The value of detecting anti-VZV IgG antibody in CSF to diagnose VZV vasculopathy

Background: Factors that may obscure the diagnosis of varicella zoster virus (VZV) vasculopathy include the absence of rash before TIAs or stroke as well as similar clinical features and imaging, angiographic, and CSF abnormalities to those of other vasculopathies. Diagnosis relies on virologic confirmation that detects VZV DNA, anti-VZV IgG antibody, or both in the CSF. Methods: We reviewed our current 14 cases of patients diagnosed with VZV vasculopathy based on combined clinical, imaging, angiographic, or CSF abnormalities. All CSFs must have been tested for VZV DNA by PCR and for anti-VZV IgG antibody by enzyme immunoassay and found to be positive for either or both. Of the 14 subjects, 8 had a history of recent zoster, whereas 6 had no history of zoster rash before developing vasculopathy. Results: All 14 subjects (100%) had anti-VZV IgG antibody in their CSF, whereas only 4 (28%) had VZV DNA. The detection of anti-VZV IgG antibody in CSF was a more sensitive indicator of VZV vasculopathy than detection of VZV DNA (p < 0.001). Conclusions: In varicella zoster virus (VZV) vasculopathy, the diagnostic value of detecting anti-VZV IgG antibody in CSF is greater than that of detecting VZV DNA. Although a positive PCR for VZV DNA in CSF is helpful, a negative PCR does not exclude the diagnosis of VZV vasculopathy. Only when the CSF is negative for both VZV DNA and anti-VZV IgG antibody can the diagnosis of VZV vasculopathy be excluded.