Correlation of enthesial and synovial inflammation in patients with psoriatic arthritis: Data of clinical and ultrasonographic study

Abstract

Objective. Assessment of clinical manifestations and ultrasonographic signs of enthesitis (En) in patients with psoriasis (PsO) and psoriatic arthritis (PsA).Subjects and methods. The study is based on the analysis of survey data from 106 patients with PsO for the period 2018–2021, which were firstly sent by dermatologists for a consultation with a rheumatologist due to musculoskeletal pain. The duration of the period of musculoskeletal pain in the observed patients did not exceed 12 months. In addition to general clinical and laboratory examination, all patients underwent ultrasonography of painful and/or swollen joints, tendons and ligaments using a linear sensor (frequency – 12–18 MHz) of MyLab 50 (Esaote, Italy) apparatus and supplemented by Doppler energy study with a pulse frequency of 6.6 MHz. The OMERACT definitions were used to identify En, synovitis and tenosynovitis.Results and discussion. The diagnosis of PsA was established in 73.6%, osteoarthritis – in 13.2%, gout – in 8.4%, fibromyalgia – in 17.9%. Ultrasonographic signs of En were found in 67.9% of patients: signs of an active inflammatory process in enthesises (decreased echogenicity, thickening and appearance of Doppler signals) were observed in 48.7%, signs of structural damage to enthesial zones (calcifications, enthesophytes and bone erosions) in 25,6% of patients. Isolated En was found in 24.4% of patients, a combination of En and synovitis – in 32.1% of patients, a combination of En and tenosynovitis – in 20.5% of patients. The correlation between the inflammatory domain values of the ultrasoundographic enthesial index MASEI (Madrid Sonographic Enthesitis Index) and the clinical enthesial index LEI (Leeds Enthesitis Index) was 0.71 [0.58; 0.77]. There were less pronounced clinical indicators of enthesial inflammation (lower LEI index values), functional disorders of the joints (lower values of the HAQ-DI index) and laboratory signs of systemic inflammation (lower CRP values) in patients with isolated En in comparison with combination of En and synovitis. Ultrasonographic signs of structural damage of enthesises were observed in 15.4% of patients without clinical and ultrasonographic signs of active En, which may indicate the possibility of a subclinical course of enthesial inflammation in patients with PsO.Conclusion. It was demonstrated that ultrasonography has diagnostic capabilities to identify the site of the inflammatory process in patients with PsA and differentiate patients with isolated En and a combination of En and synovitis in order to select a method of differentiated anti-inflammatory therapy.