Introduction: Calcium pyrophosphate (CPP) deposition is a frequent joint disease with increased prevalence in older people in whom treatment of acute CPP arthritis with conventional therapies such as colchicine, corticosteroids or non-steroidal anti-inflammatory drugs (NSAIDs) could be contraindicated or not used at an optimal dose. As recommended in gout, anakinra might represent an alternative treatment for acute arthritis. In contrast, the relevance of anakinra in acute CPP arthritis has not given much attention. We further aimed to analyze the efficacy and safety of anakinra in acute CPP arthritis in a large cohort.
Patients and methods: We retrospectively included all patients receiving anakinra for acute CPP arthritis between January 2011 and 2017. Medical history data were collected including hypertension, diabetes mellitus, cardiovascular disease, history of gastroduodenal ulcer, renal impairment and concomitant treatments including anticoagulants or antiplatelet drugs. The following data were collected before and 4 days after the first anakinra injection: swollen joint count (SJC), tender joint count (TJC), pain score on a visual analog scale (VAS, 0-100 mm) and C-reactive protein (CRP) level. A good response was defined according the evaluation of the physician or documentation in the chart of the phrase “good response” after anakinra treatment.
Results: We included 33 patients (24 women; mean age 79.2 ±1 12.8 years). Mean duration of acute arthritis 13.2 ± 12.9 days. CPP arthritis was confirmed by the presence of CCP crystals in synovial fluid in 28/33 (84.8%) patients. For the remaining 5 patients, the diagnosis was confirmed by CPP deposition features seen on imaging. Corticosteroids, NSAIDs and colchicine were previous treatments, without significant improvement in 12 (36.4%), 7 (21.2%) and 18 (54.5%) patients, respectively. The mean dose of corticosteroids was 20.8 ±8.2 mg/day. Among the 33 patients, 32 had a documented visit at day 4. The number of good responders was 27 (81.8%). At day 4, patients showed decreased mean VAS pain score (from 64.8 ±26.5 to 21.2 ±19.7 mm, p <0.0001), TJC (5.8 ±5.0 to 1.0 ±1.0, p <0.0001), SJC (3.9 ±2.7 to 0.9 ±1.0, p <0.0001) and CRP level (116.1 ±71.6 to 26.0 ±23.1 mg/l, p <0.0001). Anakinra was well tolerated. Only one patient had pneumonitis that was resolved with oral antibacterial agents.
Conclusion: Our results suggest that anakinra could be a relevant alternative for managing acute CPP arthritis, leading to rapid relief of inflammatory symptoms, with a good tolerance.