Objectives To determine sensitivity and specificity of ultrasound score (US-score) for the diagnosis of gout, by ultrasound (US) examination, of the first metatarsophalangeal (MTP1) joint.

Methods A groups of 60 patients (pts) with primary gout of the MTP1 joints were examined. Diagnosis was established by EULAR criteria for diagnosis of gout. In the group of gouty patients, only symptomatic MTP1 joints (n=83 joints) were examined by US. US findings of 60 pts (83 joints) were compared with US findings of 35 healthy controls (n=70 joints). Both groups were comparable according to age, sex and BMI. US examination was done by 18 MHz probe. The existence of: “double contour”, tophi, “starry sky” and/or “snowstorm” signs, hyperechoic cloudy areas (HCA), joint effusion, bone erosions, power Doppler signal and synovial hypertrophy were assessed. After determining the sensitivity and specificity of all these US signs individually, they were qualitative scored as 0 (absent) or 1 (present) and scored as follows: US8-US0-score “0–8”, whereby “0” means that none of the characteristics are present, and “8” means that all listed US findigns are present.

Results The area under the ROC curve for total US8-score was 0.901 ± 0.025. The diagnostic sensitivity and specificity of US8-score in the MTP1 joint was 79,5% and 85,7% respectively, if value 1,50 was determined as cut-off (table 1). The synovial hypertrophy was excluded from the equation and US7- score was calculated. According to our findings US7-score in the MTP1 joint had the best sensitivity and high specificity for diagnosis gout, because the area under the ROC curve was 0.924 ± 0.021. The sensitivity of the US7-score was 82.9% and specificity 91.7%, if value 1.50 was determined as cut-off (table 1).

Conclusions US7 score (“double contour”, tophi, “starry sky” and/or “snowstorm” signs, HCA, joint effusion, bone erosions and power Doppler signal) had highest area under the ROC curve (0,924), and highest sensitivity (82,9%) and specificity (91,7%) for the diagnosis of gout.

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Disclosure of Interest None declared