semana 3 enf acido peptica + gastritis

Which of the following is the most common cause of gastric ulcers?

• Severe bruns

• Traumatic brain injury

• Infection with H pylori

• Persisten NSAID use

Answer explanation

While all the above answer choices can cause gastric ulcers, H. pylori infection is the most common cause of gastric ulcers. H. pylori produces CagA toxin to break the mucus barrier and urease to promote bacterial survival within the gastric antrum.

[Choice A]: Curling ulcers are caused by severe burn injuries that cause hypovolemia and subsequent mucosal ischemia.

[Choice B]: Cushing ulcers can result from a CNS injury that increases intracranial pressure, which then increases vagal stimulation. Acetylcholine from vagal tone then causes increased gastric acid production.

[Choice D]: NSAIDs inhibit both COX-1 and COX-2. This inhibition reduces prostaglandin production which leaves the gastric mucosa unprotected, making it more susceptible to acidic insults.

Key Takeaway:

• The most common cause of gastric ulcers is infection with H. pylori.

• Other subtypes of gastric ulcers include Curling ulcers, Cushing ulcers, and NSAID-induced ulcers

Where does H pylori reside in the stomach?

• Within the submucosa

• Within the mucosa

• Below the submucosa

• Above the mucosa

Answer explanation

H. pylori never dives past the gastric mucosa. It resides on top of the mucosa(blue star), using its CagA toxin to break down the mucus barrier. 

Which medications are included in triple therapy for h pylori infection?

• Metronidazole, bismuth, proton pump imhibitor

• Amoxicilin, clarithromycin, proton pump inhibitor

• Bismuth, tetracycline, proton pump inhibitor

• Clarithromycin, amoxicilin, bismuth

Answer explanation

Triple therapy for H. pylori infection includes amoxicillin, clarithromycin, and a proton pump inhibitor.

On the other hand, quadruple therapy includes bismuth, tetracycline, metronidazole, and a proton pump inhibitor.

Mnemonic: The triple therapy for H. pylori can be remembered with the phrase "Antibiotics Cure Pylori": Amoxicillin, Clarithromycin, PPI. 

The quadruple therapy can be remembered with the phrase "Please Make Tummy Better": PPI, Metronidazole, Tetracycline, Bismuth.

Which of the followins is not included in quadruple therapy for H pylori infection?

• Amoxicilin

• Bismuth

• Tetracycline

• Proton pump inhibitor

Answer explanation

Quadruple therapy for H. pylori infection includes bismuth, tetracycline, metronidazole, and a proton pump inhibitor.

Mnemonic: The triple therapy for H. pylori can be remembered with the phrase "Antibiotics Cure Pylori": Amoxicillin, Clarithromycin, PPI. 

The quadruple therapy can be remembered with the phrase "Please Make Tummy Better": PPI, Metronidazole, Tetracycline, Bismuth.

Where are gastric ulcers most commonly found?

• Within the fundus

• Lessr curvature of the antrum

• Within the body

• Greater curvature of the antrum

Answer explanation

Gastric ulcers are most commonly found in the lesser curvature of the stomach.

Which of the following statements regarding gastric ulcers is true?

• Benign ulcers are more likely to have irregular heaped up amrgins

• Epigastric pain improves with meals

• Persisten NSAID use increases the amount of unprotected gastric mucosa

• Malignant ulcers are typically smaller than 3cm, while benign ulcers are typically bigger than 3cm

Answer explanation

NSAIDs reduce prostaglandin E2 (PGE₂) production. Typically, PGE₂ plays an important role in maintaining gastric mucus to combat gastric acid. 

With reduced prostaglandin, there is reduced gastric mucus, putting the stomach at an increased risk of ulcer formation.

[Choices A and D]: Benign gastric ulcers classically have sharply demarcated margins and are < 3 cm in size, while malignant gastric ulcers classically have irregular heaped-up margins and are > 3 cm in size.

[Choice B]: Patients with gastric ulcers tend to have epigastric abdominal painthat worsens with meals.

Key Takeaway:

• NSAIDs decrease prostaglandin production, thereby increasing the risk of gastric ulcer formation.

WHich H pylori protein is associated with a diagnostic breath test?

• CagA toxin

• Proteasa

• Ureasa

Answer explanation

H. pylori produces the urease protein, which is able to break down urea into ammonia and carbon dioxide. The diagnostic urea breath test makes use of this feature; in this test, a patient consumes radiolabeled urea, and the amount of exhaled isotope-labeled carbon dioxide is subsequently measured. The presence of radiolabelled carbon dioxide means that the radiolabelled urea was broken down by urease; this implies the presence of H. pylori!

[Choice A]: The CagA toxin breaks down the mucus barrier of the stomach.

[Choice B]: The protease protein also helps break down the mucus barrier of the stomach.

Key Takeaway:

• H. pylori's urease enzyme underlies the foundation of the urea breath test.

• The test utilizes radiolabeled urea and measures the amount of isotope-labeled carbon dioxide exhaled after urea ingestion.

What is the underlying pathology in acute gastritis?

• Alkaline damage to the stomach mucosa

• Chronic irritation of the sotmach mucosa

• Overproduction of gastric mucus

• Acidic damage to the stomach mucosa

Answer explanation

Gastritis is defined as acidic damage to the stomach mucosa. Common causes include NSAID use, stress, and heavy alcohol use. 

[Choice B]: Chronic gastritis is defined as persistent irritation of the stomach mucosa. Common causes include autoimmune gastritis and H. pylori infection. 

[Choice C]: There is no overproduction of mucus In acute gastritis. Instead, there is an imbalance between gastric acid levels and mucus production. The excess gastric acid overpowers the mucus, resulting in mucosal damage.

Key Takeaway:

• Acute gastritis results from acidic damage to the stomach mucosa.

Significant hemorrhage from gastric ulcers typically results in bleeding from wich artery?

• Celiac trunk

• Left gastric artery

• Gastroduodenal artery

• Splenic artery

Answer explanation

Significant hemorrhage secondary to gastric ulcers classically occurs from the left gastric artery. 

Which of the following is true regarding duodenal ulcers?

• Anterior duodenal ulcers calssically cause severe hemorrhage

• Patients typically experience wieight loss

• The mos common cause of duodenal ulcers is a duodenal gastrinoma

• Associated epigastric pain tends to improve with meals

• Posterior duodenal ulcers always cause pneumoperitoneum

Answer explanation

Duodenal ulcers are commonly caused by H. pylori (90%) or Zollinger-Ellison syndrome (< 10%). Symptomatically, patients with duodenal ulcers experience epigastric abdominal pain that improves with meals.

[Choices A and E]: Anterior duodenal ulcers are more likely to perforate and cause pneumoperitoneum, whereas posterior duodenal ulcers are more likely to hemorrhage (typically from the gastroduodenal artery).

[Choice B]: Patients with duodenal ulcers typically experience weight gain as the epigastric pain is improved with meals. This is in sharp contrast to gastric ulcers in which patients typically experience weight loss as epigastric pain is worsened with meals.

[Choice C]: Duodenal gastrinoma is indicative of Zollinger-Ellison syndrome, the second most common cause of duodenal ulcers.

Key Takeaway:

• Duodenal ulcers are most commonly caused by H. pylori infection.

• For patients with duodenal ulcers, epigastric abdominal pain tends to improve with eating.

• Anterior duodenal ulcers tend to perforate, whereas posterior duodenal ulcers tend to hemorrhage.