Exams and Tests

For healthy people, most physicians can diagnose a candidal infection without laboratory tests. Occasionally, if the infection will not go away or involves the entire body, more extensive tests may need to be performed.

• The only definitive way to diagnose a vaginal yeast infection is to complete a full gynecologic exam.
  
  
  • This exam includes using a specialized instrument (speculum) to hold open the vagina. The exam can be uncomfortable because of pressure against the tissues. The doctor takes a swab of the discharge and may obtain other cultures to rule out other diseases. The swab for yeast is mixed with a drop of potassium hydroxide and is placed on a slide. If yeast are present, a specific branching pattern is seen through the microscope.
  
  
  
  • The doctor then may insert 2 fingers into the vagina and gently press on the uterus, ovaries, and surrounding areas to check for any tenderness or other problems. The doctor also may take blood and urine specimens after this exam. Women should not douche or have sexual intercourse 1-2 days before the exam because doing so may make the diagnosis more difficult.   


• In healthy children and adults, a quick exam in the mouth or of the skin usually confirms the diagnosis of candidiasis. If any confusion exists about the diagnosis, the doctor may obtain a small scraping of the area, which is placed on a slide with potassium hydroxide and examined for a branching pattern consistent with yeast. Sometimes a doctor removes skin flakes with a scalpel and puts the flakes onto a slide with a drop of potassium hydroxide and look for the pseudohyphae (branches without walls or compartments) that are the microscopic appearance of Candida.