Comparison of detection of varicella-zoster virus by the Tzanck smear, direct immunofluorescence with a monoclonal antibody, and virus isolation.

A study comparing direct immunofluorescence assay using a new monoclonal antibody specific for a varicella-zoster virus glycoprotein complex, the Tzanck smear, and virus isolation for detection of varicella-zoster virus in 56 patients with clinically apparent herpes zoster is presented. Of 47 patients with clinical herpes zoster and with cultures negative for herpes simplex virus, 30 (64%) had positive Tzanck smears, direct immunofluorescence assay results were positive in 26 (55%), and cultures were positive in only 12 (26%). Both direct immunofluorescence assay and the Tzanck smear were found to be superior to culture technics; however, direct immunofluorescence assay was found to have greater specificity.