Treatment considerations in patients with concomitant viral infection and autoimmune rheumatic diseases.

Widespread use of immunosuppressive drugs, both conventional disease-modifying antirheumatic drugs (cDMARDs) and biologic disease-modifying antirheumatic drugs (bDMARDs), in autoimmune rheumatic diseases (ARDs) has been found to be associated with the reactivation of underlying latent viruses. The clinical features of virus reactivation can sometimes mimic flare of the underlying ARDs. The correct diagnosis and management of such reactivation is crucial, as increasing the dose of immunosuppressive drugs to treat a presumed flare of underlying ARDs would probably be of no benefit, and it could exert a detrimental effect on the host. This review focused on the effects of immunosuppressive drugs on underlying chronic viral infections, particularly hepatitis B virus, hepatitis C virus, human immunodeficiency virus, varicella zoster virus, Epstein-Barr virus, cytomegalovirus, John Cunningham (JC) virus, Kaposi sarcoma-associated herpesvirus, and human papillomavirus in patients with ARDs. It also covered the effect of interferon-α, which is used to treat chronic hepatitis infection, and the induction of autoimmunity.