KOH test; Fungal smear - sputum
A sputum fungal smear is a laboratory test that looks for fungus in a sputum sample.Sputum is the material that comes up from air passages when you cough very deeply.
A sputum sample is needed. You will be asked to cough deeply and spit any material that comes up from your lung into a special container.
The sample is sent to a lab. A small amount is lightly smeared onto a microscope slide and mixed with potassium hydroxide (KOH). The slide is examined under the microscope and checked for fungus parts.
There is no special preparation.
There is no discomfort.
Your doctor may order this test if you have abnormal sputum production or signs of a lung infection.