Reliability of OMERACT ultrasound elementary lesions in gout: results from a multicenter exercise.

The aim of this study was to evaluate the reliability of the outcome measures in rheumatology (OMERACT) definitions for ultrasound (US) elementary lesions in gout through an image reading exercise. Images from patients with gout (static images and videos) were collected. As an initial step, we carried out a image reading exercise within the experts of the Pan-American League of Associations for Rheumatology (PANLAR) US Study Group (n = 16). The following step consisted in a web-based exercise with the participation of larger number of sonographers (n = 63) from different centers. Images were rated evaluating the presence/absence of any US elementary lesion. Inter- and intra-reader reliabilities were analyzed using kappa coefficients. Participants were stratified according to their level of experience. In the first exercise, inter-reader kappa values were 0.45 for aggregates, 0.57 for tophus, 0.69 for erosions, and 0.90 for double contour (DC). Intra-reader kappa values were 0.86, 0.76, 0.80, and 0.90, respectively. The web-based exercise showed inter-reader kappa values for aggregates, tophus, erosions, and DC of 0.42, 0.49, 0.69, and 0.79, respectively. The intra-reader kappa values were 0.62, 0.69, 0.77, and 0.85, respectively. Reliability was not influenced by the sonographer's level of experience. The reliability of the new OMERACT US definitions for elementary lesions in gout ranged from moderate to excellent, depending on the type of lesion.

Ultrasound nail imaging on patients with psoriasis and psoriatic arthritis compared with rheumatoid arthritis and control subjects.

OBJECTIVE: The objective of this study was too show findings at finger nails level revealed by high-frequency gray-scale ultrasound (US) and power Doppler in patients with psoriatic arthritis (PsA),and cutaneous psoriasis compared with rheumatoid arthritis and control subjects. METHODS: We studied 35 patients with PsA, 20 with cutaneous psoriasis, and control groups (28 control subjects and 27 patients with rheumatoid arthritis). All nails of both hands were observed (1097 nails, 3 excluded because of trauma). In every patient, we classified the morphologic abnormalities disclosed in ventral and dorsal nail plates. We also measured the distance between ventral plate and the bone margin of the distal phalanx at the right index finger. RESULTS: All patients and control subjects presented abnormalities in the US imaging. Those with psoriatic arthritis and cutaneous psoriasis showed a higher number of compromised nails. When classifying those abnormalities using the typology of Wortsman et al, patients with psoriatic arthritis showed loosening of the borders of the ventral plate (type II), whereas patients with cutaneous psoriasis showed focal hyperechoic involvement of the ventral plate without involvement of the dorsal plate (type I). Patients of the control group could not be classified, although 31 of 55 showed thinning of the ventral plate without hyperechoic deposits. Nineteen of 35 patients with psoriatic arthritis, and 10 of 20 patients with cutaneous psoriasis did not show any nail clinical alterations. Nevertheless, the US detected type II alterations in the first group and type I in the second group. Patients with psoriatic arthropathy had power Doppler increases in distal interphalangeal joints and nail beds in a statistically significant form (P = 0.0001).When measuring the distance between the ventral plate and the bone margin of the distal phalanx, there was homogeneity among samples in patients and control subjects. A receiver operating characteristic curve analysis determined that a cut point of 2 mm clearly defined these 2 groups. There was a significant difference (P < 0.0001) between the mean distance ventral plate-osseous margin of the distal phalanx in psoriatic arthritis patients (P = 0.001) and patients with cutaneous psoriasis (P = 0.005) versus rheumatoid arthritis patients (P = 0.548). CONCLUSIONS: As a predominant finding in our study, we observed abnormalities of the ventral plate in patients with PsA (type II) and abnormalities (type I) in patients with cutaneous psoriasis. We found a significant difference between the mean distance ventral plate-osseous margin of the distal phalanx in patients with PsA and patients with cutaneous psoriasis versus control subjects. Ultrasound imaging could be a feasible and sensitive tool to describe, measure, and follow morphologic characteristics and changes of the nail in psoriatic and/ or psoriatic arthritis patients with or without clinical nail lesions.

Pachydermodactyly: four additional cases.

Pachydermodactyly (PDD) is a rare, benign form of digital fibromatosis characterized by an asymptomatic soft tissue swelling affecting the skin of the lateral aspects of the proximal interphalangeal joints of the fingers, and it sometimes can be misdiagnosed with some rheumatic condition. Recognition on these features should lead to its more frequent diagnosis. The purpose of our study is to report four additional cases of PDD and discuss the differential diagnosis.