Fecalysis Flashcards
contains bacteria, cellulose, undigested foodstuffs, GI secretions, bile pigments, cells from the intestinal walls, electrolytes, and water
Normal fecal specimen
approximately excreted in a 24-hour period
100-200 g of feces
primary source of final breakdown.
Small intestine
Digestive enzymes secreted into the small intestine by the pancreas include
trypsin, chymotrypsin, amino peptidase, and lipase.
Only about ___ mL of ingested fluid is excreted in the feces
150 mL of ingested fluid
An increase in daily stool weight above 200g.
Diarrhea
Increase liquidity of stools.
Diarrhea
Frequency of more than three times per day.
Diarrhea
Types of Diarrhea
Acute and Chronic
Lasts less than 4 weeks
Acute Diarrhea
More than 4 weeks
Chronic Diarrhea
Caused by increased secretion of water.
SECRETORY DIARRHEA
Caused by poor absorption that exerts osmotic pressure across the intestinal mucosa.
OSMOTIC DIARRHEA
Caused by Bacterial, viral, and
protozoan infections, drugs, stimulant laxatives, hormones, inflammatory bowel disease
SECRETORY DIARRHEA
Cause by:
- Disaccharidase deficiency (lactose intolerance)
- Malabsorption (celiac sprue)
- Poorly absorbed sugars (lactose,sorbitol, mannitol)
- Laxatives, magnesium-
containing antacids, amebiasis, and antibiotic administration.
Osmotic Diarrhea
is useful in diagnosing pancreatic insufficiency and small-bowel disorders that cause malabsorption.
Fecal fat
Used to distinguished steatorrhea in maldigestion & malabsorption.
D-XYLOSE TEST
Indicates a malabsorption condition
Low D-xylose
Indicates pancreatitis
Normal D-xylose
Excessive movement of intestinal contents through the GI tract.
INTESTINAL HYPERMOTILITY
Caused by Enteritis, the use of parasympathetic drugs, or with
complications of malabsorption.
INTESTINAL HYPERMOTILITY
Used for collecting random specimens
Plastic or glass containers with screw-tops similar to those used for urine specimens
For quantitative testing such as fecal fats.
Timed specimen
most representative sample.
3 day collection
due to intestinal oxidation of
stercobilinogen to urobilin.
Brown color stool
Separate hard lumps (severe constipation)
Type 1
Lumpy and sausage-like (mild constipation)
Type 2
A sausage shape with cracks in the surface (normal)
Type 3
Like a smooth soft sausage or snake (Normal)
Type 4
Soft blobs with clear-cut edges (Lacking fiber)
Type 5
Mushy consistency with ragged edges (Mild Diarrhea)
Type 6
Liquid consistency with no solid pieces (Severe diarrhea)
Type 7
Upper GI Bleeding Iron Therapy Charcoal
Bismuth (antacids)
Black
Lower GI Bleeding Beets and food coloring Rifampin
Red
Bile-duct obstruction Barium Sulfate
Pale Yellow, White, Gray
Biliverdin/Oral Antibiotics Pancreatic disorders
Green
Bile-duct obstruction Pancreatic disorders
Bulky/Frothy
Intestinal constriction
Ribbon-like
Colitis Dysentery Malignancy Constipation
Mucus of blood streaked mucus
Specimens can be examined as wet preparations stained with methylene blue or as dried smears stained with Wright’s or Gram stain.
Leukocytes
seen in the feces in conditions that affect the intestinal mucosa.
Neutrophils
Available for detecting fecal leukocytes and remains sensitive in refrigerated and frozen specimens.
LACTOFERRIN LATEX AGGLUTINATION TEST
indicates invasive bacterial
pathogen
Lactoferrin
Entire slide is examined for exactly 5 minutes.
Muscle fibers
Number of red-stained fibers with well-preserved
striations is counted.
Muscle fibers
have visible striations running both
vertically and horizontall
Undigested fibers
exhibit striations in only one
direction.
Partially digested fibers
No visible striations
Digested fibers
presence of more than 10 is reported as
Increased
Patients should be instructed to include red meat in their diet
Before collecting the specimen
Specimens should be
examined within 24 hours of collection.
Neutral fats (triglycerides), fatty acid salts (soaps), fatty acids, and cholesterol
Fecal fats
Dyes used for staining in fecal fats
Sudan III, Sudan IV ,Oil red O
most routinely used for staining.
Sudan III
2 Parts of Staining Procedure
Neutral fat & Split fat
More than 60 droplets/hpf can indicate steatorrhea
Neutral fats
Both the number and size of the fat droplets must be considered
Split fat
100 droplets measuring 1to 8 um
Slightly increased
100 droplets measuring 6 to 75 um
increased, commonly seen in steatorrhea.
Principle: Pseudoperoxidase activity of hemoglobin from hydrogen peroxide to oxidize guiac reagent
gFOBT
Int: Blue color indicates gastrointestinal bleeding
gFOBT
Principle: Uses polyclonal anti-human antibodies specific for the globin portion of human hemoglobin.
iFOBT
Int: Positive test and control lines indicate GI bleeding.
iFOBT
Principle: Addition of sodium hydroxide to hemoglobin- containing emulsion determines presence of maternal or fetal blood.
APT Test
Int: Pink color indicates presence of fetal blood
APT test
Principle: Emulsified specimen placed on x-ray paper determines ability to digest gelatin.
Trypsin
Int: Inability to digest gelatin indicates lack of trypsin.
Trypsin
Principle: Immunoassay using an ELISA test
Elastase I
Int: Sensitive indicator of
Exocrine pancreatic insufficiency.
Elastase I
Principle: Addition of Clinitest tablet to emulsified stool detects presence of reducing substances
Clinitest
Int: Reaction of 0.5 g/dL reducing substances suggests carbohydrate intolerance.
Clinitest
