A 25-year-old woman comes to the office for evaluation of increasing amounts of malodorous vaginal discharge over the past 4 days. The patient has no postcoital spotting or intermenstrual bleeding. Her last menstrual period was 3 weeks ago. She has been sexually active with a new partner for the past month and they use condoms intermittently. She has no chronic medical conditions or previous surgeries. The patient takes no daily medications. She has a history of chlamydial cervicitis at age 19. Vitals signs are normal. Physical examination shows no vulvar or vaginal erythema or lesions. There is an off-white discharge throughout the vaginal vault with no discharge from the cervical os. The uterus is mobile and nontender with no adnexal masses. Which of the following is the most likely diagnosis?
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Bacterial vaginosis (BV) is a common cause of vaginal discharge and occurs due to an imbalance in vaginal flora. In patients with BV, the physiologic lactobacilli colonization of the vagina decreases, leading to an increased pH and overgrowth of anaerobic bacteria (eg, Gardnerella vaginalis). The increased pH and bacterial overgrowth lead to increasing malodorous vaginal discharge. Risk factors for BV include women having sex with women, douching, and using tobacco.
Patients with BV typically have a malodorous, thin, off-white vaginal discharge with associated no vulvovaginal inflammation (eg, pruritus, erythema). Therefore, patients have no vulvar erythema, cervical discharge, or friability. Evaluation of vaginal discharge reveals a pH >4.5, an amine odor with the addition of potassium hydroxide (whiff test), and clue cells on microscopy (eg, Amsel criteria). Treatment is with metronidazole or clindamycin.
(Choice A) Acute cervicitis, due to Neisseria gonorrhoeae and Chlamydia trachomatis, presents with postcoital or intermenstrual bleeding. Physical examination reveals mucopurulent cervical discharge and a friable cervix, which are not seen in this patient.
(Choice C) Patients using condoms for contraception may have a latex allergy. The typical presentation is a pruritic, erythematous, vesicular rash at the area of contact. There is no associated malodorous vaginal discharge, making this diagnosis unlikely.
(Choice D) Physiologic leukorrhea is a white, odorless discharge that typically occurs midcycle and resolves spontaneously.
(Choice E) Seminal plasma allergy typically presents with systemic anaphylaxis, although primarily local symptoms may also occur. With local reactions, symptoms include vulvovaginal pruritus and edema. In addition, symptoms are typically associated with recent sexual activity, and condom use is protective.
(Choice F) Trichomonas vaginitis presents with a malodorous, yellow-green vaginal discharge and vaginal erythema on examination. In some cases, punctate hemorrhages may be visualized on the cervix (eg, "strawberry cervix").
(Choice G) Vaginal candidiasis presents with a thick, white discharge and vaginal pruritus; vulvar erythema and excoriations are typically present on examination.
Educational objective:
Bacterial vaginosis typically presents with malodorous, thin, white vaginal discharge in the absence of vulvovaginal inflammation. It is characterized by a vaginal pH >4.5, a positive whiff test, and clue cells on microscopic examination.