Definition

Sputum smear (KOH test) is a test for the presence of fungal microorganisms in sputum.

Images:

Alternative Names

KOH test; Fungal smear

How the test is performed

Obtain a sputum sample by coughing deeply and expelling the material that comes from the lungs (sputum) into a specimen container. A smear of sputum is prepared with potassium hydroxide (KOH) and examined under the microscope. If it is positive, fungal cells can be observed.

How to prepare for the test

There is no special preparation.

How the test will feel

There is no discomfort.

Why the test is performed

The test may be performed when there is abnormal sputum production or when an infection of the lungs is suspected.

Normal Values

No presence of organisms is normal.

What abnormal results mean

Abnormal results indicate the presence of fungus such as histoplasmosis, coccidioidomycosis, or blastomycoses. White blood cells called eosinophils may also be present.

Additional conditions under which the test may be performed:

What the risks are

There are no risks.

Special considerations

Not applicable.

Lots More Information:
Coccidioidomycosis
Eosinophil count - absolute...
Simple pulmonary eosinophil...
Coccidioidomycosis - acute ...

Review Date:2/10/2006
Reviewed By: Kenneth Wener, M.D., Division of Infectious Diseases, Beth Israel Deaconess Medical Center, Boston, MA. Review provided by VeriMed Healthcare Network.