An immunocompetent child with chromosomally integrated human herpesvirus 6B accidentally identified during the care of Mycoplasma pneumoniae infection.
Human herpesvirus 6 (HHV-6) is the only virus known to integrate into human chromosomes and be transmitted from parents to offspring. Less than 1% of the population carries integrated HHV-6 in their genomes. Here, we report the case of a 9-year-old Japanese girl with an extraordinarily high copy number of HHV-6B in her genome. The integrated virus genome was detected by real-time polymerase chain reaction (PCR) in cerebrospinal fluid and serum during the treatment of meningoencephalitis and pneumonia caused by Mycoplasma pneumoniae infection. Furthermore, the HHV-6B genome was detected in hair follicle, plasma, and whole blood in the patient and her mother, but not in the patient's father. Fluorescence in situ hybridization revealed that the viral genome was integrated into chromosome 22. Therefore, these results emphasize the importance of screening for chromosomally integrated HHV-6 prior to starting unnecessary antiviral therapies, particularly for patients harboring HHV-6 with a high copy number.
Department of Pediatrics, Chiba University School of Medicine, Chiba, Japan. Electronic address: oikawa@chiba-u.jp.
Junko
J
Oikawa
Department of Pediatrics, Chiba University School of Medicine, Chiba, Japan.
Junko
J
Tanaka
Department of Pediatrics, Fujita Health University School of Medicine, Aichi, Japan.
Tetsushi
T
Yoshikawa
Department of Pediatrics, Chiba University School of Medicine, Chiba, Japan.
Yoshinori
Y
Morita
Department of Pediatrics, Chiba University School of Medicine, Chiba, Japan.
Haruka
H
Hishiki
Division of Control and Treatment of Infectious Diseases, Chiba University Hospital, Chiba, Japan.
Naruhiko
N
Ishiwada
Division of Molecular Genetics, Institute for Comprehensive Medical Science, Fujita Health University School of Medicine, Aichi, Japan.
Tamae
T
Ohye
Division of Molecular Genetics, Institute for Comprehensive Medical Science, Fujita Health University School of Medicine, Aichi, Japan.
Hiroki
H
Kurahashi
Department of Pediatrics, Chiba University School of Medicine, Chiba, Japan.
Yoichi
Y
Kohno
D002648:Child; D002877:Chromosomes, Human / Q000235:genetics* / Q000821:virology*; D005260:Female; D015654:Herpesvirus 6, Human / Q000235:genetics*; D006801:Humans; D007121:Immunocompetence; D018445:Infectious Disease Transmission, Vertical; D009175:Mycoplasma Infections / Q000821:virology*; D009177:Mycoplasma pneumoniae; D016662:Virus Integration / Q000235:genetics*
Chromosomally integrated human herpesvirus 6; FISH; Real-time PCR; ciHHV-6