Effects of mud-bath therapy in psoriatic arthritis patients treated with TNF inhibitors. Clinical evaluation and assessment of synovial inflammation by contrast-enhanced ultrasound (CEUS)

Objectives: Despite the efficacy of TNF inhibitors, most patients with psoriatic arthritis maintain a residual synovial inflammation. The main aim of the study was to evaluate the effects of mud-bath therapy on clinical picture of PsA patients treated with TNF inhibitors. The secondary outcome was to assess synovial inflammation in hand joints detected by contrast-enhanced ultrasound. Other aims were to verify the risk of arthritis flare and to evaluate the effects of spa treatment on functional ability and on quality of life. Methods: Thirty-six patients with psoriatic arthritis, treated in the last 6 months with TNF inhibitors, were enrolled. After 1:1 randomisation, 18 patients (group A) underwent mud-bath therapy (12 mudpacks and 12 thermal baths), maintaining treatment with TNF inhibitors; 18 patients (group B) continued pharmacological therapy alone. CRP, PASI, DAS28, swollen and tender joint count, VAS pain, HAQ and SF-36 were evaluated at baseline (T0) and after 45 days (T1). Synovial inflammation detected by contrast-enhanced ultrasound, analysed by a software system, was also assessed. Results: A significant improvement in PASI ( P< 0.005), DAS28 (P< 0.05), swollen joint count and tender joint count ( P< 0.001), and HAQ (P< 0.001) between T0 and T1 was observed in group A. No patient underwent a flare-up of arthritis. Ultrasound videos demonstrated a significant appearance delay ( P< 0.05) and faster washout (P< 0.02) of contrast dye in group A patients with respect to group B. Conclusions: These data suggest a decrease of residual synovial inflammation and a beneficial clinical effect of spa therapy in psoriatic arthritis patients treated with TNF inhibitors.