New DACTOS Score May Help Diagnose Dactylitis in PsA

The DACTylitis glObal Sonographic (DACTOS) score provides a reliable method of interpreting several sonographic features of the hand that are characteristic of dactylitis, according to researchers who developed the new scoring system.  

Dactylitis is a common feature of psoriatic arthritis (PsA). Musculoskeletal ultrasonography can readily identify inflammation typical of dactylitis in the anatomical structures of the fingers and also is useful for monitoring the effects of therapy.

In their study, the researchers sought to identify lesions characteristic of dactylitis in the hands of patients with PsA, determine the reliability of musculoskeletal ultrasonography in scoring those lesions, and develop a new scoring system to provide a global score of dactylitis lesions.

The project involved a systematic review of literature on the use of musculoskeletal ultrasonography in dactylitis associated with PsA. Then a group of 12 rheumatologists participated in a 3-round Delphi procedure to arrive at consensus on the sonographic lesions characteristic of PsA-associated dactylitis, which were subcutaneous soft tissue edema, flexor tenosynovitis, peritendon extensor inflammation, and synovitis.

The final DACTOS score was configured by adding the scores of each lesion and ranged from 0 to 25. Web- and patient-based reliability exercises performed to assess those lesions included in the score showed moderate to excellent agreement with the DACTOS score.

“The DACTOS score provides a useful global analysis of dactylitis of the hand and can represent a support to clinical diagnosis as well as a useful tool for the management and research in patients with PsA with dactylitis,” the researchers concluded.

—Rebecca Mashaw

Reference:

Zabotti A, Sakellariou G, Tinazzi I, et al. Novel and reliable DACTylitis glObal Sonographic (DACTOS) score in psoriatic arthritis. Ann Rheum Dis. 2020;79(8):1037-1043. http://dx.doi.org/10.1136/annrheumdis-2020-217191