Identification and characteristics of patients with potential difficult-to-treat Psoriatic Arthritis: exploratory analyses of the Greek PsA registry.

OBJECTIVE: To present the characteristics of patients with potential difficult-to-treat (D2T) psoriatic arthritis (PsA). METHODS: We used data from the Greek multicentre registry of PsA patients. D2T-PsA was defined as follows: patients with at least 6-months disease duration, who have failed to at least 1 csDMARD and at least 2 bDMARDs/tsDMARDs with a different mechanism of action and have either at least moderate disease activity (MODA) defined as DAPSA > 14, and/or are not at minimal disease activity (MDA). Demographic and clinical characteristics were compared between D2T and non-D2T PsA patients. In two sensitivity analyses, patients classified as D2T solely according to the MODA or MDA criterion were examined separately. RESULTS: Among 467 patients included, 77 (16.5%) were considered D2T and 390 non-D2T PsA. Compared with non-D2T, patients with D2T PsA presented more commonly with extensive psoriasis (p< 0.0001) and were more likely to have higher BMI (p= 0.023) and a history of inflammatory bowel disease (p= 0.026). In the MODA and MDA sensitivity analyses, 7.5% and 12.5% of patients were considered D2T, respectively. In both sensitivity analyses, extensive psoriasis was again identified as an independent variable for D2T PsA (p= 0.001 and p= 0.008, respectively). Moreover, female gender (p= 0.034) in the MODA analysis and axial disease (p= 0.040) in the MDA analysis were independent variables for D2T PsA. CONCLUSION: Despite the availability of therapies, D2T PsA is common in real-life cohorts of patients with PsA and extensive psoriasis. High BMI, female gender, axial-disease, and history of IBD were also associated with D2T PsA.

Anakinra for Refractory Pseudogout in Patients with End-stage Renal Disease on Haemodialysis.

Calcium pyrophosphate deposition (CPPD) arthritis is the second most common type of crystal-induced arthritis after gout. Acute flares are commonly treated with non-steroidal anti-inflammatory drugs, intra-articular or short-term systemic glucocorticoids or colchicine. However, since there is no pharmacological treatment to reduce CPPD crystal burden, relapsing or chronic CPPD arthritis may be challenging to treat, particularly in patients with end-stage renal disease who are at risk for toxicity of the above medications. Since IL-1ß appears to be driving CPPD arthritis, we treated two patients with chronic CPPD arthritis and end-stage renal disease on haemodialysis with the IL-1ß receptor antagonist anakinra. In both patients, arthritis resolved quickly, while continuation of anakinra maintained remission and allowed complete glucocorticoid withdrawal. Therefore, anakinra may be a safe and effective option both for short and long-term treatment of CPPD arthritis in patients on chronic renal replacement therapy.