Why does my chest ‘crack’ when I breathe in and out? Ask your GP DR MARTIN SCURR

During a recent health check, my family doctor suggested a chest x-ray after noticing “crackling sounds” when inhaling and exhaling. I am 62, a non-smoker, and very active. What could be the cause?

Kay Parton, Oxfordshire.

The term crackles is used to describe the abnormal breathing sounds heard when a doctor listens to the chest with a stethoscope.

It is a rattling sound, one of several chest sounds that can indicate a potential problem. Other sounds include rhonchi (wheezing); friction rub (an audible ‘rasping’ sound); and stridor (many of us will have heard this when caring for a child with croup).

Crackling sounds (also called rales) are heard when the lungs are affected by pneumonia (an infection in the air sacs in the lungs, which can fill with fluid), bronchitis (inflammation of the airways), or edema (fluid in the lung tissue, usually caused by heart failure).

It is difficult to explain why you hear a crackling sound in someone like you, who is active and healthy and does not cough.

In your longer letter you mention that you had Covid last summer and asked if that played a role, but that seems unlikely, since you are feeling well now.

Your GP has referred you for a chest x-ray. If this shows no abnormalities, I would be reassured, especially if the crackling sounds have now disappeared.

However, if the symptoms persist, I would recommend that you have a spirometry done. This is a lung function test that measures how much air you can exhale at one time. This can help determine if there is a problem with the lungs.

If the results of this test are normal, there is another possibility: silent acid reflux, in which small amounts of stomach acid leak into the esophagus but do not cause the usual heartburn symptoms.

When this happens, especially at night, acid can spray into the lungs and similar crackling sounds can come from the chest.

I strongly urge you to have yourself re-examined.

Although it is not a treatment, it may be helpful in improving the balance of beneficial bacteria in your gut

I have had chronic diarrhea since April 2023 after a bout of gastroenteritis. I have been referred to a gastroenterologist but expect a significant wait and am getting desperate.

Name and address will be provided.

In case of chronic diarrhea that lasts for more than a year, a diagnosis is necessary.

You write in your longer letter that your GP has performed tests which show that infectious organisms such as E. coli, salmonella and campylobacter have been ruled out.

Those tests showed that your fecal calprotectin levels, a marker in the blood that indicates inflammation in the colon, were elevated.

This can be the result of an infection, but also of prescribed medications, diverticular disease (where bulges develop in the intestinal wall), inflammatory bowel disease and, in rare cases, colon cancer.

My opinion is that your diarrhea is indicative of intestinal haste. Food rushes through your intestines and arrives only partially digested and susceptible to fermentation in the colon, causing gas and diarrhea.

The question is why? The gastroenterologist will almost certainly recommend a colonoscopy, which uses a camera to inspect the lining of the large intestine.

In the meantime, you can safely take a probiotic such as Symprove or VSL 3, available from the pharmacy, until you have seen a specialist.

It is not a treatment, but it can be helpful by improving the balance of good bacteria in your gut.

Also keep track of your weight, because losing weight can also be a big problem. Tell your doctor about this.

In my opinion: Doubts about DNA cancer testing

I first heard about the Galleri test a few years ago, a single blood test that could detect over 50 types of cancer. It seemed like a huge step forward.

But the follow-up research not only provided answers, but also raised questions.

The aim of the test, called a liquid biopsy, is to find fragments of cancer DNA in the blood, which could help diagnose 75 percent of all cancers early – and offer the best chance of a cure.

The big, and still unanswered, question is how accurate is this in detecting cancer that is not yet causing symptoms?

A 2021 study of 150,000 people published in the Annals of Oncology found that the test detected only 16 percent of stage 1 (very early) cancers.

The Pathfinder study published last year found that 1.4 percent of participants tested positive, while 62 percent of the time it turned out to be a false positive.

Another question is how the location of the cancer is discovered so that it can be removed if a blood test is positive.

Time and methodical research will tell whether my early enthusiasm was justified.