Long-term parvovirus B19 infections with genetic drift after cord blood transplantation complicated by persistent CD4+ lymphocytopenia.
A 5-month-old girl was diagnosed with Langerhans cell histiocytosis and received unrelated umbilical cord blood transplantation at the age of 14 months. After cord blood transplantation, CD4(+) lymphocytopenia from unknown causes was observed, and persistent infections with human parvovirus B19 (B19) occurred. We performed repeated longitudinal genetic analysis for B19, which revealed 6 nucleotide mutations in B19 nonstructural protein regions in the patient. The resulting changes of the nonstructural 1 structure may have altered antigenicity of the virus and could play a role in the pathogenesis of persistent infection under immunocompromised conditions.
*Department of Pediatrics, Nagoya University Graduate School of Medicine, Nagoya †Gunma Prefectural Institute of Public Health and Environmental Sciences, Gunma ‡Infectious Disease Surveillance Center, National Institute of Infectious Diseases, Tokyo, Japan.
Michio
M
Suzuki
Yoshinori
Y
Ito
Akira
A
Shimada
Mika
M
Saito
Hideki
H
Muramatsu
Asahito
A
Hama
Yoshiyuki
Y
Takahashi
Hirokazu
H
Kimura
Seiji
S
Kojima
D015496:CD4-Positive T-Lymphocytes / Q000166:cytology; D002675:Child, Preschool; D036101:Cord Blood Stem Cell Transplantation / Q000009:adverse effects*; D005260:Female; D040961:Genetic Drift; D006801:Humans; D008231:Lymphopenia / Q000150:complications*; D010322:Parvoviridae Infections / Q000150:complications* / Q000821:virology; D016732:Parvovirus B19, Human / Q000235:genetics*