Differential Diagnosis for a 17-year-old girl with a nontender, ulcerated vaginal lesion
- Single most likely diagnosis:
- F) Virus: The description of a nontender, ulcerated lesion with raised borders, particularly in a sexually active individual, is highly suggestive of genital herpes, which is caused by the herpes simplex virus (HSV). This condition is common among sexually active individuals and can present with such lesions.
- Other Likely diagnoses:
- E) Spirochete: This refers to syphilis, caused by Treponema pallidum. The primary stage of syphilis can present with a single, painless chancre, which is an ulcerated lesion. Given the patient's sexual history, this is a plausible diagnosis.
- C) Obligate intracellular bacterium: This could refer to Chlamydia trachomatis, which can cause lymphogranuloma venereum (LGV), presenting with genital ulcers among other symptoms. However, the primary presentation of LGV is more commonly associated with painful lymphadenopathy.
- Do Not Miss diagnoses:
- B) Gram-negative diplococcus: Neisseria gonorrhoeae can cause gonococcal infections, which, while less commonly associated with ulcerative lesions, can present in various ways, including cervicitis or urethritis. Missing this diagnosis could lead to complications like pelvic inflammatory disease (PID).
- A) Gram-negative bacillus: While less common, certain Gram-negative bacilli could potentially cause genital infections, though they are not typically the first consideration for ulcerative lesions in this context.
- Rare diagnoses:
- D) Protozoan: Protozoal infections like those caused by Trichomonas vaginalis are more commonly associated with vaginitis and not typically with ulcerative lesions.
- Other rare causes could include granuloma inguinale (caused by Klebsiella granulomatis, a Gram-negative bacillus) or lymphogranuloma venereum (mentioned earlier), though these are less common in many parts of the world and would be considered based on specific risk factors, travel history, or exposure history.