Description
The British and European recommendations for managing PMR recommend specialist referral in the presence of atypical clinical features and failure to respond to glucocorticoids [1, 2]. Getting It Right First Time (GIRFT) is an initiative to harmonize practice and learn from examples of best practice. The GIRFT report for Rheumatology [3] mirrors this ethos in recommending that PMR should in general be cared for in primary and community settings. with the exception of complex cases and individuals refractory to treatment. It also states that PMR is commonly straightforward to diagnose.
Since its earliest descriptions PMR has remained a clinical diagnosis, based on satisfaction of several inclusion and exclusion criteria. The combination of common clinical manifestations, lack of a diagnostic test and symptomatic responsiveness to glucocorticoids can lead to significant misdiagnosis as well as unnecessary glucocorticoid exposure. PMR has been diagnosed mistakenly in individuals with lung cancer, rheumatoid arthritis, giant cell arteritis, Takayasu arteritis, myeloma and axial spondyloarthritis. Many other autoimmune, infectious, endocrine, and neoplastic conditions can present with similar symptoms and careful exclusion of these is needed. Slowly evolving clinical features mean that even in the strictest 'PMR cohorts, diagnostic revision is necessary (7% in the classification criteria validation cohort) [4]. Assessing the response to glucocorticoids as a diagnostic test can be problematic. Conditions mimicking PMR will often respond to glucocorticoids, and conversely up to 30% of individuals with PMR may not [4]. Therefore, there are risks of masking other emerging diagnoses and of inappropriately labelling non-responders as not having PMR.
ISBN: RHEUMATOLOGY
