Two cases of human parvovirus B19 infection-associated anemia after pediatric liver transplantation

Objective To explore the diagnosis and treatment of parvovirus B19 infection-associated anemia after pediatric liver transplantation (LT). Methods The clinical data were retrospectively reviewed for 2 children with severe anemia caused by parvovirus B19 infection after LT. Case 1 was a 2-year-old girl with a weight of 10.7 kg. Classical orthotopic LT was performed due to ornithine carbamoyltransferase deficiency. Hemoglobin level began to progressively decline since Day 2 post-transplantation. And case 2 was a 5-month-old girl with an age of 5 months and a weight of 7.2 kg. She underwent classic orthotopic LT for biliary atresia and decompensated liver cirrhosis. Hemoglobin level progressively declined at nearly 2 months post-transplantation. Results In case 1, bone marrow aspiration was performed at Day 54 post-transplantation. There was pure red cell aplasia and the detection of microvirus B19 nucleic acid was positive. Intravenous immunoglobulin was prescribed at a dose of 2.5 g/day for 10 days, tacrolimus was switched to cyclosporine and hemoglobin level spiked from 62 to 105 g/L after one-month treatment. In case 2, hemoglobin decreased to 44 g/L at 2.5 months post-transplantation and the result of polymerase chain reaction of parvovirus B19 was 9.7×107copies/ml. Then intravenous immunoglobulin was dosed at 2.5 g/day for 10 days and hemoglobin level rose to 122 g/L at 25 days after treatment. Hemoglobin level decreased to 63 g/L again at 4.5 months post-transplantation. Anemia was corrected by intravenous immunoglobulin injection plus a temporary discontinuation of tacrolimus and a reduced dose of tacrolimus. Conclusions Infection of parvovirus B19 can cause pure red cell aplasia after LT in children. Early diagnosis with intravenous immunoglobulin and modification of immunosuppressive regimen can obtain excellent therapeutic efficacies. Key words: liver transplantation; children; parvovirus B19; pure red cell aplasia