A case of neonatal herpes infection which proved to be a mixed infection of herpes simplex virus type 1 and type 2

: We encountered a case which proved to be a mixed infection of herpes simplex virus (HSV) type 1 and type 2 in retrospective terms by in situ hybridization (ISH) and polymerase chain reaction (PCR). The case was a male. The gestational age was 39 weeks and 2 days. The birth body weight was 3024 g. A fever developed from the age of 6 days and he was admitted to the neonatal intensive care unit at the age of eight days. AST was 1042 IU/L, and ALT 206 IU/L. In spite of treatment, the patient died at the age of 12 days. Using paraffin embedded tissues, we performed the ISH and PCR on the cerebrum, lungs, liver, spleen, bone marrow, adrenal gland, and kidneys. With the ISH, the lungs, liver, spleen and adrenal gland were both HSV type 1 and type 2. With the PCR, only the liver was positive for type 1, and the lungs, liver, spleen, and adrenal gland were positive for type 2. In the ISH, a probe showing a cross reaction between type 1 and type 2 was used for type 1 probe this time. But a type 2 probe and PCR did not show a cross reaction. We concluded that this case confirmed the presence of mixed infection (HSV type 1 and type 2) in neonatal HSV infection.