Evaluation of three immunofluorescence assays for culture confirmation and typing of herpes simplex virus.

Three pairs of monoclonal antibodies, supplied in kits by Electro-Nucleonics, Inc. (ENI), The Syva Co., and Kallestad Laboratories, Inc. (KL), were evaluated for the laboratory confirmation and typing of herpes simplex virus (HSV). Of 108 coded HSV slide preparation, run in parallel with each monoclonal-antibody set, 103 were equivalent by the immunofluorescence assays. Among the five discordant isolates, three (2.8%) did not type with the KL monoclonal antibodies and two (1.9%) false-positive results occurred with the Syva typing system. All of the HSV clinical isolates tested were correctly typed with the ENI indirect immunofluorescence antigen detection system. Typing confirmation of the five discordant HSV isolates was performed by differential sensitivity to 5-bromo-2'-deoxyuridine and endonuclease cleavage analysis of the viral DNA. Use of the Syva and KL direct immunofluorescence antigen detection systems for the identification of HSV isolates is less time-consuming than use of the ENI indirect antigen detection system; however, sensitivity and specificity may be lost.