WBR0786

Author	[[PageAuthor::Serge Korjian M.D. (Reviewed by Serge Korjian and Yazan Daaboul, M.D.)]]
Exam Type	ExamType::USMLE Step 1
Main Category	MainCategory::Microbiology
Sub Category	SubCategory::Reproductive
Prompt	[[Prompt::A 33-year-old woman presents to the gynecology clinic for 2 weeks of vaginal itching and burning. She reports first noticing a greenish vaginal discharge 1 week ago associated with a very foul smell that did not seem to resolve completely after showers. The patient denies any previous episodes. She admits to having several sexual partners and to using barrier protection infrequently. What is the most likely finding on wet mount of a vaginal swab in this patient?]]
Answer A	AnswerA::Clue cells
Answer A Explanation	AnswerAExp::Clue cells are usually observed in bacterial vaginosis. They are associated with the organism ''Gardnerella vaginalis'', which clinically manifests with greyish vaginal discharge and a positive whiff test.
Answer B	AnswerB::Motile trophozoites
Answer B Explanation	AnswerBExp::Motile trophozoites are characteristic of ''Trichomonas vaginalis''. Patients typically present with malodorous greenish vaginal discharge associated with vaginal itching and burning.
Answer C	AnswerC::Amastigotes
Answer C Explanation	AnswerCExp::Amastigotes are are usually not seen on vaginal swabs. They are seen on the blood smear of patients with leishmaniasis.
Answer D	AnswerD::Mold hyphae
Answer D Explanation	AnswerDExp::Pseudohyphae are seen in patients with candida infections.
Answer E	AnswerE::Bacterial spores
Answer E Explanation	AnswerEExp::Bacterial spores are usually not seen on vaginal swabs.
Right Answer	RightAnswer::B
Explanation	[[Explanation::Trichomonas vaginalis is an anaerobic protozoan and the the causative agent of trichomoniasis, one of the most common sexually transmitted infections. As the organism only has trophozoites and no cysts, transmission occurs directly. Trichomonas usually infects the urogenital tract causing vaginitis in women and urethritis in men. A frothy thick green vaginal discharge can be observed and is typically very malodorous. Diagnosis is usually by detecting motile trophozoites on vaginal wet-mount. Treatment is with metronidazole for both partners to prevent reinfection. Educational Objective: Patients with Trichomonas vaginalis vaginal infection typically present with malodorous greenish vaginal discharge associated with vaginal itching and burning. Diagnosis of trichomoniasis is usually by detection of motile trophozoites on vaginal swab. References: Schwebke JR, Burgess D. Trichomoniasis. Clin Microbiol Rev. 2004;17(4):794-803.]]
Approved	Approved::Yes
Keyword	WBRKeyword::Trophozoites, WBRKeyword::Trichomonas vaginalis, WBRKeyword::Sexually transmitted infections, WBRKeyword::Sexually transmitted disease, WBRKeyword::STI, WBRKeyword::STD, WBRKeyword::Wet mount, WBRKeyword::Vaginal swab
Linked Question	Linked::
Order in Linked Questions	LinkedOrder::