ROUTINE FECALYSIS

Stool analysis: is a series of tests done on a stool sample to help diagnose certain conditions affecting the digestive tract, including infection ( such as parasites, viruses, or bacteria ) , poor nutrient absorption or cancer.

SPECIMEN COLLECTION Patient education

o Individuals have limited control in the timing of fecal excretiono Collection is highly undesirable for the patiento Verbal and written instructions should be provided along with the appropriate specimen container

Specimen containero Clean, non breakable, sealable and leak proof

Type and amount collectedo Routine fecalysis: peanut sizeo Quantitative test(3 day fecal collection): container used is paint cans

Contaminants to avoido Urine: affects detection of protozoao Tissue papero Toilet water: contains cleaning agents that affects the chem test)

1. Macroscopic examination Color:

o Brown -normal color (bilirubin)o Green - diet, antibiotics (biliverdin)o Black - GI (upper), charcoal, drugso Red - GI (lower), drugs

Consistency:o Formed- normalo Hard - constipation (scybala)o Soft - increased fecal contento Watery - diarrhea, steatorrhea

Mucus:o Normally not presento If present may indicate: straining during bowel movements , other GIT diseases

2. Microscopic examination Blood streaks and undigested food - if observed, report as PRESENT Parasites - if none, report as none seen Fecal fat

o Fecal stains: Sudan III, Sudan IV, Oil Red O ( neutral fat - triglycerides) Fecal leukocytes and rbc

o Normally not presento (+) - invasive/inflammatory, involvement of intestinal wall

PROCEDURE:o Emulsify stool in NSS approx diameter of 25 centavo pc.o A good preparation: a density such that newsprint could be read if place under the slide

o Make another wet mount using Lugol's iodine. (Examine for parasites). Do not air dry.

■NORMAL FECES Brown, soft, well formed NO blood, pus, bacteria, viruses, fungi, parasites Tubular shape or cylindrical ( reflecting passage through colon) Ph 6 <2 mg/g of sugars called reducing factors are present in stools Increased volume of stool - poor absorption of fats

■ABNORMAL FECES Blood, pus, mucus, bacteria, virus, parasites PRESENT High levels of fat - chronic pancreatitis, sprue (celiac disease), cystuc fibrosis, others Undigested meat fibers - pancreatitis > 6.8 ph - poor absorption of carbohydrates or fat, and problems with amount of bile in digestive tract < 5.3 ph -poor absorption of sugars Low level of enzyme ( trypsin or elastase) - -digestive complication of pancreas, problem conditions

(cystic fibrosis) Blood - bleein g indigestive tract Wbc - bacterial diarrhea. High level of reducing factor - problem digesting certai sugar (esp sucrase and lipase) Low level reducing factor - sprue, CF, malnutrition

o Medications ( colchine - for gout) or oral contraceptive may cause low levels

CHEMICAL TEST: FOBT (FECAL OCCULT BLOOD TEST)Principle: pseudoperoxidase activity of hemoglobin

Indicators:o Benzidine - most sensitive but carcinogenic so no longer usedo Orthotolidine- 2nd in sensitivityo Guaiac - least sensitive, INDICATOR OF CHOICE, eliminates false positive caused of dietary factors

Factors affecting testingo Improper collectiono Contamination ( menstrual or hemorrhoidal blood)o Defective guaiac or peroxide developero Storage of fecal specimen or slides beyond 6 days

False (+) - salicylates and iron supplements False (-) - antacids and ascorbic acid

Procedureo (+) - blue coloro Accurate or reliable - (+) blue line, (-) no color changeo Invalid - - (+)no color, (-) blueo Add 2 drops peroxide developer after placing 2 thick smears of stool from diff parts of the stool.