What is Helicobacter pylori gastritis?
Gastritis may result from infection with the bacterial organism Helicobacter pylori. It invades the mucosal lining of the stomach and is the cause of up to 95% of duodenal and up to 75% gastric ulcers and has also been associated with gastric and duodenal cancer and lymphoma.
How is it diagnosed?
During gastroscopy the appearance of the mucosa lining your stomach can be inspected for any evidence of gastritis, that typically results in red patches (erythema) and occasionally ulceration. Biopsies can be taken, which are painless, and allow a rapid acid ureas tests such as the Clotest® or Pronto Dry® test to be performed. This uses a colour indicator and usually turns pink if positive and gives a result within 60 minutes. Biopsies can also be sent for histopathology analysis to determine if there is active gastritis, and if it is associated with Helicobacter pylori organisms. This test typically takes a week to get a result.
Figure 1. The Clotest and Pronto Dry are both Acid Ureas tests that give a result within 60 minutes.
Why does Helicobacter pylori need to be eradicated?
Helicobacter pylori is a Class 1 carcinogen, meaning the chronic infection can lead to the formation of ulcers, and ultimately (over time) the formation of gastroduodenal cancer. The risk of gastroduodenal cancer is 6 times higher in those infected with Helicobacter pylori compared with those not infected . If it is treated, this bacterium can be eradicated completely and the risk of ulcers and cancer removed.
How is Helicobacter pylori eradicated?
If Helicobacter pylori is identified, it can be treated in patients without penicillin allergy by a two-week course of Nexium HP7® (amoxicillin 1g, clarithromycin 500mg & esomeprazole 20mg) taken twice daily. Alternatively, KlacidHP7® can be used (amoxicillin 1g, clarithromycin 500mg and pantoprazole 20mg) taken twice daily as a two-week course.
Figure 2. Nexium Hp7 therapy to eradicate Helicobacter pylori Gastritis.
What about patients Allergic to Penicillin?
Patients with penicillin allergy can replace the amoxicillin with flagyl 400mg twice daily.
How is eradication of Helicobacter pylori confirmed?
Confirmation of Helicobacter pylori eradication is done at 6 weeks with an acid ureas breath test which is the most accurate with a sensitivity and specificity of greater than 98%. It is important that you not take any acid-lowering medication for at least 6 weeks prior to your testing, as this can give a false negative result.
Figure 3. Acid ureas breath test performed at 6 weeks to confirm successful eradication.
Alternatively, a simple blood test can be performed at 3-6 months to measure the IgG for Helicobacter pylori. This is less accurate with reduced specificity, often giving a false positive results. If this blood test is positive it is recommended that an acid breath test be done to confirm actual positivity.
What do I do if my Acid Ureas breath test and blood test remain positive despite treatment?
If testing confirms continued infection with Helicobacter pylori, then a repeat 2-week eradication course of second line treatment is required. Clarithromycin resistance occurs in 20% of the population, therefore most advocate replacing clarithromycin 500mg twice daily with Ciprofloxacin 500mg twice daily as second line treatment for persistent positive cases. For third line therapy, ciprofloxacin 5oomg twice daily can be replaced with Levofloxacin 500mg twice daily.
Hartgrink HH, Jansen EP, van Grieken NC, et al; Gastric cancer. Lancet. 2009 Aug 8;374(9688):477-90. Epub 2009 Jul 20.