A case of drug-induced hypersensitivity syndrome-like symptoms following HHV-6 encephalopathy.
BACKGROUND
Drug-induced hypersensitivity syndrome (DIHS) is a rare but severe disorder due to a systemic hypersensitivity reaction. We report on a case with DIHS-like symptoms following human herpes virus 6 (HHV-6) infection complicated with encephalopathy.


METHODS
An 11-month-old girl suffered from a human herpes virus 6 (HHV-6) infection (exanthema subitum) complicated with encephalopathy. We treated the patient with continuous infusion of thiopental, assisted mechanical ventilation, methylprednisolone pulse therapy, and gamma-globulin infusion therapy starting on the fifth day of the illness and started phenobarbital administration on the eleventh day. The patient developed a fever, systemic erythematous exanthema, lymphadenopathy, and eosinophilia two weeks after the start of phenobarbital administration. Steroid therapy, methylprednisolone (4 mg/kg/day) followed by oral prednisolone (1 mg/kg/day), was started on the 28th day and was tapered off on the 72nd day after admission. Serum anti-HHV-6 IgG antibody elevation and the presence of HHV-6 DNA in the peripheral blood detected by polymerase chain reaction (PCR) analysis suggested reactivation of HHV-6 after the primary infection of HHV-6. Lymphocyte transformation test for phenobarbital was positive three weeks after the DIHS crisis.


CONCLUSIONS
HHV-6 reactivation is a unique feature in DIHS. In general one develops DIHS accompanied by reactivation of HHV-6 which has been residing in the body since the initial infection (exanthema subitum) in early childhood. This is the first report of a patient with DIHS-like symptoms which developed immediately following the primary infection of HHV-6.
Saida
Satoshi
S
Department of Pediatrics, Japanese Red Cross Wakayama Medical Center, Wakayama, Japan.
Yoshida
Akira
A
Tanaka
Rieko
R
Abe
Junya
J
Hamahata
Keigo
K
Okumura
Mitsuyoshi
M
Momoi
Toru
T
D000927:Anticonvulsants / Q000008:administration & dosage / Q000009:adverse effects; D001928:Brain Diseases, Metabolic / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology; D003937:Diagnosis, Differential; D004342:Drug Hypersensitivity / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology; D004802:Eosinophilia; D005077:Exanthema Subitum / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology; D005260:Female; D005938:Glucocorticoids / Q000627:therapeutic use; D015654:Herpesvirus 6, Human / Q000472:pathogenicity / Q000502:physiology*; D006801:Humans; D007223:Infant; D008206:Lymphatic Diseases; D010634:Phenobarbital / Q000008:administration & dosage / Q000009:adverse effects; D012640:Seizures; D014775:Virus Activation
D000927:Anticonvulsants; D005938:Glucocorticoids; D010634:Phenobarbital