Parvovirus B19 viremia in children with systemic lupus erythematosus

Background: Parvovirus B19 infection may present with fever, rash, non-erosive arthritis, hepatitis, anemia, thrombocytopenia, leucopenia and positive ANA, B19 infection may be misdiagnosed as new onset systemic lupus erythematosus. At the same time, B19 infection and systemic lupus erythematosus may occur simultaneously in some patients. A casual relationship between B19 infection and classic idiopathic systemic lupus erythematosus has not been demonstrated yet. Objectives: This study was undertaken to investigate the seroprevalence of parvovirus B19 in SLE patients and to search for the different correlates of this viremia with positive results. Methods: This case-control study was conducted on 30 patients with SLE and 30 normal controls. All the children were subjected to detailed medical history, Clinical examination, laboratory estimation as sera from them were examined for parvovirus B19 infection by serological assays using nested polymerase chain reaction and IgG and IgM antiB19 antibodies by ELISA. Results: Parvovirus B19 DNA was detected in 11 of the 30 patients with SLE (33.3 percent) while it was not detected in any of our normal controls. Of the 11 patients with B19 DNA, only two had IgG anti-B19 antibody and one had IgM anti-B19 antibodies, whereas IgG and IgM anti-B19 antibodies were detected in 11(57.8%) and 9 (47.3%) of 19 SLE patients without B19 DNA respectively. B19 DNA was found more commonly in sera from SLE patients without anti-B19 antibodies than in those with anti-B19 antibodies (P < 0.05). Conclusions: parvovirus B19 might induce either idiopathic SLE in a person who is genetically susceptible or it might induce a SLE-like picture. Parvovirus B19 infection in patients with SLE may be due to lack of anti-B19 antibodies because of either the immunocompromised nature of the host or the use of immunosuppressive drugs. There was a higher prevalence of hypocomplementemia in patients with parvovirus B19 viremia than in those without parvovirus.