GI goljan small bowel disorders Flashcards
Signs and Sx of small bowel disease
colicky pain;
diarrhea;
anemia
Signs and Sx of large bowel disease
diarrhea; dysentery; pain; Tenesmus; Fe deficiency; Hematochezia
Define colicky pain associated w/ small bowel disease
pain then pain free interval accompanied by constipation & inability to pass gas;
Sx of bowel obstruction from adhesions from previous surgery
What is diarrhea a sign of in the small intestine?
infection;
malabsorption;
osmotic diarrhea
If bloody diarrhea occurs, what is this a sign of in the small intestine
infarction;
volvulus;
dysentery
Anemia from small intestine may be due to malabsorption of what?
iron
folate
vit B12
Diarrhea is a sign of what in the large bowel?
infection;
laxative abuse;
inflammatory bowel disease
If diarrhea is bloody, what is it a sign of in the large bowel?
infarction;
dysentery
Define dysentery and what is associated
bloody diarrhea w/ mucus => infection
What are the 5 causes of pain in large bowel disease?
inflammatory bowel disease; ischemic colitis; diverticulitis; appendicitis; peritonitis
define tenesmus as a sign in large bowel pain
painful, ineffective straining at stool => commonly in ulcerative colitis
If a patient is iron deficient, what should be considered?
polyps;
colorectal cancer
Define hematochezia and its causes
massive loss of whole blood per rectum
causes: sigmoid diverticulosis (most common); angiodysplasia
define diarrhea
more than 250g of stool/day;
acute diarrhea=> less than 3wks
chronic diarrhea=> over 4wks
What are the 3 types of diarrhea?
invasive (inflammatory);
secretory;
osmotic
What are important screening tests for diarrhea?
fecal smear for leukocytes;
stool osmotic gap
How do you calculate stool osmotic gap?
300mOsm/kg - 2x(random stool Na+ + random stool K+)
what is the stool osmotic gap for secretory diarrhea? what does it indicate?
Gap < 50mOsm/kg from POsm => indicates diarrheal fluid approximates POsm
What is the stool osmotic gap for osmotic diarrhea?
Gap > 100mOsm/kg from POsm => indicates hypotonic loss of stool due to presence of osmotically active substances
What is the pathogenesis of lactase deficiency?
colon anaerobes degrade undigested lactose into lactic acid and H2 gas leading to abdominal distention w/ explosive diarrhea
What diseases are associated w/ malabsorption?
Pancreatic insufficiency; Bile salt/acid deficiency; small bowel disease; Celiac disease; Whipple disease
Define malabsorption
increased fecal excretion of fat w/ concurrent deficiencies of fat-soluble vitamins, minerals, carbs, proteins
What is the pathogenesis of malabsorption?
pancreatic insufficiency;
bile salt/acid deficiency;
small bowel disease
What is pancreatic insufficiency most common cause?
chronic pancreatitis due to alcohol in adults and CF in children
In pancreatic insufficiency, what leads to maldigestion of fats? how does it present?
diminished lipase activity => presents w/ neutral fats and fat droplets in the stool
in pancreatic insufficiency, what leads to maldigestion of proteins? how will it present
due to diminished trypsin => presents w/ undigested meat fibers in stool
in pancreatic insufficiency, what alters carb digestion?
carb digestion is NOT affected => amylase is present in salivary glands and disaccharidases present in brush border of intestinal epithelium
what are bile salt/acid needed for?
required to micellarize monoglycerides and fatty acids
What are the 5 pathogenesis for bile salt/acid deficiency?
inadequate synthesis of bile salts/acids from cholesterol;
intrahepatic/extrahepatic blockage of bile;
bacterial overgrowth in small bowel w/ destruction of bile salts/acids;
excess binding of bile salts;
terminal ileal disease
What are examples of intrahepatic/extrahepatic blockage of bile that may lead to bile salt/acid deficiency?
primary biliary cirrhosis;
stone in common bile duct
What are examples of bacterial overgrowth in small bowel that may cause destruction of bile salts/acids?
small bowel diverticula;
autonomic neuropathy
examples of bile salt/acid deficiency due to excess binding of bile salts?
cholestyramine
How does terminal ileal disease lead to bile salt/acid deficiency? give examples
prevents recycling of bile salts/acids =>
ex: Crohn’s disease; resection of ileum
How does small bowel disease lead to malabsorption?
loss of villi will lead to decreased reabsorption of micelles into enterocytes
What is pathogenesis of small bowel disease leading to malabsorption?
inability to reabsorb micelles due to loss of villous surface;
lymphatic obstruction
What are examples of diseases associated w/ inability to resorb micelles?
celiac disease;
Whipple’s disease