Cytomegalovirus in Indian systemic lupus erythematosus patients: troublemaker or onlooker?

INTRODUCTION: cytomegalovirus (CMV) infection has been reported to be associated with onset/exacerbation of systemic lupus erythematosus (SLE). In an attempt to verify this, we studied CMV infection in SLE patients. METHODS: forty-two SLE patients were studied at 3-time points; disease onset/flare, at peak of immunosuppression (at 6 weeks) and at low doses of immunosuppression (at 6 months). We studied healthy blood donors as controls, only once. Clinical assessment and SLE Disease Activity Index scoring were done at each visit. RT-PCR and ELISA were performed to detect CMV viral-load and anti-CMV antibodies (Ab) respectively. RESULTS: nine of 106 patients had detectable viral-load (145-50,000 copies/ml). Of these nine, three patients had significant viral-load, 6 patients had low viral-loads of doubtful clinical significance. None of the patients developed CMV disease. Six of 42 cases were positive for IgM Abs. All controls were negative for CMV DNA as well as CMV IgM Abs. All samples from patients and controls were positive for CMV IgG Ab indicating widespread prevalence. CONCLUSION: significantly, a higher seroprevalence of CMV IgM Abs against CMV observed in SLE patients when compared to controls, indicating possible reactivation due to immune modulation.