PANCE Prep- GI Flashcards
Describe the role of HCl and Pepsin and what stimulates their release
HCl (secreted by parietal cells in response to histamine, acetylcholine and gastrin) 1. dissolving food (solvent) 2. activating pepsin 3. stimulates duodenal release of other digestive enzymes 4. kills harmful bacteria in the food Pepsin: (secreted as inactive pepsinogen by chief cells and becomes activated by HCl acidic environment) 1. digests proteins into smaller peptides
____ stimulates stomach acid secretion and motility. This hormone is inhibited by ___
gastrin Somatostatin via negative feedback
What are the main functions of the large intestines
- absorb water from undigested food (main fxn) 2. transport undigested food for fecal removal (contains Haustra) 3. absorb vitamins produced by bacteria (Vit. K and biotin)
___ is associated w/ no suppression of gastrin levels with the secretin test
Zollinger-Ellison Syndrome (ZES) *gastrin producing tumor)
What are the main functions of the duodenum?
- most chemical digestion (via secretin and CCK) 2. regulates rate of gastric emptying
What are the functions of Secretin and CCK
Secretin: (released by duodenum), inhibits parietal cell gastric acid production and causes pancrease to release bicarb (to buff acid from chyme leaving the stomach entering the duodenum) CCK: aids in breakdown of fats and proteins by stimulating pancreatic release of digestive enzymes 2. increase bicarb release (neutralize stomach acid) 3. stimulates gallbladder contraction and bile release (bile salts help emulsify fats into smaller micelles
Biliary colic is usually worse when? this is due to ___
after a fatty meal -due to CCK mediated contraction of the gallbladder and release of bile
What organ has both endocrine and exocrine functions
pancreas
- ____ breaks down starches into simple sugars 2. __ neutralizes gastric acid in duodenum and activates enzymes. Secretion is stimulated by secretin. 3. ___ precursors to enzymes that break down proteins. 4. ___ breaks down fats into fatty acids 5. ___ increases blood glucose levels 6. ___ decreased blood glucose levels
- amylase 2. bicarbonate 3. proteases 4. lipases 5. glucagon (produced by alpha cells) 6. insulin (produced by beta cells)
Octreotide (somatostatin analog) is used in medical management of:
- GH producing tumors (acromegaly, gigantism) 2. some pituitary tumors 3. flushing and diarrhea associated w/ carcinoid tumors and VIP tumors 4. bleeding esophageal varices
Diagnostic test of choice for achalasia and nutcracker esophagus
Esophageal manometry (motility study)
MC causes of esophagitis and how do you diagnose
- GERD (MC) 2. infectious in immunocompromised (Candida, CMV, HSV) 3. meds DX: Upper endoscopy
What type of esophagitis do the following endoscopic findings suggest and how do you treat them? 1. Small, deep ulcers 2. Large superficial shallow ulcers 3. Linear yellow-white plaques 4. multiple corrugated rings
- HSV- acyclovir 2. CMV- Ganciclovir 3. Candida- PO fluconazole 4. Eosinophilic- remove foods that incite allergic response or inhaled topical corticosteroid w/o spacer
-Heartburn (pyrosis**) often retrosternal that is worse with supine position -Regurgitation, dysphagia -Chest pain
GERD (transient relaxation of LES) DX: clinical, endoscopy, esophgeal manometry, 24 hr pH monitoring (gold standard but only if sx are persistent) TX: 1. lifestyle modification 2. OTC H2 blocker or antacids PRN 3. H2 blocker, PPI (mod-severe) 4. Nissen fundoplication if refractory
What is Barrett’s Esophagus?
esophageal squamous epithelium replaced by precancerous metaplastic columnar cells *risk of developing adenocarcinoma
What are ALARM sx of GERD
- Dysphagia 2. Odynophagia 3. Weight loss 4. Bleeding
-Dysphagia w/ both solids and liquids vs -stabbing CP worse w/ hot or cold liquids/foods
achalasia -DX: esophageal manometry (GS)-increased LES pressure >40 -double contrast esophagram- “Birds beak” appearance of LES Diffuse esophageal spasm -DX: esophagram- “corkscrew”
dysphagia, sense of lump in the neck, neck mass, regurgitation of food, cough, halitosis (old, trapped food pouch)
Zenker’s Diverticulum (pharyngoesophageal pouch) *diverticulum only involves mucosal pouch
Full thickness rupture of the distal esophagus -associated w/ repeated forceful vomiting -retrosternal chest pain worse w/ deep breathing and swallowing -hematemesis -PE: creptius on chest auscultation due
Boerhaave Syndrome DX: Chest CT/CXR: pneumomediastinum Contrast esophagram (GS)
What is Mallory Weiss Syndrome/Tears?
superficial longitudinal mucosal erosions following persistent retching/vomiting typically after ETOH DX: upper endoscopy TX: supportive - acid suppression to help promote healing
Dysphagia + esophageal webs + iron def. anemia= ___
Plummer-Vinson Syndrome *often has atrophic glossitits DX: barium esophagram
esophageal varices are dilation of the gastroesophageal collateral submucosal veins mostly likely due to ___
portal HTN and cirrhosis
TX of acute active esophageal varices bleeds, and prevention of rebleeds
Acute tx: 1. endoscopic ligation** 2. Octreotide: vasoconstricts portal venous blood flow 3. Vasopressin 4. Baloon tamponade 5. Trans jugular intrahepatic portosystemic shunt (TIPS)* Prevention: 1. nonselective BB: Propranolol, nadolol 2. Isosorbide: long acting nitrate Abx Prophylaxis: fluoroquinolones or ceftriaxone
MC cause of esophageal CA worldwide:___ (MC in ___ esophagus) MC cause of esophageal CA in US: ___ (MC in ___ esophagus) MC cause of gastric CA worldwide: ___
squamous cell- in upper 1/3rd of esophagus adenocarcinoma- in lower 1/3rd of esophagus adenocarcinoma