Australian Doctor Australian Doctor 15th December 2017 | Page 15

PULL-OUT SECTION COMPLETE HOW TO TREAT QUIZZES ONLINE www.howtotreat.com.au INSIDE Epidemiology Pathophysiology Clinical features Diagnosis Management The future Case study THE AUTHOR ASSOCIATE PROFESSOR PAUL BIRD Conjoint Associate Professor at the University of NSW, Sydney. Psoriatic arthritis Background PSORIATIC arthritis is one of the spondyloarthropathies; a group of related conditions with common clinical features and an increased frequency of HLA B27. The shared clinical features include axial skel- eton involvement (sacroiliac joints and spine), peripheral joint involve- ment that is commonly asymmetric, oligoarticular, large joint, as well as enthesitis, tenosynovitis and extra- articular features, including uveitis. 1 Patients with psoriatic arthritis have varied clinical presentations and a diverse spectrum of disease. Some patients have mild symptoms requiring conservative therapy, but patients with moderate to severe disease experience considerable morbidity. In the past ten years, new approaches to the diagnosis and treatment of psoriatic arthritis have dramatically altered the outcome for this group of patients. Epidemiology PSORIATIC arthritis has existed since antiquity. Skeletal remains discovered in 1983 at a Byzantine monastery in Judea demonstrate visual and radiographic features consistent with the condition. 2 The prevalence of the disorder was previously underestimated but recent studies using new classification criteria indicate that it occurs in up to 30% of patients with psoriasis. 3 Psoriasis precedes joint manifestations in most cases (see fig- ures 1 and 2), but the severity of psoriasis does not correlate with onset of joint symptoms. In about 15% of cases, the onset of joint symptoms occurs simultaneously with psoriasis or precedes the skin disease. 4 The male to female ratio is 1:1 and can occur at any age. The peak period of disease onset is 30-50 years of age. cont’d next page www.australiandoctor.com.au Figure 1. Psoriatic arthritis of a digit. MRI index finger: psoriatic arthritis (mutilans form). Shown is a T2 weighted, fat-suppressed, sagittal image of the index finger in a patient with psoriatic arthritis (mutilans form). Focal increased signal (probable erosion) is seen at the base of the middle phalanx (long, thin arrow). There is synovitis at the proximal interphalangeal joint (long, thick arrow) plus increased signal in the overlying soft tissues indicating oedema (short, thick arrow). There is also diffuse bone oedema (short, thin arrows) involving the head of the proximal phalanx and extending distally down the shaft. Copyright © 2017 Australian Doctor All rights reserved. No part of this publication may be reproduced, distributed, or transmitted in any form or by any means without the prior written permission of the publisher. For permission requests, email: [email protected] 15 December 2017 | Australian Doctor | 15