Provisional diagnostic criteria for polymyalgia rheumatica: Moving beyond clinical intuition?

Abstract

In 1964, US Supreme Court Justice Potter Stewart, a master of words, when trying to define hardcore pornography admitted, ‘I could never succeed in intelligibly doing so, but I know it when I see it…’. Polymyalgia rheumatica (PMR) has been in that sense the pornography of rheumatic diseases—a difficult to define syndrome of inflammatory pain and stiffness in older people, but one commonly encountered in practice, and not commonly missed by experienced clinicians. The response to low doses of corticosteroids is often rapid, dramatic, and has been used by many clinicians as a feature that helps define the disease. No single clinical finding or laboratory abnormality is unique to this disorder, and although some aspects of cytokine abnormalities and histopathological findings in this disorder are understood, there is no single identifiable aetiopathogenesis. The rather recent history of PMR is one of many names and definitions, reflecting this uncertainty about the pathology and pathogenesis.1 In this issue of Annals of the Rheumatic Diseases , Dasgupta and colleagues2 report provisional classification criteria for PMR. In a study jointly sponsored by the European League Against Rheumatism and the American College of Rheumatology the authors propose a set of ‘provisional’ classification criteria. These emerged as the result of a multiphase effort in which they initially developed candidate criteria through a systemic literature review, then a consensus process and wider survey. These criteria were then assessed by experts, and those that emerged as most widely agreed upon were reviewed by both rheumatologists and non-rheumatologists in a wider survey generating a number of criteria most widely accepted. They then evaluated the performance of these proposed criteria in a 6-month prospective cohort study of 125 patients with new-onset PMR and 169 non-PMR control patients whose clinical presentation included features that can mimic PMR. They assessed …