In a recent statement, the FDA reminded health care providers and clinical laboratory staff about the risk of false positive genital herpes simplex virus type 2 (HSV-2) serological test results.1
Takeaways
- The FDA has warned health care providers and clinical laboratory staff about the potential for false positive results in HSV-2 serological tests.
- CDC guidelines should be consulted before ordering HSV-2 serological tests, and healthcare providers should be cautious when interpreting results, especially in patients with a low risk of infection or those near the cutoff point.
- Clinical diagnosis of genital herpes can be challenging, with increased risks of false results for patients with low infection risk, recent blood tests, or results close to the test's cutoff value.
- While patients with genital symptoms should undergo HSV-2 testing, asymptomatic patients with a low risk of infection are generally advised against serological testing because of the heightened risk of inaccurate results.
- Reporting false positive HSV-2 test results to the FDA is crucial for improving the understanding and management of associated risks. This can be done voluntarily through the MedWatch program.
To reduce the risk of a false positive HSV-2 serological test result, the FDA provided information on risk factors and recommendations for health care providers and clinical laboratory staff. Additionally, the FDA has stated it will provide new information as it becomes available.
According to the FDA, health care providers and clinical laboratory staff should review CDC guidelines prior to ordering HSV-2 serological testing and to be aware of the chances for a false positive result. Providers should also counsel patients about testing limitations before testing, and results should undergo performative testing in accordance with professional guidelines.
There are difficulties in clinically diagnosing genital herpes, according to the CDC. Patients with a low risk of infection, receiving a blood test near infection, and with test results near the cutoff are at an increased risk of a false result.
According to the CDC, patients with genital symptoms should receive HSV-2 testing to confirm if they have the condition.2 Most patients without symptoms should not receive an HSV-2 serological test because of the increased risk of a wrong test result in individuals with a low risk of infection.
Herpes tests are not as accurate as tests for other sexually transmitted infections such as chlamydia and gonorrhea, increasing the risk of false positive results.Blood tests may be useful in patients with genital symptoms related to herpes, previous or current sex with a partner with genital herpes, or signs of herpes identified by a provider.
False positive HSV-2 serological test results should be reported to the FDA.1 Voluntary reports can be submitted through MedWatch, the FDA Safety Information and Adverse Event Reporting program.
Health care personnel and clinical laboratory staff of facilities following the FDA's user facility reporting requirements should comply with established procedures.Reporting adverse events improves the FDA’s identification and understanding of risks associated with medical devices.
Reference
- HSV-2 tests for genital herpes can produce false reactive results - Letter to clinical laboratory staff and health care providers. US Food and Drug Administration. December 27, 2023. Accessed January 2, 2023. https://www.fda.gov/medical-devices/letters-health-care-providers/hsv-2-tests-genital-herpes-can-produce-false-reactive-results-letter-clinical-laboratory-staff-and?utm_medium=email&utm_source=govdelivery
- Genital herpes screening FAQ. Centers for Disease Control and Prevention. Accessed January 2, 2023. https://www.cdc.gov/std/herpes/screening.htm
