Another disadvantage of the guaiac test
occurs with high dose ascorbic acid (vitamin C), resulting in a false negative.
Stool guaiac test
Annually beginning at age 50 Tests for blood in the
The results of the patient's stool guaiac test
were positive, and the complete blood count and metabolic panel were normal except for mild anemia.
If the guaiac test
(Fecatwin-S) was positive, the immunological test (FECA-EIA) was performed.
Its superior sensitivity and specificity reduces the rate of false positive results often associated with traditional guaiac test
A basic work-up should include complete blood count with differential, iron studies (ferritin, serum Fe, and total iron binding capacity), reticulocyte count, and a guaiac test
Subjects were excluded for the following reasons: positive guaiac test
within 6 months; iron-deficiency anemia within 6 months; rectal bleeding or hematochezia within 12 months; unintentional weight loss of more than 10 pounds within 12 months; optical colonoscopy in previous 10 years; barium enema in previous 5 years; history of adenomatous polyps, colorectal cancer, or inflammatory bowel disease; history of familial adenomatous polyposis or hereditary nonpolyposis cancer syndromes; rejection for optical colonoscopy for any reason; medical condition that precluded the use of sodium phosphate preparation; pregnancy.