Rituximab therapy in primary Sjögren's syndrome with interstitial lung disease: a retrospective cohort study

Interstitial lung disease (ILD) is one of the major systemic manifestations of primary Sjögren's syndrome (pSS). The aim of this study was to evaluate the therapeutic effect of rituximab on pSS patients with ILD.

Pulmonary function test results, including diffusing capacity for carbon monoxide (DLCO) and DLCO/alveolar volume (Va) ratio, and high-resolution computed tomography (HRCT) findings/scores in ten pSS patients with ILD treated with rituximab were retrospectively investigated. Global disease, fatigue, dryness of eyes and mouth, shortness of breath, and cough were assessed by visual analogue scales (VAS, 0-100 mm).

At 6 months after rituximab treatment, improvement in pulmonary function was observed (from 49.3±12.6 to 56.9±11.4% for DLCO, p=0.011; from 74.4±15.8 to 85.6±10.3% for DLCO/Va, p=0.021). Similarly, significant improvement of subjective symptoms were also noted after treatment (VAS global disease, from 62.0±11.4 to 26.0±10.8 mm, p<0.001; VAS fatigue, from 38.0±23.0 to 18.0±7.9 mm, p=0.006; VAS dryness of eyes, from 53.0±24.4 to 29.0±13.7 mm, p=0.004; VAS dryness of mouth, from 45.0±14.3 to 28.0±9.2 mm, p=0.001; VAS shortness of breath, from 64.0±16.5 to 31.0±16.0 mm, p<0.001; VAS cough, from 42.0±23.5 to 18.0±10.3 mm, p=0.011). The mean HRCT score decreased after rituximab therapy although to a lesser extent (from 8.7±4.1 to 7.6±4.6, p=0.419). An adverse event was observed in only one patient who had non-fatal pneumonia 4 months after rituximab infusion.

Rituximab was effective in improving clinical symptoms and gas exchange, and in stabilising HRCT score in pSS patients with ILD.