Scleroderma-overlap syndromes: capillaroscopy, laboratory, and clinical manifestations and follow-up compared to scleroderma patients

Abstract

Introduction: Overlap syndrome (OS) is a group of systemic connective tissue diseases (CTDs) that meet the criteria of two or more CTDs. In this study, we evaluated clinical, laboratory, and capillaroscopic manifestations of patients with scleroderma OS (SSc-OS) and its subgroups and follow-up progression compared to patients with limited SSc (LcSSc).

Material and methods: In a 10-year cross-sectional study, we evaluated 135 adult patients (70 with SSc-OS and 65 with LcSSc) with the same skin score for their baseline and follow-up clinical, laboratory, high-resolution chest tomography (HRCT), echocardiography, and nailfold capillaroscopy data and compared them.

Results: Of the 135 patients, 70 had SSc-OS, including 45 (64.3%) cases of SSc-SS (Sjögren's syndrome), 11 (15.7%) of SSc-RA (rheumatoid arthritis), 9 (12.9%) of SSc-myositis and 5 (1.7%) of SSc-SLE (systemic lupus erythematosus), and 65 had LcSSc. Lung and heart involvement and pulmonary arterial hypertension (PAH) did not differ between the two groups (p > 0.05). Musculoskeletal involvement and non-specific pattern of capillaroscopy were higher (p = 0.035 and p = 0.001), and digital ulcer (DU) and scleroderma patterns of capillaroscopy were lower in the SSc-OS group (p = 0.000).No significant relationship was found between capillaroscopic patterns and organ involvement in the two groups (p-value > 0.05). In the follow-up (3.71 ±2.63 years), new DU and progression of lung involvement (p = 0.002) and the progression in capillaroscopic patterns was lower in SSc-OS (p = 0.000). In the follow-up, new DU was not seen in the SSc-OS, with lower progression of lung involvement, skin score, and capillary damage.

Conclusions: In SSc-OS patients, the most common subgroup was SSc-SS. Scleroderma OS was associated with lower major organ involvement and capillaroscopy progression than LcSSc. Major organ involvement in patients with SSc-OS was significantly lower than in LcSSc patients. In the follow-up, new DU was not seen in the SSc-OS with lower progression of lung involvement, skin score, and capillary damage.

Keywords: interstitial lung disease; nailfold capillaroscopy; pulmonary arterial hypertension; scleroderma; scleroderma-overlap.