FIT Stool Quantitative Test

The fecal immunochemical test, or FIT, measures the concentration of human hemoglobin in stool using antibodies specific to human blood. Unlike older stool blood tests, this method does not require dietary restrictions and can detect very small amounts of bleeding. Elevated levels suggest bleeding somewhere in the gastrointestinal tract, which may result from inflammation, infection, ulcers, polyps, hemorrhoids, or colorectal cancer. Even mildly elevated results are clinically meaningful and typically warrant follow-up testing to identify the source. This marker does not diagnose a condition on its own but serves as an important signal that further evaluation is needed.