Fecal Analysis


Stool evaluation and examination.

To assess for indication of disease in the gastrointestinal (GI) tract evidenced in stool samples (e.g., presence of blood, white blood cells [WBCs], ova and parasites, rotavirus antigen, or Clostridioides difficile toxin) toward diagnosing GI bleeding, cancer, inflammation, and infection.

Patient Preparation
There are no fluid or activity restrictions unless by medical direction. Instruct the patient to follow a normal diet unless instructed otherwise. If the test is being performed to identify blood, instruct the patient to follow a special diet that includes small amounts of chicken, turkey, and tuna (no red meats); raw and cooked vegetables and fruits; and bran cereal for several days before the test. Foods to avoid with the special diet include beets, turnips, cauliflower, broccoli, bananas, parsnips, and cantaloupe, because these foods can interfere with the occult blood test. Instruct the patient not to use laxatives, enemas, or suppositories for 3 days before the test. As appropriate, provide the required stool collection container and specimen collection instructions.

Normal Findings
Method: Macroscopic examination, for appearance and color; microscopic examination for presence of parasites, larvae, or eggs, for cell count, and presence of meat fibers; leukocyte esterase for leukocytes; Benedict solution (copper sulfate) for reducing substances; guaiac for occult blood; x-ray paper for trypsin; enzyme immunoassay (EIA) for rotavirus antigen; immunoassay or molecular methods for Clostridioides glutamate dehydrogenase (GDH), toxin A or toxin B. Note: Multiplex molecular stool tests are available in some laboratories that can simultaneously test for a variety of pathogens (bacterial, viral, and parasitic).

CharacteristicNormal Result
AppearanceSolid and formed
Epithelial cellsFew to moderate
Fecal fatSee “Fecal Fat” study
Leukocytes (WBCs)Negative
Meat fibersNegative
Occult bloodNegative
Reducing substancesNegative
Trypsin2+ to 4+
Ova and parasites (O&P)No presence of parasites, ova, or larvae
Clostridioides difficile GDH, toxin A or toxin BNot Detected

Critical Findings and Potential Interventions

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