Differential Diagnosis for Malodorous Vaginal Discharge in a Pregnant Woman
- Single most likely diagnosis:
- Bacterial Vaginosis (BV): The presence of a thin, gray, malodorous discharge coating the vaginal walls, along with the saline wet mount examination showing numerous epithelial cells coated with bacteria (clue cells), is highly suggestive of BV. The absence of white blood cells, motile organisms, and significant inflammation further supports this diagnosis.
- Other Likely diagnoses:
- Vulvovaginal Candidiasis: Although less likely given the description of the discharge and the absence of erythema or edema, yeast infections can cause a malodorous discharge and are common in pregnant women.
- Trichomoniasis: This sexually transmitted infection can cause a malodorous, thin discharge, but the presence of motile organisms on wet mount (which were not seen in this case) is typically diagnostic.
- Do Not Miss diagnoses:
- Pelvic Inflammatory Disease (PID): Although the patient does not have cervical or adnexal tenderness, PID can present subtly, especially in pregnant women. Missing this diagnosis could lead to serious complications, including infertility and ectopic pregnancy.
- Chorioamnionitis: Infection of the amniotic fluid and placenta, which can be life-threatening for both the mother and the fetus. The presence of a malodorous discharge in a pregnant woman should prompt consideration of this diagnosis, especially if there are signs of preterm labor or fetal distress.
- Rare diagnoses:
- Desquamative Inflammatory Vaginitis (DIV): A rare condition characterized by a purulent vaginal discharge, which could be considered if other diagnoses are ruled out and the patient's symptoms persist.
- Foreign Body: A retained foreign body in the vagina, such as a forgotten tampon, can cause a malodorous discharge. This would be an unusual cause in a pregnant woman but should be considered if the discharge is particularly foul-smelling and other diagnoses are excluded.