Management of dactylitis in patients with psoriatic arthritis: an updated literature review informing the 2021 GRAPPA treatment recommendations

Objective This literature review aimed to identify the most efficacious current interventions for dactylitis and provide up-to-date scientific evidence to support the 2021 Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) recommendations on the management of psoriatic arthritis.

Methods Original articles published from 2013 to 2020, registered in MEDLINE, Embase, and Cochrane Library, describing interventional trials and reporting dactylitis-related outcomes were included. The 20 members of the GRAPPA dactylitis group were divided into 9 subgroups according to treatment, and members of each group independently extracted data from articles/abstracts corresponding to their group by using a standardized data extraction form.

Results Forty-nine publications were analyzed, representing 40 randomized clinical trials (RCTs) and including 16,752 patients. Dactylitis was assessed as a secondary outcome in 97.5% of these trials and more than 40% of RCTs did not employ a specific dactylitis measure or instrument.

Conclusion The emergence of agents with novel mechanisms of action in recent years, such as interleukin 17 (IL-17), IL-12/23, IL-23, and Janus kinase inhibitors, has significantly expanded the available treatment options for dactylitis. This article points out the lack of consensus regarding dactylitis assessment and the paucity of data concerning the effect of local steroid injections, nonsteroidal antiinflammatory drugs, and conventional disease-modifying antirheumatic drugs. Clinical trials evaluating the effect of these traditional and low-cost medications used to treat dactylitis should be encouraged.