From the Guidelines
Additional testing for HSV-1 IgG antibodies is not recommended for routine diagnosis, as type-specific serologic tests are generally sufficient for detecting past infection. The presence of HSV-1 IgG antibodies indicates past infection with herpes simplex virus type 1, which typically remains in your body for life 1. If a patient receives an equivocal or uncertain result, a repeat test in 4-6 weeks may be warranted to see if antibody levels have changed.
Key Considerations
- In cases where confirmation is critical, the Western blot test is considered the gold standard, though it's rarely needed in clinical practice 1.
- If a patient is experiencing symptoms but has a negative HSV-1 IgG test, direct testing of lesions through PCR or viral culture would be more appropriate than repeating the antibody test 1.
- It's essential to note that HSV-1 IgG tests only indicate past infection and cannot determine when the patient was infected, the location of infection (oral or genital), or whether they'll experience symptoms 1.
Testing Limitations
- The sensitivity of HSV-1 serologic testing can be limited, with one study showing a sensitivity of 70.2% 1.
- The specificity of HSV-2 serologic tests can also be a concern, with one study showing a specificity of 57.4% 1.
Clinical Implications
- Most people with HSV-1 antibodies have oral herpes, though genital HSV-1 infections are becoming more common 1.
- The diagnosis and management of genital herpes should be based on the optimal tests for HSV-1 or HSV-2 detection from a genital ulcer/lesion/suspected HSV outbreak, which includes nucleic acid amplification test (NAAT)/polymerase chain reaction (PCR) diagnostic assays 1.
From the Research
Additional Tests for HSV 1 IgG Antibody
- The diagnosis of genital herpes can be confirmed using type-specific serology tests that detect antibodies to HSV glycoproteins G-1 and G-2 2.
- These tests can distinguish between HSV-1 and HSV-2 infections and can be used to identify asymptomatic carriers and persons at risk for acquiring HSV 2.
- However, the detection of HSV-1 IgG antibody may not be useful for diagnosis in patients with genital ulcer disease, as it has poor specificity, positive predictive value, and sensitivity compared to PCR results 3.
- On the other hand, HSV-2 IgG detection can help strengthen the diagnosis of recurrent HSV-2 disease, while the absence of HSV-2 IgG antibody can help exclude genital herpes as a likely cause of recurrent genital ulceration 3.
- Several commercial tests are available for serological testing of HSV-1 and HSV-2, including the HerpeSelect-1 and HerpeSelect-2 enzyme-linked immunosorbent assay tests and the HSV-1 and HSV-2 HerpeSelect1/2 Immunoblot 2.
- Nucleic acid amplification tests, such as PCR, have high sensitivities and specificities for the diagnosis of symptomatic HSV-1 and HSV-2 4.
- Effective STI prevention interventions include screening, contact tracing of sexual partners, and promoting effective barrier contraception 4.