Detection of herpes simplex virus DNA in human tear film by the polymerase chain reaction.

We investigated the use of the polymerase chain reaction for detecting genomes of herpes simplex virus, varicella-zoster virus, and cytomegalovirus from tear film of patients with clinically diagnosed herpes simplex virus keratitis. Using the polymerase chain reaction with a herpes simplex virus detection sensitivity adjusted to 1.0 plaque-forming units/ml, we detected herpes simplex virus genomic sequences in 12 of 12 epithelial keratitis specimens, two of six stromal keratitis specimens, but in none of 20 normal specimens. Neither varicella-zoster virus nor cytomegalovirus genomic sequences were detected in any sample. These results suggest that polymerase chain reaction quickly performed with reduced sensitivity is useful as a diagnostic tool for confirming clinical observations.