[Three cases of herpes simplex virus type 2 myelitis--detection of HSV2 DNA in cerebrospinal fluid]

Polymerase chain reaction (PCR) technique has been successfully used to detect herpes simplex virus (HSV) from patients with HSV encephalitis. By PCR assay capable of differentiating HSV1 and 2, we detected HSV 2 DNA in cerebrospinal fluid (CSF) from patients with HSV myelitis and discussed the clinical findings. Three cases of HSV myelitis (a 49-year-old female, two 38- and 44-year-old males) were studied. All cases were characterized by transverse myelopathy of the thoracic cord, and two patients had recurrence. In all cases HSV1 antibodies were significantly elevated in serum and CSF. We used 500 microliters of CSF for PCR, and prepared one common upstream primer and two type specific downstream primers for HSV1 and HSV2. Using three primers simultaneously different sizes of PCR products were amplified from HSV1 and HSV2 DNA. PCR products subjected to electrophoresis on 1.2% agarose and stained with ethidium bromide. Still more southern blot hybridization was performed to detect DNA by 35S-end-labelled oligonucleotide prove. HSV2 DNA was amplified from CSF in all cases by PCR, and HSV2 DNA was detected at both first and second episode in two relapsing myelitis. No case of relapsing myelitis by HSV2 has been reported. The PCR technique is useful for diagnosis of HSV1 and 2 myelitis, and its would suggest that some patients of idiopathic myelopathy could be due to HSV2 myelitis and HSV2 myelitis may not be rare.