Objective: Calcium pyrophosphate deposition (CPPD) disease is prevalent and has diverse presentations, but there are no validated classification criteria for this symptomatic arthritis. The American College of Rheumatology (ACR) and EULAR have developed the first‐ever validated classification criteria for symptomatic CPPD disease.Methods: Supported by the ACR and EULAR, a multinational group of investigators followed established methodology to develop these disease classification criteria. The group generated lists of candidate items and refined their definitions, collected de‐identified patient profiles, evaluated strengths of associations between candidate items and CPPD disease, developed a classification criteria framework, and used multi‐criterion decision analysis to define criteria weights and a classification threshold score. The criteria were validated in an independent cohort.Results: Among patients with joint pain, swelling, or tenderness (entry criterion) whose symptoms are not fully explained by an alternative disease (exclusion criterion), the presence of crowned dens syndrome or calcium pyrophosphate crystals in synovial fluid are sufficient to classify a patient as having CPPD disease. In the absence of these findings, a score >56 points using weighted criteria, comprising clinical features, associated metabolic disorders, and results of laboratory and imaging investigations, can be used to classify as CPPD disease. These criteria had a sensitivity of 92.2% and specificity of 87.9% in the derivation cohort (190 CPPD cases, 148 mimickers), whereas sensitivity was 99.2% and specificity was 92.5% in the validation cohort (251 CPPD cases, 162 mimickers).Conclusion: The 2023 ACR/EULAR CPPD disease classification criteria have excellent performance characteristics and will facilitate research in this field.

Objective Calcium pyrophosphate deposition (CPPD) disease is prevalent and has diverse presentations, but there are no validated classification criteria for this symptomatic arthritis. The American College of Rheumatology (ACR) and EULAR have developed the first-ever validated classification criteria for symptomatic CPPD disease. Methods Supported by the ACR and EULAR, a multinational group of investigators followed established methodology to develop these disease classification criteria. The group generated lists of candidate items and refined their definitions, collected de-identified patient profiles, evaluated strengths of associations between candidate items and CPPD disease, developed a classification criteria framework, and used multi-criterion decision analysis to define criteria weights and a classification threshold score. The criteria were validated in an independent cohort. Results Among patients with joint pain, swelling, or tenderness (entry criterion) whose symptoms are not fully explained by an alternative disease (exclusion criterion), the presence of crowned dens syndrome or calcium pyrophosphate crystals in synovial fluid are sufficient to classify a patient as having CPPD disease. In the absence of these findings, a score>56 points using weighted criteria, comprising clinical features, associated metabolic disorders, and results of laboratory and imaging investigations, can be used to classify as CPPD disease. These criteria had a sensitivity of 92.2% and specificity of 87.9% in the derivation cohort (190 CPPD cases, 148 mimickers), whereas sensitivity was 99.2% and specificity was 92.5% in the validation cohort (251 CPPD cases, 162 mimickers). Conclusion The 2023 ACR/EULAR CPPD disease classification criteria have excellent performance characteristics and will facilitate research in this field.

Objective: To assess the reliability and diagnostic accuracy of new radiographic imaging definitions developed by an international multidisciplinary working group for identification of calcium pyrophosphate deposition (CPPD).Methods: Patients with knee osteoarthritis scheduled for knee replacement were enrolled. Two radiologists and 2 rheumatologists twice assessed radiographic images for presence or absence of CPPD in menisci, hyaline cartilage, tendons, joint capsule, or synovial membrane, using the new definitions. In case of disagreement, a consensus decision was made and considered for the assessment of diagnostic performance. Histologic examination of postsurgical specimens under compensated polarized light microscopy was the reference standard. Prevalence‐adjusted bias‐adjusted kappa values were used to assess reliability, and diagnostic performance statistics were calculated.Results: Sixty‐seven patients were enrolled for the reliability study. The interobserver reliability was substantial in most of the assessed structures when considering all 4 readers (κ range 0.59–0.90), substantial to almost perfect among radiologists (κ range 0.70–0.91), and moderate to almost perfect among rheumatologists (κ range 0.46–0.88). The intraobserver reliability was substantial to almost perfect for all the observers (κ range 0.70–1). Fifty‐one patients were included in the accuracy study. Radiography demonstrated an overall specificity of 92% for CPPD, but sensitivity remained low for all sites and for the overall diagnosis (54%).Conclusion: The new radiographic definitions of CPPD are highly specific against the gold standard of histologic diagnosis. When the described radiographic findings are present, these definitions allow for a definitive diagnosis of CPPD, rather than other calcium‐containing crystal depositions; however, a negative radiographic finding does not exclude the diagnosis.

Purpose of Review: Fibromyalgia Syndrome (FMS) is a complex chronic pain condition characterized by widespread musculoskeletal pain and numerous other debilitating symptoms. The purpose of this review is to provide a comprehensive overview, based on everyday clinical practice, of the drugs presently employed in the treatment of FMS. Recent Findings: The treatment of FMS is based on a multimodal approach, with pharmacologic treatment being an essential pillar. The drugs used include tricyclic antidepressants, serotonin and noradrenaline reuptake inhibitors, other antidepressants, anticonvulsants, myorelaxants, and analgesics. The effectiveness of these medications varies, and the choice of drug often depends on the specific symptoms presented by the patient. Many drugs tend to either address only some domains of the complex FMS symptomatology or have a limited effect on pain. Summary: Each treatment option comes with potential side effects and risks that necessitate careful consideration. It may be beneficial to divide patients into clinical subpopulations, such as FMS with comorbid depression, for more effective treatment. Despite the complexities and challenges, the pharmacological treatment remains a crucial part for the management of FMS. This review aims to guide clinicians in prescribing pharmacological treatment to individuals with FMS.

Very little is known on the efficacy and safety of drugs for the management of chronic calcium pyrophosphate (CPP) crystal inflammatory arthritis. To describe the drugs used in the management of chronic CPP crystal inflammatory arthritis in expert European centres, and to examine treatment retention. This was a retrospective cohort study. Charts from patients with a diagnosis of persistent inflammatory and/or recurrent acute CPP crystal arthritis were reviewed in 7 European centres. Baseline characteristics were collected, and visits at months 3, 6, 12 and 24 included an assessment of treatment response and safety. 194 treatments were initiated in 129 patients. Colchicine (was used first-line in n = 73/86), methotrexate (used first-line in n = 14/36), anakinra (n = 27) and tocilizumab (n = 25) were the most prescribed treatments, while long-term corticosteroids, hydroxychloroquine, canakinumab and sarilumab were used occasionally. The 24-months on-drug retention was higher for tocilizumab (40%) than anakinra (18.5%)(p< 0.05), while the difference between colchicine (29.1%) and methotrexate (44.4%) was not statistically significant (p= 0.10). Adverse events lead to 14.1% of colchicine discontinuations (100% of diarrhoea), 4.3% for methotrexate, 31.8% for anakinra and 20% for tocilizumab, all other discontinuations were related to insufficient response or losses to follow-up. Efficacy outcomes did not differ significantly between treatments throughout follow-up. Daily colchicine is the first-line therapy used in chronic CPP crystal inflammatory arthritis, which is considered efficient in a third to half of cases. Second-line treatments include methotrexate and tocilizumab, which have higher retention than anakinra.