Human herpesvirus 6 in lung tissue from patients with pneumonitis after bone marrow transplantation.
BACKGROUND
Human herpesvirus 6 (HHV-6) is a recently described herpesvirus that is epidemiologically and biologically similar to cytomegalovirus. It is the cause of exanthem subitum (roseola) in children.


METHODS
To evaluate the possible role of HHV-6 infection in pneumonitis in immunocompromised patients, we used quantitative HHV-6 polymerase chain reactions to study lung-biopsy specimens from 15 patients with pneumonitis after bone marrow transplantation and lung tissue from 15 immunocompetent subjects without pneumonitis and 6 fetuses.


RESULTS
HHV-6 DNA was detected in lung tissue from all 15 patients, from 14 seropositive control subjects, and from none of the 7 seronegative control subjects. Six patients had levels of HHV-6 DNA in lung tissue that were 10 to 500 times higher than those in any of the other patients or control subjects. Increased levels of HHV-6 DNA correlated with a decreased risk of death from pneumonitis (P = 0.015), an increased severity of graft-versus-host disease (P = 0.023), and the presence of idiopathic pneumonitis (P = 0.037). Levels of HHV-6 DNA correlated directly with the changes in HHV-6 antibody titers in the interval between the pretransplantation period and the open-lung biopsy (P = 0.002). Low levels of HHV-6 antibody at the time of the open-lung biopsy were also associated with the diagnosis of idiopathic pneumonitis (P = 0.002).


CONCLUSIONS
The concentrations of HHV-6 genome in lung tissue and their relation to changes in serologic titers support an association between HHV-6 infection and idiopathic pneumonitis in immunocompromised hosts.
Department of Laboratory Medicine, University of Washington, Seattle.
R W
RW
Cone
R C
RC
Hackman
M L
ML
Huang
R A
RA
Bowden
J D
JD
Meyers
M
M
Metcalf
J
J
Zeh
R
R
Ashley
L
L
Corey
D000293:Adolescent; D000328:Adult; D000914:Antibodies, Viral / Q000032:analysis; D016026:Bone Marrow Transplantation; D002648:Child; D002675:Child, Preschool; D004279:DNA, Viral / Q000032:analysis; D005260:Female; D006566:Herpesviridae Infections / Q000382:microbiology* / Q000473:pathology; D015654:Herpesvirus 6, Human / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D006801:Humans; D008168:Lung / Q000276:immunology / Q000382:microbiology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011014:Pneumonia / Q000382:microbiology* / Q000473:pathology; D016133:Polymerase Chain Reaction; D012189:Retrospective Studies
D000914:Antibodies, Viral; D004279:DNA, Viral