JC virus reactivation in patients with autoimmune rheumatic diseases treated with rituximab

To evaluate the presence of John Cunningham virus (JCV) DNA in patients with autoimmune rheumatic diseases (ARDs) treated with rituximab (RTX).

We assessed the JCV DNA levels in peripheral blood mononuclear cell (PBMC), serum, and urine samples by quantitative real-time polymerase chain reaction (qPCR) in a cohort of 42 ARD patients (20 of whom were being treated with RTX) and 42 healthy donors. Approximately 1 year later, we collected further samples from 32 of these 42 ARD patients, all of whom were being treated with RTX. We studied the association between these viral DNA prevalences and various clinical and demographic variables.

The viral prevalence in PBMC, serum, and urine samples was 2.4% (1/42), 0%, and 50% (21/42), respectively, in the healthy donors, and 26% (8/31), 16% (5/31), and 86% (25/29), respectively, in the patients treated with RTX. The viral prevalences were not associated with any of the demographic or clinical variables included in the study.

We detected a viral reactivation in PBMCs and serum during the RTX treatment that did not seem to be influenced by either use of immunosuppressive drugs or the length of treatment with the monoclonal antibody. Although this reactivation was asymptomatic, the viral presence in blood could increase the probability of the appearance of a neurotrophic variant of JCV.