The rapid diagnosis of infection is becoming increasingly important to improving the effectiveness of subsequent treatment. Vaginal infection (“vaginitis”), for example, exists in three primary forms, i.e., bacterial vaginosis, candidal vaginitis (“yeast”), and trichomonas vaginitis (“trich”). Various techniques have been developed in an attempt to rapidly diagnose individual forms of vaginitis. Bacterial vaginosis, for example, has been diagnosed using “clue cells” (vaginal epithelial cells with adherent surface bacteria). However, conventional techniques for confirming the presence of “clue cells” are often complicated and slow. Techniques have been utilized that detect an elevated pH level in an infected sample.
Bacterial vaginosis and trichomonas vaginitis (primarily caused by the protozoan, Trichomonas vaginalis) may also cause a “fishy” odor that stems from an elevated level of amines, such as putrescine (1,4-diaminobutane), cadaverine (1,5-diamino pentane), trimethylamine, etc., in an infected vaginal sample. In bacterial vaginosis, for instance, amines are believed to be produced by members of anaerobic bacteria, prevotella, bacteroides, mobiluncus, and peptococcus. One conventional test for detecting the presence of amines in a vaginal test sample is known as the “Whiff test”, which involves adding a strong alkali to a sample to form an enhanced odor. Unfortunately, such tests are undesired in that they require performance by a professional and utilize caustic chemicals. Another conventional technique for detecting amines in a sample is described in U.S. Pat. No. 5,124,254 to Hewlins, et al. Hewlins, et al. uses a diamine oxidase that reacts with diamines, such as putrescine and cadaverine, to give hydrogen peroxide. The hydroxen peroxide is then detected by a chromogenic system.
Various attempts at diagnosing candidal vaginitis, which is primarily caused by the presence of the yeast, Candida albicans, have also been developed. One such method involves detecting the presence of enzymes thought to act as a virulence factor for Candida albicans, such as proteases (e.g., aspartic protease) and/or peptidases (e.g., metallopeptidases). For example, U.S. Pat. No. 5,585,273 to Lawrence, et al. describes an enzyme assay for detecting Candida albicans aspartic protease. In Lawrence, et al., a sample, e.g., vaginal fluid, is contacted with a solid support having a reporter enzyme immobilized thereon. The reporter enzyme is releasable from the solid support upon action of an enzymatically active aspartic protease. After contacting the solid support, the sample is combined with an indicator susceptible to a visible or detectable change upon action of the reporter enzyme. If the indicator undergoes a detectable change, enzymatically active aspartic protease is present.
Unfortunately, the techniques described above suffer from significant disadvantages. One significant disadvantage is that many conventional techniques are unable to detect multiple forms of infection in a single test sample. In addition, many conventional techniques are too slow, costly, and complex for ordinary consumer use. As such, a need currently exists for a technique for detecting multiple forms of infection in a single test sample, which is fast, inexpensive, and easy to use.