 3. P. 372–374. [4]Ruaro B. et al. Coexistence of osteopoikilosis with seronegative spondyloarthritis and Raynaud’s phenomenon: first case report with evaluation of the nailfold capillary bed and literature review. // Reumatismo. 2012. Vol. 64, № 5. P. 335–339. Disclosure of Interests: None declared