Risk factors associated with elevated blood cytomegalovirus pp65 antigen levels in patients with autoimmune diseases

Abstract

Objectives To further assess the relationship between elevated levels of cytomegalovirus (CMV) pp65 antigen in blood, as indicative of viral load, during treatment-free follow-up and CMV diseases in patients with autoimmune diseases and to identify any risk factors associated with elevated viral loads.Methods This was a retrospective review of the electronic medical charts of 148 patients with autoimmune diseases who tested positive for CMV pp65 antigen in the blood.Results A total of 106 patients were analyzed. During follow-up, elevated viral loads were detected in 35 patients who were not on antiviral therapy, of whom five developed CMV diseases. Elevated viral load was significantly associated with CMV diseases [5/35 vs. 0/71 (no elevated viral load); P = 0.001). Multivariate analysis revealed that lymphopenia [lymphocyte numbers < 700/mm3, odds ratio (OR) 34.44, 95 % confidence interval (CI), 7.82–151.66; P < 0.001], systemic lupus erythematosus (SLE) (OR 6.71, 95 % CI, 1.23–36.49; P = 0.028), and polymyositis/dermatomyositis (PM/DM) (OR 10.62, 95 % CI 1.41–79.77; P = 0.022) were significantly associated with elevated viral load.Conclusions Elevated viral load was significantly associated with CMV diseases. Patients with SLE or PM/DM and lymphopenia would therefore benefit from a detailed viral load follow-up and careful physical examination.