helicobacter

what is the bacteria’s name we focused on?

Helicobacter pylori

where does Helicobacter usually reside in an infection?

stomach

• Helicobacter are microaerophiles

• stomach is the only microaerophilic environment in the body

what enzyme allows Helicobacter to survive in the stomach?

urease

how does urease help Helicobacter survive?

increases local pH by making ammonia → neutralizes the acid

how is Helicobacter transmitted?

most likely fecal to oral

whar are the symptoms of an infection?

ammonia is toxic to the cells lining of the stomach

ulcers may form

• regions of the stomach stop producing mucus

• stomach acids gets to those regions

how often are there symptoms at all?

70% of those infected never develop ulcers

what disease is H. pylori linked to?

gastric cancer

describe the urea breath test

feed urea with 13C isotopes (radioactive urea)

how does the urea breath test work?

if you have H. pylori in your stomach:

radioactive urea gets converted into radioactive CO2

look for exhaled 13CO2 (you burp)

how is an infection best treated?

antibiotics

pepto-bismol

• helps the ulcers heal

• mild antibiotic as well

how is H. pylori infections prevented?

hygiene/sanitation

what does a lack of H. pylori have a correlation to? why?

increased risk of childhood asthma

cleanliness hypothesis: some conditions (e.g. allergies, asthma) may actually be more likely if you live too clean a life