Rituximab in Connective Tissue Disease–associated Interstitial Lung Disease: A Community-based Experience and Review of Literature

Interstitial lung disease (ILD) is an important manifestation of the connective tissue disorders (CTD), which can lead to significant morbidity and mortality. Conventional therapy involves immunosuppression. Rituximab (RTX), a chimeric monoclonal antibody leading to B-cell depletion, appears to have some benefit in different forms of CTD-ILD. Our community-based, university-affiliated ILD clinic receives referrals from various medical practitioners in the community, including non-university based rheumatologists. The approach to the assessment and management of these patients is multidisciplinary and involves discussions with our center’s radiologists, pathologists (as applicable) and the referring rheumatologists (either university-affiliated or community-based). Therapy is initiated or changed in collaboration with the involved rheumatologists. Patients are followed clinically, functionally (using pulmonary function tests and 6-minute-walk testing), and radiologically using high-resolution chest computed tomography scans (HRCT). Among the patients referred to our clinic with CTD-ILD, six of them received RTX primarily for progressive pulmonary disease. The mean age was 51 years. All the patients were women. One patient had mixed connective tissue disease (MCTD), one patient had Sjögren’s syndrome, one patient had polymyositis, one patient had rheumatoid arthritis and two patients had antisynthetase syndrome. Among the six patients, community-based rheumatologists in private practice were managing four. Two patients received RTX prior to referral to our clinic. Four of the six patients demonstrated clinical improvement and stability in their lung function while on RTX. Three of the six patients demonstrated definite radiologic improvements. One patient developed anaphylactic symptoms and one patient developed a life-threatening infection. There is a growing body of medical literature describing the use of RTX in CTD-ILD most of which are from case series and non-controlled studies. In our university-affiliated, community-based ILD clinic, patients with CTD-ILD are co-managed with the collaborating rheumatologists. Rituximab appears to have a beneficial effect in patients with progressive ILDs in various forms of CTDs. However, serious complications can occur and careful consideration should be given to patient selection and close follow up.