The 2023 ACR/EULAR classification criteria of CPPD [14]
| Criteria | |
|---|---|
| Entry criterion | |
| - Ever had at least one episode of joint pain, swelling, or tenderness (in a peripheral joint or axial joint such as C1/C2 in the case of crowned dens syndrome). | |
| Absolute exclusion criteria | |
| - All symptoms more likely explained by an alternate condition (e.g., rheumatoid arthritis, gout, psoriatic arthritis, OA, etc.). | |
| Sufficient criteria | |
| - Crowned dens syndrome (as characterized by both clinical and imaging features).- Synovial fluid analysis demonstrating CPP crystals in a joint with swelling, tenderness or pain. | |
| Additional classifications | |
| - An individual is classified as CPPD if the entry criterion is met, exclusion criteria are not met, and at least one sufficient criterion is fulfilled.- If none of the sufficient criteria are present, an individual is classified as CPPD disease if the sum of the criteria below is > 56 points. | |
| Scoring guidelines | |
| - Items can be scored if they were ever present during a patient’s lifetime.- If a patient fulfills > 1 item in a given domain, only the highest weighted item will be scored.- Imaging of at least one symptomatic joint by CR, US, CT, or DECT is required. | |
| Domains and levels | Points |
| A. Age at onset of joint symptoms | |
| ≤ 60 years | 0 |
| > 60 years | 4 |
| B. Time-course and symptoms of inflammatory arthritis | |
| No persistent or typical inflammatory arthritis | 0 |
| Persistent inflammatory arthritis (ongoing joint swelling with pain and/or warmth in one or more joints) | 9 |
| 1 typical acute arthritis episode (episode with acute onset or acute worsening of joint pain with swelling and/or warmth that resolves regardless of treatment) | 12 |
| More than 1 typical acute arthritis episode | 16 |
| C. Sites of typical episode(s) of inflammatory arthritis in peripheral joints | |
| 1st MTPJ | -6 |
| No typical episode(s) | 0 |
| Joint(s) other than wrist, knee, or 1st MTPJ | 5 |
| Wrist | 8 |
| Knee | 9 |
| D. Related metabolic diseases (hereditary hemochromatosis, primary hyperparathyroidism, hypomagnesemia, Gitelman syndrome, hypophosphatasia, or a familial history of CPPD disease) | |
| None | 0 |
| Present | 6 |
| E. Synovial fluid crystal analysis from a symptomatic joint | |
| CPP crystals absent on ≥ 2 occasions | –7 |
| CPP crystals absent on 1 occasion | –1 |
| Not performed | 0 |
| F. OA of hand/wrist on imaging | |
| None of the following findings or no wrist/hand imaging performed | 0 |
| Bilateral radio-carpal joints | 2 |
| ≥ 2 of the following: STTJ OA without 1st CMCJ OA; 2nd MCPJ OA; 3rd MCPJ OA | 7 |
| G. Imaging evidence of CPPD in symptomatic peripheral joint(s) | |
| None on US, CT, or DECT (and absent on CR or CR not performed) | –4 |
| None on CR (and US, CT, DECT not performed) | 0 |
| Present on either CR, US, CT, or DECT | 16 |
| H. Number of peripheral joints with evidence of CPPD on any imaging modality | |
| None | 0 |
| 1 | 16 |
| 2–3 | 23 |
| ≥ 4 | 25 |
ACR: American College of Rheumatology; EULAR: European League Against Rheumatism; CPPD: calcium pyrophosphate deposition disease; CPP: calcium pyrophosphate; CR: conventional X-ray radiography; US: ultrasound; CT: computed tomography; DECT: dual-energy computed tomography; MTPJ: metatarsophalangeal joint; OA: osteoarthritis; STTJ: scaphotrapeziotrapezoid joint; CMCJ: carpometacarpal joint; MCPJ: metacarpophalangeal joint
Note. Adapted with permission from “The 2023 ACR/EULAR classification criteria for calcium pyrophosphate deposition disease” by Abhishek A, Tedeschi SK, Pascart T, Latourte A, Dalbeth N, Neogi T, et al. Ann Rheum Dis. 2023;82:1248–57 (https://ard.bmj.com/content/82/10/1248). © Author(s) (or their employer(s)) 2023.
