Peptic Ulcer & Gastroesophageal Reflux Disease Flashcards
Name the 2 main causes of peptic ulcer disease?
NSAID’s and H. Pylori Infection.
How do NSAIDs cause peptic ulcers?
They inhibit COX-1 in the Arachadonic Acid pathway, inhibiting prostaglandin synthesis.
Prostagladins (PGE2 and PGI2) activate mucous cells to secrete mucus and bicarbonate to protect the lining. They also inhibit HCl secretion by binding to the PG receptor on parietal cells.
Lack of prostaglandins could cause an imbalance of damaging and protecting factors of the epithelium.
How does H. Pylori infection cause peptic ulcers?
H. Pylori are gram-negative bacteria which live in the mucosa under epithelium.
It has urease activity which converts urea to ammonia. This raises the pH surrounding the bacteria and gives D and G cells a ‘false reading’ of the stomach’s pH.
This leads to HCl production by reducing somatostatin and increasing gastrin release.
How is peptic ulcer disease diagnosed?
Blood test for IgG antibodies.
Stool antigen test.
C13 breath test: Patients swallow urea labelled with C13. If isotops has split from urea due to urease activity it is present in CO2 in patients breath.
Endoscopy and biopsy: Used to view the GI tract and biopsy can be used for pH analysis via C14 test which changes colour.
How are peptic ulcers treated?
Antibiotics: To eradicate H. Pylori infection. E.g. Clarithromycin or Amoxicillin.
PPI’s: Inhibit the H+/K+ ATPase proton pump on parietal cells which pumps out H+ ions.E.g. Omeprazole - can inhibit 90% of receptors if taken around 30 mins after eating when most pumps are active.
H2 Receptor Antagonists: Supress acid secretion by blocking histamine receptors on parietal cells. E.g. Cimetidine.
Define Gastro-oesophageal Reflux Disease (GORD)?
Retrograde passage of acidic gastric contents into the oesophagus.
List the protective mechanisms of the oesophagus?
Superior and inferior sphincter
Intra-abdominal oesophagus through hiatus.
Angle of HIS
Secondary peristalsis
What is a hiatus hernia? What are the types?
Protrusion of part of the stomach through the diaphragmatic hiatus into the chest.
Sliding hernia: Stomach gastro-oesophageal junction slides through hiatus superiorly.
Rolling hernia: Fundus protrudes superiorly through hiatus with GO junction.
List red flag GI symptoms.
Unexplained weight loss Dysphagia Persistant vomiting GI blood loss Upper abdominal mass.
Describe the process of swallowing?
Food bolus pushed up to soft palate into pharynx.
UES relaxes, respiration pauses and glottis is closed.
Primary peristaltic wave propels bolus to stomach.
LES opens at initiation of swallowing.
Secondary peristalsis occurs locally in response to distension.
List intrinsic and extrinsic causes of dysphagia?
Intrinsic: Foreign body, stricture, benign/malignant.
Extrinsic: Lymph nodes, enlarged left atrium.
List functional causes of dysphagia?
Motility disorders: Achalasia, oesophageal spasm.
Neuromuscular disorders: Cerebrovascular disease, Bulbar palsy.
Describe 3 complications of GORD?
Oesophagitis: Inflammation of squamous mucosa secondary to acid damage. Can cause strictures.
Barrett’s Oesophagus: Columnar transformation of squamous mucosa caused by chronic acid damage.
Adenocarcinoma: Accumulating cellular genetic changes causing dysplasia and ultimately cancer.
Name tests for GORD?
High Resolution Manometry - Records pressures via catheter in nose to diagnose motility disorders.
Endoscopy - Used to see structural and mucosal abnormalities, can be used to take biopsy.
List treatments for GORD.
Lifestyle measurements: Weight loss, stop smoking/reduce alcohol, avoid precipitants.
Antacids.
Alginates.
H2 Receptor Antagonists.
Proton Pump Inhibitors.
Surgical management: Nissan Fundoplication (fundus wrapped round inferior oesophagus to re-enforce closing of the LES).
