Analysis of immune cells in a patient with post-transfusion hepatitis caused by human cytomegalovirus

Cellular immune responses are associated with the pathogenesis of human cytomegalovirus (HCMV) hepatitis. We investigated a patient with post-transfusion HCMV hepatitis. A 9 year-old girl was involved in a traffic accident and suffered from traumatic damage to the left kidney and diaphragm and received a pelvic bone fracture. At emergency surgery she was transfused with 1200 ml of fresh whole donor blood. Abnormal liver function was observed in the 10 days after surgery. Titers of serum anti-HCMV IgG and IgM antibodies were elevated at 11, 17 and 25 weeks after operation. We analyzed the surface markers of peripheral blood mononuclear cells obtained 21 weeks after surgery. The CD4/CD8 ratio and the number of CD16 + CD56 decreased. We detected HCMV immediate early (IE) DNA in the fractionated peripheral blood cells (polymorphonuclear leukocytes, CD2+, CD4+ and CD8+ T lymphocytes) by polymerase chain reaction. The histology of liver biopsy at 23 weeks after operation showed the findings of acute hepatitis and the absence of HCMV IE antigen. It was considered that the immunosuppressive condition associated with the trauma, operation or transfusion itself induced the reactivation of HCMV or that transfused blood cells infected with HCMV caused reinfection. It was also speculated that HCMV hepatitis was not only due to the direct damage of hepatic cells by HCMV, but also due to the cellular immune responses associated with HCMV infection.