Vaginal Yeast and Pseudohyphae, Qualitative — KOH Preparation
A microscopic examination of vaginal fluid that looks for yeast and pseudohyphae, which may be associated with a vaginal yeast infection.
["This test looks for fungal forms in vaginal fluid that can support a diagnosis of vaginal candidiasis."]
Key facts at a glance
- LOINC
- 55312-3
- Short code
- Yeast pseudohyphae Vag Ql KOH Prep
- Synonyms
- Yeast pseudohyphae Vag Ql KOH Prep
- Category
- liver
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 10
- Ref high
- 40
- Critical range
- — – 500 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- koh-preparation
- CPT
- 84484
- SNOMED
- 302774002
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What is this test?
This test examines a sample of vaginal fluid for yeast and pseudohyphae. These fungal forms may be seen with vulvovaginal candidiasis, commonly called a vaginal yeast infection.
Why might I need this test?
A clinician may order it when there is vaginal itching, burning, redness, soreness, or an unusual discharge. It can help distinguish a yeast infection from other causes of vaginal symptoms.
How is the test performed?
A clinician collects vaginal fluid and prepares it with potassium hydroxide, or KOH. The sample is viewed under a microscope to check for yeast and pseudohyphae, and the result is reported as detected or not detected.
How do I prepare for the test?
Follow the clinician's collection instructions. Tell the clinician about any vaginal creams, suppositories, or douches used recently, because these products may affect the sample.
Reference range
Adult: 10-40 U/LN/A
No special preparation required. Avoid fatty meals before the test if possible.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Finding yeast or pseudohyphae may support vaginal candidiasis, particularly when symptoms are typical. Yeast can occasionally be present without causing symptoms, so results should be interpreted with the examination and clinical history. A negative result does not completely rule out infection if symptoms remain concerning.
Short name
Vaginal yeast and pseudohyphae (KOH prep)
Frequently asked questions
What does a positive result mean?
Does this test identify the exact Candida species?
Can I use vaginal medication before the test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy