Validity of Patient-Collected Wet Mounts

Overview

Purpose/Objectives: To compare wet mount findings for clue cells, yeast, trichomonads and white blood cells per high-power field in self-collected vaginal specimens, compared to clinician-collected specimens, among symptomatic women visiting the San Antonio Metropolitan Health sexually transmitted disease clinic. Research Design/Plan: Prospective, non-randomized, non-blinded trial Methods: Obtain informed consent and specimens from 40 symptomatic adult females (eg abnormal discharge, odor and/or itching). Calculate concordance between clinician- and patient-collected samples using a Wilcoxon Matched-Pair test. Calculate sensitivity, specificity, positive predictive value and negative predictive value of the patient-collected wet mount, using the clinician-collected specimens as the "gold standard." Clinical Relevance: A "wet mount," or microscopic examination, is commonly used to diagnose trichomoniasis and yeast in females, and constitutes one diagnostic element for bacterial vaginosis. While patient-collected vaginal swabs are acceptable for nucleic acid probe tests for chlamydia and gonorrhea and nucleic acid probe tests for trichomoniasis little information about patient-collected wet mounts exists in the literature. Self-collection by women before being seen by a clinician can increase the speed and efficiency of the visit. The method is highly acceptable to women. In the investigators' clinic, women routinely collect their own gonorrhea and chlamydia swabs, so adding an additional swab would not be burdensome.

Studies have shown that self-collection of vaginal swabs is highly acceptable to women. Studies have also shown that patient-collected vaginal swabs are acceptable for nucleic acid probe tests for chlamydia and gonorrhea and nucleic acid probe tests for trichomoniasis; however, little information about patient-collected wet mounts exists in the literature. The investigators' goal is to compare wet mount findings for clue cells, yeast, trichomonads and white blood cells per high-power field in self-collected vaginal specimens, compared to clinician-collected specimens, among symptomatic women visiting the San Antonio Metropolitan Health sexually transmitted disease clinic. Self-collection by women before being seen by a clinician can increase the speed and efficiency of the visit. In the investigators' clinic, women routinely collect their own gonorrhea and chlamydia swabs, so adding an additional swab would not be burdensome. Based on the reliability of patient-collected swabs for nucleic amplification tests, it is expected that patient-collected wet mounts could be as valid as conventionally collected samples. Step-by-Step Methods: Potential study participants as described above will be approached by research staff while in the waiting area. If a patient provides informed consent, she will self-collect a wet mount specimen by inserting a cotton-tip swab in the vagina about 2 inches and rotating for 10-30 seconds; later, her clinician will collect a second specimen from the vaginal fornix and place it in a red-top tube with a small amount of normal saline. The clinician-collected sample will be labeled with the patient's identifying information and processed in the usual way by laboratory staff, with results recorded in electronic medical records. The patient-collected sample will be identified by a number only, and results recorded in a study log. The study is complete when the results of 40 patient- and clinician-collected swabs are recorded. Data Analysis Plan: Concordance between clinician- and patient-collected samples will be calculated using a Wilcoxon Matched-Pair test. Sensitivity, specificity, positive predictive value and negative predictive value of the patient-collected wet mount will also be calculated, using the clinician-collected specimens as the "gold standard."