Gastric Ulcer and Helicobacter Pylori Case Study

Study Notes

A 48-year-old man presents with a 2-month history of upper abdominal pain, associated with nausea.
Symptoms are exacerbated by coffee, soda, or alcohol consumption.
Antacids provide temporary relief.
Patient has a history of smoking for 20 years, occasional alcohol use, and frequent NSAID use.
Physical examination and vital signs are normal.
Abdominal examination reveals epigastric tenderness.
CBC shows mild hypochromic, microcytic anemia.
Upper GI endoscopy reveals diffuse gastritis and a gastric ulcer.

Helicobacter pylori is a spiral, Gram-negative bacterium, measuring 3 x 0.5-0.9 µm.
Possesses a single polar tuft of flagella for motility.
Requires microaerophilic conditions for growth: 10% CO2, 5% O2, 85% N2.
Does not grow anaerobically.
Grows optimally at 37°C.
Requires high humidity and 5-10% CO2 for growth.
Isolates can be grown on specialized media, including Butzler's medium, Skirrow's medium (similar to chocolate agar), and other media containing antibiotics like cefazolin, bacitracin, nalidixic acid, and amphotericin.
Colonies are typically small, translucent, gray, 1-2 mm in diameter, and weakly β-hemolytic.
Most H. pylori strains take 3-7 days to grow in culture.

Considered the primary risk factor for peptic ulceration, gastric adenocarcinoma, and gastric MALT (mucosa-associated lymphoid tissue) lymphoma.
Colonizes the stomach of approximately 50% of the global population.
Infection is present in 70%-90% of individuals with duodenal ulcers and approximately 70% of those with gastric ulcers.
Antibiotic treatment of H. pylori infection promotes healing of ulcers and reduces their recurrence.

H. pylori has several virulence factors that facilitate colonization of the stomach:
- Acid-inhibitory protein: Blocks acid production.
- Urease: Neutralizes stomach acid by producing ammonia.