AB1151 APPLICATION OF ULTRASOUND TO DISTINGUISHING PMR FROM POLYARTHRALGIA

Abstract

Background Japan is the world’s most aged country. The number of patients with polymyalgia rheumatica (PMR) is expected to increase more. Classification criteria including ultrasound findings were published in 2012, but the ability to differentiate PMR from rheumatoid arthritis (RA) was not significant. We will clarify whether recently reported ultrasound findings (1, 2) which could be characteristic in PMR are helpful for distinguishing from other diseases and treatment outcome in suspected PMR patients. Objectives Patients who were clinically suspected of PMR and underwent ultrasound examination from March 2015 to July 2018. Methods Recorded ultrasound images were retrospectively interpreted by the ultrasound expert, who was blind for clinical information. They were classified into three groups of PMR, RA, others/no inflammation. Initial dose of glucocorticoid (GC), therapeutic response, presence or absence of relapse, and concomitant medications were collected and compared among the 3 groups. Cases in which steroids had already been used before ultrasound examination were excluded from the analysis. Results The number of subjects was 81, and the number of ultrasound examination was 88. The ultrasound expert classified 29 PMR, 20 RA, 3 other/no inflammation. 18.5% (15/81) of the subjects were improved with no GC and relapse. The average prednisolone (PSL) dose was 15.3 mg in the PMR group, and 9.7 mg in the RA group. Concomitant medications were introduced in 31% (9/29) of PMR group, in 65% (13/20) of RA group. Conclusion Ultrasound is useful for distinguishing PMR from seronegative RA and other arthralgia. These findings showed that ultrasound is useful for the proper use of GC and concomitant medications.