Gastrointestinal Disorders 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)
- dissolving food (solvent)
- activating pepsin
- stimulates duodenal release of other digestive enzymes
- 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)
- transport undigested food for fecal removal (contains Haustra)
- 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)
- 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
- increase bicarb release (neutralize stomach acid)
- 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
- __ neutralizes gastric acid in duodenum and activates enzymes. Secretion is stimulated by secretin.
- ___ precursors to enzymes that break down proteins.
- ___ breaks down fats into fatty acids
- ___ increases blood glucose levels
- ___ decreased blood glucose levels
- amylase
- bicarbonate
- proteases
- lipases
- glucagon (produced by alpha cells)
- insulin (produced by beta cells)
Octreotide (somatostatin analog) is used in medical management of:
- GH producing tumors (acromegaly, gigantism)
- some pituitary tumors
- flushing and diarrhea associated w/ carcinoid tumors and VIP tumors
- 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)
- infectious in immunocompromised (Candida, CMV, HSV)
- meds
DX: Upper endoscopy
What type of esophagitis do the following endoscopic findings suggest and how do you treat them?
- Small, deep ulcers
- Large superficial shallow ulcers
- Linear yellow-white plaques
- multiple corrugated rings
- HSV- acyclovir
- CMV- Ganciclovir
- Candida- PO fluconazole
- 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
- OTC H2 blocker or antacids PRN
- H2 blocker, PPI (mod-severe)
- 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
- Odynophagia
- Weight loss
- 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:
- endoscopic ligation**
- Octreotide: vasoconstricts portal venous blood flow
- Vasopressin
- Baloon tamponade
- Trans jugular intrahepatic portosystemic shunt (TIPS)*
Prevention:
- nonselective BB: Propranolol, nadolol
- 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