Stomach

Question 1

What is Helicobacter pylori?

Answer 1

Gram-negative, urease-producing spiral-shaped bacterium found in the gastric antrum. and areas of gastric metaplasia in the duodenum.

Question 2

How is H. pylori transmitted?

Answer 2

Fecal-oral route, typically acquired in childhood.

Question 3

What diseases are associated with H. pylori?

Answer 3

Chronic gastritis, peptic ulcer disease, gastric cancer, gastric B-cell lymphoma.

Question 4

What are the pathogenic mechanisms of H. pylori?

Answer 4

Increased acid secretion, disruption of mucous protection, reduced bicarbonate production, virulence factors.

Question 5

What are non-invasive tests for H. pylori?

Answer 5

Serology (antibody detection), urea breath test, stool antigen test.

Question 6

What are invasive tests for H. pylori?

Answer 6

Antral biopsy with histology, rapid urease test (CLO test).

Question 7

When should H. pylori be eradicated?

Answer 7

In peptic ulcer disease, atrophic gastritis, gastric lymphoma, post-gastric cancer resection, dyspepsia, family history of gastric cancer.

Question 8

What is the first-line H. pylori treatment?

Answer 8

Triple therapy: PPI (omeprazole) + clarithromycin + amoxicillin/metronidazole for 14 days.

Question 9

What is quadruple therapy for H. pylori?

Answer 9

Bismuth-based therapy: PPI + bismuth + metronidazole + tetracycline.

Question 10

What is peptic ulcer disease?

Answer 10

Loss of mucosa exposing the submucosa, typically in the stomach or duodenum.

Question 11

What are the main causes of peptic ulcers?

Answer 11

H. pylori, NSAIDs, smoking, steroids, Zollinger-Ellison syndrome, Crohn’s disease.

Question 12

How does duodenal ulcer pain differ from gastric ulcer pain?

Answer 12

Duodenal ulcer: worse when fasting/night. Gastric ulcer: worsens with food.

Question 13

What are complications of peptic ulcers?

Answer 13

Perforation, upper GI bleeding, gastric outlet obstruction.

Question 14

What artery is commonly involved in ulcer-related bleeding?

Answer 14

Gastroduodenal artery.

Question 15

What are risk factors for gastric cancer?

Answer 15

H. pylori, smoking, salted foods, pernicious anemia, previous gastric surgery.

Question 16

What are the types of gastric cancer?

Answer 16

Intestinal type (localized, ulcerated) and diffuse type (linitis plastica, signet ring cells).

Question 17

What is the initial diagnostic test for gastric cancer?

Answer 17

Gastroscopy with biopsy.

Question 18

What staging investigations are done for gastric cancer?

Answer 18

CT, endoscopic ultrasound, laparoscopy.

Question 19

What is the treatment for early-stage gastric cancer?

Answer 19

Surgical resection with curative intent.

Question 20

What is the treatment for advanced gastric cancer?

Answer 20

Chemotherapy, radiation, and palliative care if unresectable.

Question 21

What is the most common mesenchymal tumor of the GI tract?

Answer 21

Gastrointestinal stromal tumor (GIST).

Question 22

What genetic mutations are associated with GIST?

Answer 22

c-KIT (CD117) and PDGFRA mutations.

Question 23

What is the treatment for GIST?

Answer 23

Surgical resection + tyrosine kinase inhibitor (Imatinib) in advanced cases.

Question 24

Investigations •

Answer 24

Non-invasive testing for H. pylori infection • Endoscopy usually not indicated unless there are complications, but if done
multiple biopsies from the center and edge of the ulcer are taken to distinguish
benign from malignant ulcer (esp. if gastric ulcers) • Barium meal if gastric outlet obstruction is suspected.

Question 25

Management •

Answer 25

If ulcer associated with H. pylori à eradication therapy (confirmed by either a urea breath test or fecal antigen testing) • H. pylori-negative peptic ulcers are usually associated with aspirin or NSAIDs and are treated is with PPIs and stopping the offending medication. • Follow-up endoscopy plus biopsy is performed for all GUs to demonstrate healing and exclude malignancy (initial biopsies may be false negatives)