Describe the relationship between gut flora and IBS, including how it relates to use of probiotics.
Dysbiosis (high ratio Firmicutes :Bacteroidetes, few Lactobacilli &Bifidobacteria-> activation gut immune system-->inflammation; attempt to restore symbiosis
Describe how the effects of NSAIDs, alcohol, cigarette smoke, and stress lead to the development of gastritis.
Decrease mucosal lining in stomach--> cells exposed to acid--> cell damage--> inflammation
What are the most common causative agents of traveler's diarrhea?
Enterotoxigenic Escherichia coli (ETEC), Campylobacter jejuni, Shigella spp., Salmonella spp., other E. coli strains
Differentiate between acute pancreatitis, chronic pancreatitis, and exocrine pancreatic insufficiency (EPI).
Pancreatitis: auto-digestion; Acute: enzymes prematurely activated/ Chronic: persistent inflammation; EPI: not making pancreatic enzymes (treat w/ pancrelipase)
Compare normal movement of ions and nutrients across intestinal epithelium to that of secretory diarrhea.
Water is absorbed on osmotic gradient; water follows solute. Secretory diarrhea: solute (such as Cl-) secreted into lumen--> water follows--> diarrhea
Describe the role of the lower esophageal sphincter and list factors that affect its functioning.
control entry of bolus--> stomach & prevent gastric contents from entering esophagus; RF: truncal obesity, nicotine,
Explain the pathophysiological effects of Enterotoxigenic Escherichia coli (ETEC) AB toxins in the stomach and intestinal tract.
increases cAMP--> upregulate CFTR and NKCCI cotransporter crypt cells--> secrete Cl- into lumen--> H2O and Na follow--> watery diarrhea
What are the signs, symptoms, and risk factors for acute pancreatitis?
N/V, tachycardia, fever, abdominal pain worse after eating, upper abdominal pain (radiates to back), ecchymosis; RF: alcohol, smoking, obesity, FHx
List recommended lifestyle approaches for people with IBS.
Compare/contrast normal pancreatic enzyme function to pancreatitis.
trypsin --> activates zymogens prematurely (in pancreas instead of in stomach)--> autodigestion of the pancreas-> high amylase + lipase=pancreatitis
What are potential long-term risks of prolonged gastric acid suppression?
increased risk of acid-labile bacterial infection; pepsinogen can't convert to pepsin--> poor digestion
What is the MOA, indications, and an example of a proton-pump inhibitor?
irreversibly block H+/K+ ATPase enzyme--> prevents movement of H+ ions; Indication: ++gastric acid; Omeprazole
Describe the MOA of loperamide and bismuth compounds.
Loperamide: binds peripheral mu in enteric NS--> slow colonic transit (no BBB); Bismuth: salicylate inhibits intestinal prostaglandin and Cl- secretion
Describe the major motor patterns that occur in the small intestines and colon during FED and FASTED conditions.