Helicobacter pylori is a Gram-negative, flagellated, urease-positive bacterium diagnosed via urea breath test or stool antigen. It colonizes the stomach antrum, using urease to survive acidic conditions. It causes gastritis, peptic ulcers, and increases the risk of gastric adenocarcinoma and MALT lymphoma. Treatment is triple or quadruple therapy including antibiotics and a PPI.
Helicobacter pylori es una bacteria Gram-negativa con forma de coma, flagelada, catalasapositiva, oxidasa-positiva y ureasa-positiva. Se diagnostica mediante prueba de aliento de urea o pruebas de antígeno fecal/anticuerpo. Coloniza el antro estomacal y utiliza la ureasa para neutralizar el ácido estomacal. Causa gastritis, úlceras pépticas (especialmente duodenales) y aumenta el riesgo de adenocarcinoma gástrico y linfoma MALT. El tratamiento implica terapia triple (amoxicilina/metronidazol, claritromicina, PPI) o terapia cuádruple basada en bismuto.
| Front | H.pylori Describe (3) main features How do you diagnose? Where does it mainly colonize and what is it pathogenesis? What does it cause? What is the treatment? |
|---|---|
| Back | Flagellated (motile) Triple Catalase (+) Oxidase (+) Urease (+) Diagnosis ↓ Urea breath test H.pylori Ab | Fecal Ag Pathogenesis → Colonizes mainly antrum of stomach → urease hydrolyzes urea to release NH3+ and CO2 → ammonia causes ↑pH and alkaline environment which helps organism survive in acidic mucosa as the urine also becomes alkaline Manifestations ↓ Weight loss (pain due to eating) Gastritis Peptic ulcers (especially duodenal) ↑ risk of the following conditions ↓ Peptic ulcer disease Gastric Adenocarcinoma MALT Lymphoma Treatment ↓ Triple therapy ↓ Amoxicillin (Metronidazole if penicillin allergy) Clarithromycin PPI (Omeprazole) ↓ "Antibiotics Cure Pylori" Bismuth-based quadruple therapy in macrolide resistance |
Tags: microbiology
Learn with these flashcards. Click next, previous, or up to navigate to more flashcards for this subject.
Next card: Leptospira interrogans weil's disease what
Previous card: Bscesses diabetics vid sugar eaters and lcoholics spirate
Up to card list: Microbiology 101 → Step 1 USMLE