Differential Diagnosis for Postcoital Bleeding
- Single most likely diagnosis
- Trichomoniasis: Justification - The presence of a thin, malodorous vaginal discharge, erythema of the vulva and vaginal mucosa, and the finding of motile, ovoid-shaped organisms on wet mount microscopy are highly suggestive of trichomoniasis, a sexually transmitted infection caused by the protozoan Trichomonas vaginalis. The patient's history of multiple new sexual partners and inconsistent condom use further supports this diagnosis.
- Other Likely diagnoses
- Chlamydia: Justification - Given the patient's history of new sexual partners and inconsistent condom use, chlamydia is a likely consideration. Chlamydia can cause cervicitis, which might explain the erythematous cervix and the presence of macular lesions that bleed easily.
- Gonorrhea: Justification - Similar to chlamydia, gonorrhea is another sexually transmitted infection that could cause cervicitis and postcoital bleeding, especially in someone with a history of multiple sexual partners and inconsistent condom use.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Cervical Cancer: Justification - Although less likely given the patient's age and the acute presentation, cervical cancer can cause postcoital bleeding. It is crucial to not miss this diagnosis, as it requires prompt and specific treatment. The presence of multiple macular lesions on the cervix that bleed easily warrants further investigation, including a possible colposcopy and biopsy.
- Pelvic Inflammatory Disease (PID): Justification - PID is a serious condition that can result from untreated sexually transmitted infections. It can cause significant morbidity and potential long-term fertility issues if not promptly treated. The patient's symptoms of pelvic discomfort and the findings on pelvic examination could be indicative of PID.
- Rare diagnoses
- Vulvar or Vaginal Cancer: Justification - These are rare conditions, especially in a young woman. However, any unusual or persistent vaginal bleeding, especially if accompanied by other symptoms like a mass or significant pain, should prompt an investigation into these possibilities.
- Foreign Body in the Vagina: Justification - Although rare, a foreign body in the vagina could cause local irritation, discharge, and bleeding. This would be more likely if the patient reported inserting objects into her vagina or if such an object was found during the examination.