A Comparison of Enzyme Immunoassay and Polymerase Chain Reaction with the Clinical Examination for Diagnosing Ocular Herpetic Disease

Purpose: The results of two laboratory diagnostic herpes simplex virus (HSV) tests, an enzyme immunoassay (improved Herpchek [iHC]) and the polymerase chain reaction (PCR), were compared with the clinical examination in the diagnosis of HSV. We determined when diagnostic laboratory tests provided the initial diagnosis of HSV ocular disease and when they were only confirmatory. Methods: The sensitivity and specificity of iHC and PCR were determined using 22 HSV culture-positive clinical samples, 10 adenovirus culture-positive clinical samples, 5 samples from normal conjunctivas, 4 bacterial samples, and 1 sample containing Varicella zostervirus. The medical history of the 22 patients with positive HSV cultures were reviewed to determine the initial diagnosis by clinical examination and the initial therapy. Results: For typical presentations of ocular HSV disease, the clinical examination is as accurate as iHC (P = 0.99) and PCR (P = 0.24). However, for atypical presentations of ocular HSV disease, iHC (P = 0.000005) or PCR (P = 0.00006) were more accurate in detecting HSV infection than the clinical examination. Conclusion: Laboratory diagnosis of HSV from ocular samples was most useful to the clinician in atypical presentations of herpetic ocular disease.