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Occult Blood (GUAIAC) Test, Feces (8000100187)
Test Mnemonic:


Specimen Requirements:

Collect a fecal specimen; apply a thin layer to each of the sections of the Coloscreen card.


Coloscreen or Hemoccult cards, feces in clean, leakproof container


Refrigerate fresh stool, cards can be held at room temperature

Specimen Preparation:

Coloscreen/Hemoccult cards with flaps that are used to place a small amount of fecal matter on.


12 days

Causes for Rejection:

Samples in preservative, specimens other than feces, unlabeled or mislabeled specimens, incomplete collection information on requisition

Reference Range:


Turnaround Time:

Test is performed daily, Monday through Friday


 Detection of guaiac by color development


Clinical Microbiology

Clinical Indication:

 Screens and detects blood in gastrointestinal tract

Patient Preparation :

The patient should be placed on a high residue diet starting 2 days before the test. Foods to be avoided include red or rare meat, turnips, broccoli, horseradish, cauliflower, cantaloupe, and parsnip. Other factors which affect the test are medications (avoid aspirin, tonics or Vitamin C preparations), bleeding hemorrhoids, menses, other gastrointestinal tract disorders, such as colitis, gastritis, diverticulitis, and bleeding ulcers.

CPT 4 Code:



See diet and medication restrictions. It is recommended to collect three samples on three days for this test. If samples are received at the same time, the laboratory reports one result and  charges for only one test.

Occult blood collection supplies (Coloscreen cards)  available through Materials Management

When ordering tests for which Medicare or Medicaid reimbursement will be sought, physicians should only order tests that are medically necessary for the diagnosis or treatment of the patient. Components of the organ or disease panels may be ordered individually. The diagnostic information must substantiate all tests ordered and must be in the form of an ICD-10 code or its verbal equivalent.
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