Background Type specific serologic tests for herpes simplex virus (HSV)-1&2 are used for sero-epidemiological studies. Its early application has also been shown to be of benefit in testing for primary & recurrent infections in diagnosis and patient management. The present study was conducted to evaluate the role of type specific HSV-1&2 antibody detection as a diagnostic modality in patients with clinically suspected genital herpes.

Methods Sera obtained from 44 patients with clinically suspected genital herpes attending the STD clinic of our institution over last 7 months were tested for type specific HSV-1&2 IgG antibody by glycoprotein G based ELISA (HerpeSelect 1&2, Focus Diagnostics, USA). Direct Fluorescent Antibody testing (DFA) (BIO-RAD laboratories, USA) was used for identification and typing of HSV-1& 2 in genital ulcer specimens in all cases.

Results There were 21 cases of primary & 23 cases of recurrent genital ulceration. DFA was positive in 68% samples (43% only HSV-2, 9% only HSV-1, 16% both HSV-1&2). On comparison with DFA, the sensitivity, specificity, positive and negative predictive value of HSV-2 IgG ELISA in primary herpetic ulcer was 8%, 75%, 33%, 33%, while it was 79%, 89%, 92%, 73% in recurrent genital ulceration. The sensitivity, specificity, positive predictive and negative predictive values of HSV-1 IgG ELISA in primary herpetic ulcer was 50%, 67%, 37.5%, 77%, while it was 80%, 39%, 27%, and 87.5% in recurrent genital ulceration.

Conclusion Our results highlight the importance of HSV-2 IgG detection in strengthening the diagnosis of recurrent HSV-2 disease, while absence of HSV-2 IgG antibody helps in excluding genital herpes as a likely cause of recurrent genital ulceration. The identification of HSV-1 IgG antibody may not be useful for diagnosis in patients of genital ulcer disease highlighting the need for typing HSV-1 strains from the genital lesion.