Dr. Roach: Most cases of H. pylori infection stem from unknown causes

Keith Roach
To Your Health

Dear Dr. Roach: Could you give some additional information about H. pylori infection? I was diagnosed with it recently, via biopsies taken during an endoscopic procedure. I was given instructions on antibiotics to be taken, which I followed through on. When talking to my doctor's physician assistant, I asked what could have caused the infection, to try to prevent it from recurring. I was given a very cursory response, including that it could have come from eating at "Mom and Pop" restaurants. From research I did after that, it seems that it can be present for a long period of time without being noticed, and many times the cause is unsure.

After I finished the antibiotics, I was told to have a follow-up test to make sure they were effective. I was given a choice of a stool test or a breathing test; I chose the breathing test. I was surprised at how easy it was. Are those tests also used to initially detect an infection, without a biopsy?

— A.J.Y.

Dear A.J.Y.: Helicobacter pylori is an important cause of chronic gastritis (stomach inflammation), the most important cause of stomach ulcers, and is an important factor in stomach cancer and intestinal lymphoma. Between 50% and 66% of the population of the world is affected. The older a person is, the more likely he or she is to have infection: in the U.S., it's about 10% in those between 18 and 30 years old, but 50% in those over 60. This likely represents an improvement in hygiene, as most infections are acquired in childhood and persist throughout life. It is thought that most infection occurs person-to-person, possibly through water or from poor handwashing before food preparation. H. pylori is much more common in developing nations. In the U.S., infection is more common in people of lower socioeconomic status.

Not everyone with H. pylori has symptoms or needs treatment. People with ulcers or gastritis are generally treated with several antibiotics for 10-14 days along with antacid medicine. The diagnosis can be made by biopsy, as yours was, or by the stool or breath test.

The breath test is at least 95% specific (if the test is positive, it's very likely to be a true positive) but 90% sensitive, meaning one person in 10 with the bacteria will have a false negative test. The stool test is close to 95% sensitive and specific. Blood testing is more likely to have false positive and false negative results. In addition to making the diagnosis, the stool or breath test is recommended to confirm eradication of the infection.

For more reading, I'd recommend you start at https://medlineplus.gov/helicobacterpyloriinfections.html.

Dear Dr. Roach: I'm getting low grade tumors in my bladder. I just had my second operation after the Bacillus Calmette-Guerin treatment didn't work. I read that tumors can't grow in an alkaline environment. Should I eat vegetables, like broccoli and sprouts? Also, would vitamin E and selenium be helpful?

— R.G.

Dear R.G.: It is true that having an acid urine pH is a risk factor for bladder cancer. Many fruits and vegetables make urine pH more alkaline, whereas meat and dairy make the urine more acid. Smoking also makes the urine more acid.

Eating more fruits and vegetables (and abstaining from smoking) will help reduce recurrence of bladder cancer, though I'm not sure it's through urine acidity. Please don't stop your doctor's recommendations, though, as diet alone is not adequate therapy for bladder cancer.

A 2012 study found no benefit in selenium and vitamin E on prevention of bladder cancer. It's unlikely to be significantly effective in treatment.

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