Urinalysis and Body Fluids 6th Edition by Majorie DiLorenzo, Susan Strasinger

Exercise 43

The term “occult” blood describes blood that:

A. Is produced in the lower GI tract

B. Is produced in the upper GI tract

C. Is not visibly apparent in the stool specimen

D. Produces a black, tarry stool

Step 1 of 2

Fecal occult blood:

Fecal occult blood is the hidden blood in the feces.

• When bleeding occurs in any portion of intestinal tract, the hemoglobin degradation changes the stool color black and tarry

• When bleeding occurs in “lower part” of gastrointestinal (GI), the blood appears in the red color and if bleeding occurs in “upper part” of GI then it leads to stool with black tarry

• When the bleeding occurs more than 2.5 mL/150 g the blood is not observable

• At this condition, performing fecal occult blood testing detects the fecal occult blood.

Therefore, fecal occult blood is not visible in the fecal specimen. Hence, the correct answer is option.