Background Enthesitis are characteristic for psoriatic arthritis (PsA) and can be manifestations of the early stage of this disease.
Objectives To investigate the presence of lower limbs entheseal abnormalities and to determine clinical significant of enthesitis in early PsA.
Methods 51 patients (28 women, 23 men) with early PsA (mean age 43±13.8 yrs; disease duration 11.5±6.9 months; psoriasis duration was 11 yrs) were enrolled. All patients were tested to determined of dactylitis and psoriatic onychodystrophy, clinical assessment of swollen and tender Achilles tendon and planter aponeurosis, disease activity index (DAS28), C-reactive protein by highly sensitive method (hsCRP). Radiographs of the hands and feet were observed using the Sharp’s method modified by van der Heijde including distal interphalangeal joints. All patients were underwent ultrasonography (US) by the apparatus Voluson-I (GE) using a 4-13 MHz linear-array transducer. The reduced index GUESS was applied for score of enthesitis: Achilles tendon thickness >5.29 mm, retrocalcaneal bursitis, posterior pole of calcaneus erosion, posterior pole of calcaneus enthesophyte, plantar aponeurosis thickness >4.4 mm, inferior pole of calcaneus erosion, inferior pole of calcaneus enthesophyte. Total possible score on belateral lower limb is 14.
Results On clinical examination 16 (31.4%) entheseal sites were abnormal and on US examination 35 (68.6%) sites were abnormal, (p=0.0002). Achilles tendon thickness was found in 15 (29.4%) patients with early PsA, retrocalcaneal bursitis – in 4 (7.8%), plantar aponeurosis thickness – in 27 (53%), calcaneus erosion – in 3 (6%), calcaneus enthesophyte – in 20 (39.2%). The dactylitis were detected in 25 (49%) patients and psoriatic onychodystrophy – in 27 (53%). Median DAS28 index was 4.8 [3.3; 5.6], median hsCRP - 9.3 [2.1; 28], mean Sharp’s index - 32±5.0. Index GUESS of patients was from 1 to 6 point (mean 2.4±0.2). There was significant correlation between the index GUESS and high degree of the disease activity - DAS28 (r=0.49, p=0.0001), hsCRP (r=0.43, p=0.001), dactylitis (r=0.32, p=0.02), index Sharp (r=0.30, p=0.03) and onychodystrophy (r=0.34, p=0.01).
Conclusions The enthesitis as characteristic symptom of PsA were found the early stage of the disease in high percentage. They associated with higher degree of inflammatory activity of the disease, dactylitis, psoriatic onychodystrophy and with higher incidence of erosive disease. This study has shown the US may be useful in the detection of entheseal abnormality in early PsA patients than clinical examination.
Disclosure of Interest None Declared