Steroid injection effective in psoriatic hand dactylitis confirms sonographic evaluation

Italy: Psoriatic arthritis (PsA) is the most common disease that causes dactylitis due to joint, tendon, and soft tissue inflammation. Studies show ultrasound as a tool for assessment of treatment of psoriatic dactylitis has been effective with limited studies.

An observational study by Nicolo Girolimetto and team revealed that a single steroid injection into or in close proximity to the digital flexor tendon sheath was sufficient to determine an important ultrasonographic and clinical response, maintained at 3 months.

Ultrasound confirmed the effectiveness of steroid injection on dactylitis by demonstrating that it involves the resolution of extra-articular inflammation, in particular, flexor tenosynovitis and soft tissue edema. The findings of this study are published in the journal Rheumatology and Therapy.

The study aimed to assess ultrasound effectiveness of steroid injection into the digital flexor tendon sheath for the treatment of psoriatic dactylitis compared to systemic treatment alone. 

The study was observational, multicentre, prospective study, hand dactylitis were evaluated clinically and sonographically by high-frequency ultrasound (US) probe in both GreyScale (GS) and power Doppler (PD). The presence of Flexor Tenosynovitis (FT), Soft Tissue Oedema (STO), Peritendon extensor inflammation, and synovitis was assessed before treatment, at 1-month (T1) and 3-months (T3) follow-up. LT was proposed to all patients. Patients refusing LT were treated with oral NSAIDs. US response was defined for DACTOS score < 3 and US remission for DACTOS score = 0.

A total of 88 patients with symptomatic hand was included in the study. At T3 evaluation the ST group showed a significantly higher persistence (grade > 1) of FT and STO and MCP synovitis.

The results of the study were

• US remission was seen only in the LT group (at T3 31% vs. 0).

• The percentage of patients with DACTOS < 3 were found to be significantly greater in the LT group compared with ST group, at both T1 (49% vs. 5%) and T3 evaluation (76% vs. 7%).

• In multiple conditional logistic regression analysis, the only factor associated with US remission was LT (T3 odds ratio = 41.21, p < 0.001).

The researchers concluded that "Ultrasound confirmed the effectiveness of steroid injection for dactylitis by demonstrating that it involves the resolution of extra-articular inflammation, in particular FT and STO."

Reference:

GirolimettoGirolimetto, N., Macchioni, P., Tinazzi, I. et al. Ultrasound Effectiveness of Steroid Injection for hand Psoriatic Dactylitis: Results from a Longitudinal Observational Study. Rheumatol Ther (2021).

https://doi.org/10.1007/s40744-021-00383-z