Stool AnalysisWhat is the stool or feces?

5. Epithelial cells that have been shade

1. Waste residue of indigestible material (cellulose during the previous 4 days) 2. Bile pigments and salts

3. Intestinal secretions, including mucus 4. Leukocytes that migrate from the bloodstream

6. Bacteria and Inorganic material(10-20%) chiefly calcium and phosphates. Undigested and unabsorbed food.

Random Collection1. Universal precaution

2. Collect stool in a dry,clean container

3. uncontaminated with urine or other body secretions, such as menstrual blood

4. Collect the stool with a clean tongue blade or similar object.

5. Deliver immediately after collection

Ova and parasites collection

1. Warm stools are best for detecting ova or parasites.

Do not refrigerate specimen for ova or parasites.

2. If the stool should be collect in 10 % formalin or PVA

fixative, storage temperature is not critical.

3. Because of the cyclic life cycle of parasites, three

separate random stool specimens are recommended.

Enteric pathogen collection

1. Some coliform bacilli produce antibiotic substances that

destroy enteric pathogen.Refrigerate specimen immediately.

2. A diarrheal stool will usually give accurate results.

3. A freshly passed stool is the specimen of choice.

4. Stool specimen should be collected before antibiotic therapy, or

as early in the course of the disease.

5. If blood or mucous is present, it should be included in the

specimen

Interfering factors1. Patients receiving tetracyclines, anti-diarrheal

drugs, barium, bismuth, oil, iron , or magnesium may not yield accurate results.

2. Bismuth found in toilet tissue interferes with the results.

3. Do not collect stool from the toilet bowl.A clean, dry bedpan is the best.

4. Lifestyle, personal habbits, environments may interfere with proper sample procurement.

Normal values in stool AnalysisNormal values in stool Analysis

Macroscopic examination Normal Macroscopic examination Normal valuevalueAmount 100-200 g / day

Colour Brown

Odour Varies with pH of stool and depend on bact-erial fermentation

Consistency Plastic, not unusual to see fiber, vegetable skins.

Size and shape Formed

Gross blood,Mucous,Pus, Parasites None

Normal values in stool Normal values in stool analysisanalysis

Microscopic examination Microscopic examination Normal Normal valuesvalues

Fat (Colorless, neutral fat (18%)and fatty acid crystals and soaps)

Undigested food None to small amount

Meat fibers, Starch, Trypsin None

Eggs and segments of parasites None

Yeasts None

Leukocytes None

Normal values in stool analysisNormal values in stool analysis

Chemical examinationChemical examination Normal Normal valuesvaluesWater Up to 75 %

pH 6.5-7.5

Occult blood Negative

Urobilinogen 50-300 g/24hr

Porphyrins Coporphyrins:400-1200g/24hr

Uroporphyrins:10-40 mg/24hr

Nitrogen <2.5 g/24hr

Normal values in stool Normal values in stool analysisanalysis

Chemical examinationChemical examination Normal Normal valuesvaluesBile Negative in adults:positive in children

Trypsin 20-950 units/g( positive in small amounts

in adults; present in greater amounts in normal children.

Osmolarity used 200-250 mOsm with serum osmol- arity to calculate osmotic gap

Sodium 5.8-9.8 mEq / 24hr

Normal values in stool Normal values in stool analysisanalysis

Chemical examinationChemical examination Normal Normal valuesvaluesChloride 2.5-3.9 mEq / 24 hr

Potassium 15.7-20.7 mEq /24 hr

Lipids ( fatty acid) 0-6 g / 24 hr

Clinical ImplicationsClinical Implications1.1. Fecal consistency may be altered in Fecal consistency may be altered in various disease statesvarious disease states

a. Diarrhea mixed with mucous and red blood cells is associated with

1. Typhus 2. Typhoid 3.Cholera

4. Amebiasis 5. Large bowel cancer

Clinical ImplicationsClinical Implications

b. Diarrhea mixed with mucus and white blood cells is associated with

1. Ulcerative colitis 2. Regional enteritis

3. Shigellosis 4. Salmonellosis

5. Intestinal tuberculosis

Clinical ImplicationsClinical Implications

C. ”Pasty” stool is associated with a high fat content in the stool:

1. A significant increase of fat is usually detected on gross examination

2. With common bile duct obstruction, the fat gives the stool a putty- like appearance.

3. In cystic fibrosis, the increase of neutral fat gives a greasy, “butter stool” appearance.

Stool OdorStool OdorNormal value Varies with pH of stool and diet.

Indole and sketole are the substances that produce normal odor formed by intestinal bacteria putrefaction and fermentation.

Clinical implication.

1. A foul odor is caused by degradation of undigested protein.

2. A foul odor is produced by excessive carbohydrate ingestion.

3. A sickly sweet odor is produced by volatile fatty acids and undigested lactose

Stool pHStool pH

Stool colorStool color

Blood in StoolBlood in Stool

Mucous in StoolMucous in Stool

Fat in StoolFat in Stool

Urobilinogen in Urobilinogen in StoolStool

Bile in StoolBile in Stool

Trypsin in Trypsin in StoolStool

Leukocytes in StoolLeukocytes in Stool

Porphyrins in Stool

Stool Electrolytes