Diagnosis of Genital Warts
Genital warts can typically be diagnosed clinically through visual inspection using bright light and magnification, with biopsy reserved for atypical presentations or treatment failures. 1
Clinical Diagnosis Approach
Visual Examination
- Use bright light and magnification to examine the suspected lesions
- Look for characteristic features:
- Flesh-colored, pink, or hyperpigmented papules
- Rough, irregular surface texture
- Single or multiple lesions on genital skin
- Usually asymptomatic (occasionally pruritic or painful) 1
When to Consider Biopsy
Biopsy is indicated in specific situations:
- Lesions with atypical appearance (pigmented, indurated, fixed, or ulcerated)
- When standard treatments have failed
- In immunocompromised patients
- When there is suspicion for malignancy 1, 2
The FDA label for podofilox specifically states: "Although genital warts have a characteristic appearance, histopathologic confirmation should be obtained if there is any doubt of the diagnosis." 3
Laboratory Testing
- HPV DNA/RNA testing is NOT recommended for routine diagnosis of visible genital warts 2, 1
- The CDC guidelines clearly state that "screening for subclinical genital HPV infection using DNA or RNA tests or acetic acid is not recommended" 2
- The clinical utility of HPV typing for visible genital warts is unclear and should not guide management decisions 1
Acetic Acid Testing
- Routine use of acetic acid soaks with light and magnification is NOT recommended as a screening test 2
- Acetowhitening is not specific for HPV infection and can lead to false positives
- In special situations, experienced clinicians may find this test useful for identification of flat genital warts 2
Differential Diagnosis Considerations
It's important to differentiate genital warts from:
- Squamous cell carcinoma (particularly "Bowenoid papulosis")
- Molluscum contagiosum
- Normal anatomic variants (pearly penile papules, vestibular papillae)
- Condylomata lata (secondary syphilis)
- Seborrheic keratosis 3, 4
Special Considerations
Immunocompromised Patients
- More frequent biopsy may be needed for confirmation of diagnosis
- Squamous cell carcinomas arising in or resembling genital warts might occur more frequently 2
Pregnancy
- Genital warts can proliferate and become friable during pregnancy
- Many experts advocate removal during pregnancy 2
Associated Testing
- Consider screening for other STIs (gonorrhea, chlamydia, syphilis, HIV)
- Female patients with genital warts should be reminded that cytologic screening for cervical cancer is recommended 2, 1
The American Medical Association Consensus Conference confirms that "in most cases, EGWs can be diagnosed clinically by visual inspection" 5, making this the standard first-line approach to diagnosis.
Remember that no swab-based diagnostic test is currently recommended for routine confirmation of genital warts. The definitive diagnosis, when needed, relies on biopsy and histopathologic examination rather than any type of swab test.