L07. Chapter 16 - Fecal Analysis PDF

6/26/2024 Fecal Analysis Chapter 16 Preamble PowerPoints are a general overview and are provided to help students take notes over the video lecture ONLY. PowerPo int s D O NOT c ove r the de tails nee de d fo r the Unit e xam Each student is responsible for READING...

6/26/2024 Fecal Analysis Chapter 16 Preamble PowerPoints are a general overview and are provided to help students take notes over the video lecture ONLY. PowerPo int s D O NOT c ove r the de tails nee de d fo r the Unit e xam Each student is responsible for READING the TEXTBOOK for details to answer the UNIT OBJECTIVES Unit Objectives are your study guide (not this PowerPoint) Test questions cover the details of UNIT OBJECTIVES found only in your Textbook! 1  6/26/2024 Introduction Nasty but necessary Provide insight to disorders: Feces are the end-product of body Gastrointestinal (GI) bleeding metabolism Liver and biliary duct disorders Provides valuable information Maldigestion/malabsorption Analysis syndromes Pancreatic diseases Macroscopic Inflammation Microscopic Diarrhea and steatorrhea Chemical Detection and identification of pathogenic bacteria, viruses, and parasites Physiology Fecal specimen contains bacteria, cellulose, undigested foodstuffs, GI secretions, bile pigments, cells from the intestinal walls, electrolytes, and water 100 to 200 g of feces is excreted in a 24-hour period Many species of bacteria = normal flora in the intestine The small intestine is the primary site for the final breakdown and reabsorption of proteins, carbohydrates, and fats Aid ed by pa ncrea tic enzymes tha t include tr yp sin, chymotr ypsin, amino pep tidase and lipases Liver p roduces bile salts that break down fats 2  6/26/2024 Approximately 9000 mL of ingested fluid, saliva, gastric, liver, pancreatic, and intestinal secretions enter the digestive tract each day Majority of fluids involved in digestion are reabsorbed. Only 500 -1500 ml will make it to the large intestine, with only about 150 mL excreted in feces Excess water (>3000 mL) reaching large intestine = diarrhea Diarrhea Definition: >200 g stool weight per day with increased liquid and more than three movements per day Mechanisms of diarrhea: secretory, osmotic, altered motility Illness duration Water diarrhea has 2 types Mechanism’ 1. Secretory Severity 2. Osmotic types (fecal electrolytes) Stool characteristics Laboratory tests: fecal electrolytes, osmolarity, and pH Stool characteristics Normal fecal osmolarity = serum osmo >4-week duration = chronic Sodium, potassium, osmolarity used to calculate fecal osmotic gap 60 per hpf indicative of steatorrhea Split fat is more indicative 7  6/26/2024 Qualitative Fecal Fats NEUTRAL FAT SPLIT FAT 1. Homogenize one part stool 1. Mix specimen wit h ac et ic ac id a nd with two parts water. hea t 2. Mix emulsif ied stool with 2. Free fa tt y acids a nd fat t y acids from one drop 95% ethyl alcohol soa p hy droly sis an d n eu tral fats on slide. 3. Nu mber a nd siz e evaluat ed: normal up to 100 sma ll droplets( 60 per hpf indicative of corn ers steatorrhea Qualitative Fecal Fats Soaps and fatty acid do not stain on the split stain Neutral count the number of fat droplets Splits count the number and the size of the fat droplets Reported under high power f ield Normal =