Genital herpes is an STD caused by the human herpes virus type 1 or 2. It causes ulcerative lesions in the genitals. The diagnosis is clinical, with laboratory confirmation by isolating the virus from cell culture, polymerase chain reaction, or serological studies. Treatment consists of antiviral drugs.
- Inoculation for culture and polymerase chain reaction (PCR)
- Serological testing
- The diagnosis of genital herpes is often based on the presence of characteristic lesions; groups of vesicles or ulcers on an erythematous basis are uncommon for genital ulcers, except those caused by the herpes simplex virus. However, these lesions are absent in many patients.
If the diagnosis is unclear, tests to detect HSV are necessary.
The examination usually takes a sample of fluid from the base of the vesicle or from a recent lesion, if present. The absence of HSV during cultivation, especially in patients without active lesions, does not exclude HSV infection, since the isolation of the virus is not constant. In addition, the virological method has limited sensitivity; PCR is more sensitive and used more frequently.
Direct immunofluorescence with labeled monoclonal antibodies is sometimes available; this method is highly specific but not very sensitive.
Serological tests are capable of detecting with great accuracy antibodies to HSV-1 and HSV-2, which develop during the first few weeks after infection and are then constantly present in the body. Thus, if genital herpes infection is believed to be recent, tests may need to be repeated to allow time for seroconversion to occur.
Serologic tests for HSV serve several purposes:
- Evaluation of patients who do not have suspicious genital lesions, but for whom this examination is necessary or they themselves wish to undergo it (for example, due to genital lesions that have occurred in the past or high-risk behavior)
- To help determine the risk of developing focal lesions
- Identification of pregnant women who do not have genital lesions but are at risk of transmitting herpes to their newborn during childbirth
- Determination of the risk of infection of a healthy partner from a sexual partner with an existing genital herpes