Fibromyalgia

FM has long been a controversial entity among clinicians and raised a diagnostic challenge. The following chapter reviews the progression of the FM criteria. The initial ACR 1990 criteria focused on the determination of chronic widespread pain and included both primary and secondary FM. Its main limitations were the difficulty of applying to clinical practice and exclusion of associated symptoms from the diagnosis. The 2010 and 2011 criteria, in order to resolve these issues, eliminated the tender point exam as a requirement for diagnosis and included accompanying non-pain-related symptoms as an integral part of the diagnosis. However, the criteria failed to include patients with secondary FM. The revised 2016 criteria altered the definition of generalized pain to avoid inclusion of patients with regional pain syndromes, as occurred in the 2010/2011 criteria. Additionally, it allowed the diagnosis of FM irrespective of other diagnosis, similarly to the 1990 ACR criteria. Finally, the AAPT Criteria’s multidimensional approach was adopted in order to allow the identification of the syndrome in clinical practice. It focuses on widespread pain as the core criteria, and other aspects act as confirmatory factors. However, the AAPT criteria had the worst performance with a sensitivity of 73.8% compared to 79.8% and 78% for the ACR 2011 criteria and ACR 2016 criteria, respectively. Further research is required to allow a more accurate and convenient diagnosis of FM in clinical practice.