Dear Doctor: Because of the potential risks of proton pump inhibitors, should I have an H. pylori breath or stool test to make sure I have this bacterium before committing to long-term treatment with a PPI?

Dear Reader: That's an excellent question, and it reflects our increasing knowledge about both the bacterium and PPIs. First identified in 1982, Helicobacter pylori is a bacterium that causes chronic inflammation of the stomach lining and stomach, as well as duodenal ulcers; it can also lead to gastric cancer and a slow-growing type of cancer known as MALT lymphoma. In fact, H. pylori is the most common chronic bacterial infection in humans. As for PPIs, they can cause deficiencies in some nutrients and increase the risk of infection with the bacterium C. difficile.

Because these PPIs (Nexium, Prilosec, Prevacid, Aciphex, Protonix, Dexilant) decrease the acidity in the stomach, allowing for healing of inflamed tissues, they're used to treat inflammation in the stomach; ulcers of the stomach or the duodenum; and acid reflux.

Whether you should take PPIs long-term depends on your condition. In most cases for which the medication is prescribed long-term, you would have an endoscopy to visualize the esophagus, stomach and the duodenum (first portion of the small intestine). If the endoscopy found a stomach or duodenal ulcer, your gastroenterologist would have tested for H. pylori with a rapid urease test or with a biopsy test. So if you had an endoscopy that found an ulcer, you likely already have your answer.

If you didn't have an endoscopy and have been diagnosed with gastritis, then I would recommend checking for H. pylori. If you're infected, you could be treated with antibiotics instead of a long-term PPI. The breath test for H. pylori evaluates the bacterial infection's ability to break down urea, a chemical compound excreted in urine, and produce carbon dioxide. This is a very good test with an 88 to 95 percent sensitivity in picking up the organism, but the sensitivity decreases substantially if you are already taking a PPI.

One study in those taking the PPI Prevacid found the sensitivity of the urea breath test decreased by 33 percent. The stool test for H. pylori has a sensitivity of 94 percent in picking up the organism. It is also more cost-effective than the breath test. But again, if you are already taking a PPI or even Pepto-Bismol, the sensitivity significantly decreases.

If you're considering taking a PPI long-term for acid reflux (heartburn), there has been no proof that treating an H. pylori infection would improve the acid reflux unless you had an ulcer in the duodenum. Again, this is something that would be seen on endoscopy. Regarding acid reflux, you should first look at stopping cigarette smoking, alcohol, caffeine and chocolate before considering long-term use of a PPI.

In summary, if your doctor diagnoses you with gastritis, an H. pylori stool test would be of benefit. If your doctor suspects an ulcer, then I would recommend getting an endoscopy, during which you would be tested for H. pylori.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: My brother, who is 65, was diagnosed with inclusion body myositis about five years ago, and the muscles in his arms, legs and hands are deteriorating rapidly. He's someone who loves life, so this is very hard to watch. His physician says there's no cure. What can you tell me about the disease? Is it being studied anywhere?

Dear Reader: We're very sorry to hear about your brother's struggles. We know from experience how difficult it is to see a loved one be unwell and be unable to help.

Inclusion body myositis, also known as IBM, is a progressive degenerative muscle disease, sometimes also referred to as a muscle wasting disease. The word "progressive" means that once the disease process begins, it will continue to advance.

As you already learned, there is no treatment or cure for IBM at this time. However, advances in the areas of precision medicine and immunotherapy will hopefully lead to new methods to manage, if not cure, the disease.

Let's start with what is known about inclusion body myositis.

There are two types of IBM. One, which is extremely rare, is inherited. It results from a genetic defect that is passed along from a parent's DNA. The other form, which has no genetic link and is slightly more common, is known as sporadic. Sporadic IBM, also referred to as s-IBM, is seen most often in people 50 years and older. It is more common in men than in women.

Although the exact cause of s-IBM is not yet known, it is believed to be the result of a malfunction in the immune system. In autoimmune disorders, the body's defense mechanisms mistakenly attack healthy tissue. In s-IBM, certain white blood cells attack muscle tissue and cause ongoing inflammation. There is also a second avenue of attack, which causes the muscle fibers to degenerate.

For many people, the first symptom of s-IBM is an increasing tendency to stumble, trip or fall. This is due to damage to the quadriceps, the large muscles of the thighs. The muscles of the wrists and fingers are also often affected.

Treatment at this time focuses on the use of corticosteroids to address inflammation, or drugs to suppress the immune system. However, several types of new drugs are now being studied in ongoing clinical trials. These are focused both on the inflammatory response in s-IBM, as well as stopping the progression of muscle destruction. Although some participants in the clinical trials have shown modest or even good response to the drugs, the benefits thus far have proven to be short-term.

If you are interested in learning more about clinical trials for s-IBM, visit clinicaltrials.gov, a government website that lists studies receiving federal funding, as well as some that are funded by private industry.

For information about clinical trials at the National Institutes of Health Clinical Center, located in Bethesda, Maryland, call the NIH Patient Recruitment Office at (800) 411-1222. Or you can email prpl@mail.cc.nih.gov.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: Does zinc help with colds?

Dear Reader: Zinc is an important element needed for a healthy immune system. The link between zinc deficiency and infections was first noted in the Middle East 50 years ago. Some zinc-deficient patients had such severe immune dysfunction that they died by age 25 from infection. That's because cells that are deficient in zinc have a decreased production of interleuken-2, a necessary immune and inflammatory regulator. In the United States, this level of deficiency is rare because zinc is found in so many foods; elsewhere, it's seen among the severely malnourished.

As for its benefits, a United Kingdom study of people 65 and older found no benefit in the severity or the number of days of infection with a common cold among those taking a multivitamin that contained 20 milligrams of zinc versus those who took a placebo.

When it comes to higher doses, the results are more mixed. A review of 13 studies assessed the impact of zinc on the common cold. Daily doses varied from 30 mg up to 207 mg. The majority of the studies had people use lozenges every two hours while awake. The effects of zinc lozenges were compared to the effects of a placebo, and participants took them as long as the cold symptoms lasted. Seven studies found benefit with the use of zinc lozenges, while six did not.

The authors concluded that the greatest factor in regards to zinc efficacy was the dosage. In the studies that used less than 75 mg per day, no benefit was seen. However, seven of the eight studies that used more than 75 mg did show benefit. Of these seven studies, zinc lozenges decreased the duration of a cold from 0.4 days up to 3.6 days.

A separate 2012 review of 17 studies, with a combined total of 2,121 participants, also analyzed the impact of zinc lozenges or tablets compared to placebos. Three of the studies focused on children under 18. Overall, of the 17 studies, only eight measured the duration of symptoms, finding that zinc decreased symptoms on average by 1.65 days. However, no benefit was seen in children, and doses of less than 75 mg per day were linked to a decreased duration of symptoms of only 0.84 days. The research also showed a mild benefit in reducing the severity of symptoms in adults, but not in children.

In both review studies above, participants reported significant nausea and a bad taste in the mouth with the use of zinc. Note that the FDA has warned against the use of nasal preparations with zinc due to an irreversible loss of smell.

In summary, studies suggest a mild benefit for adult colds with the use of high daily doses of zinc. But, at these doses, you may be trading the benefits of decreased cold symptoms with the side effects of nausea. If you can tolerate a daily dose of greater than 75 mg, then zinc may be a good addition when fighting a cold.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)