Sequential measurement of human herpesvirus 6 DNA with polymerase chain reaction method in pediatric living-related liver transplantation.
BACKGROUND
Human herpesvirus 6 (HHV-6), a causative virus of exanthem subitum, may occasionally present with a severe clinical form in immunosuppressed patients after transplantation. In this study, HHV-6 DNA was sequentially measured with a polymerase chain reaction (PCR) method, a quick and sensitive modality in pediatric living-related liver transplantation (LTx).


METHODS
Subjects consisted of 5 post-operative biliary atresia patients undergoing living-related LTx at ages from 8 months to 4 yr. Immunosuppression was performed with Tacrolimus (blood trough level 8-18 within 1 month and 5-10 ng/mL thereafter) and low-dose steroid. Specimens were peripheral blood mononuclear cells (PBMC), plasma, and liver biopsy tissue. The amount of HHV-6 DNA was semiquantified as follows: 1+, 1-10; 2+, 10-100; 3+, 100-1000; 4+, over 1000 copies/105 PBMCs.


RESULTS
A total of 69 blood samples and three liver biopsies were provided for the examination. HHV-6 DNA in PBMC was positive in 2 donors and 3 recipients before LTx. Two patients with negative DNA were converted to 3+ at 2-3 wk after LTx and 3 with positive DNA remained 2+ to 3+ throughout the post-LTx period. Only 1 patient developed clinical symptoms, such as fever, liver dysfunction, petechiae, idiopathic thrombocytopenic purpura, and finally bone marrow suppression. HHV-6 DNA in the liver biopsy tissue and plasma in this patient were 4+ and 2+, respectively.


CONCLUSIONS
HHV-6 DNA in PBMC measured by the PCR method may be persistently high in pediatric recipients after living-related LTx. Although HHV-6 DNA in PBMC may be positive in case of evident infection, positivity in PBMC may not be always associated with the clinical symptoms.
Hasegawa
T
T
Department of Pediatric Surgery, Osaka University, Medical School, Osaka, Japan.
Kimura
T
T
Sasaki
T
T
Okada
A
A
Tanaka-Taya
K
K
Miyagawa
H
H
Amou
K
K
Mushiake
S
S
Yamanishi
K
K
Ishikawa
S
S
D004279:DNA, Viral / Q000302:isolation & purification*; D005077:Exanthema Subitum / Q000175:diagnosis; D006566:Herpesviridae Infections / Q000175:diagnosis*; D015654:Herpesvirus 6, Human / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D007223:Infant; D016031:Liver Transplantation; D019520:Living Donors; D016133:Polymerase Chain Reaction; D011446:Prospective Studies
D004279:DNA, Viral; D007166:Immunosuppressive Agents