Trucker MD
Kidney stones and gallstones: What’s the difference?

By John McElligot, MD

You’re cruising down the road with a good-paying load of electronics, and suddenly you don’t feel so good. Sweaty, sick to your stomach – it doesn’t take long before you think you are going to pass out.

If you have a kidney stone that’s trying to pass, you are in for some serious pain. If you’ve ever had one, you know you never want to experience that again. Gallstones aren’t fun, either. So what’s the difference, anyway? Here are some questions from truckers who want to know.

A year ago I had a sudden attack on the road that turned out to be a kidney stone passing. It was excruciating, and I was forced to go to the ER. I was told that due to my sex (male) that I would likely have one again. Is this true? What can I do to keep from having one again?

Kidney stones can be quite painful and unpredictable as far as onset. It would be helpful if you knew the type of stone, since calcium stones tend to be found in people who produce more oxalate in their urine. Oxalate is a mineral found in too many foods to list here, but if your doctor wants you on a low-oxalate diet, you’ll need to research this a bit and lay off certain foods and cut back on salt.

There are certain calcium stones that are formed from the phosphate and calcium and have no specific dietary cause. Other stones – such as struvite, uric acid and cystine stones – are less common and do have dietary contributors such as decreased water intake, high-protein diets, and recurrent urinary tract infections.

As far as the predominant sex that have a preponderance for kidney stones? Yes, males do outnumber females on this particular statistic.

Overall, kidney stones have no definite single cause.

Do most kidney stones pass on their own or is surgery normally required?

Surgery is not normally needed for kidney stones. Most urinary tract stones pass on their own with the assistance of high fluid intake and occasional pain medications.

However, struvite stones can become quite large and can require lithotripsy, which uses shock waves to break up the stones and make them small enough to pass. If the stones are in a location that the shock waves can’t reach, your doctor may also recommend a more invasive surgical procedure. 

Are gallstones different from kidney stones? Can you have gallstones and not even know about it? Can they cause cancer?

Gallstones have little similarity to kidney stones. Unlike kidney stones that pass from your body through the urinary tract, gallstones pass through the intestines.

A large percentage of gallstones are formed from cholesterol. The remaining stones tend to be pigmented stones from bile salts.

Gallstones can be asymptomatic for many years. You may not even know you have one. However, when they became large or the gallbladder becomes inflamed, you may feel pain. However, autopsies have revealed that gallstones are often found in people who have never had any symptoms of gallbladder disease.

As far as your question regarding cancer and gallstones, I won’t go so far as to say they cause cancer. However, gallstones are found in 80 percent of the people with gallbladder cancer. I might add that there are many other complications of gallbladder disease. If your doctor determines that you have gallbladder stones or what we call acalculus cholecystitis (no stones, just inflammation), I recommend you have your gallbladder removed on an elective surgery basis.

Don’t wait until you are chronically symptomatic and/or have an infection that may precipitate emergency surgery. LL

John McElligott is an MD, Fellow of the American College of Physicians, and medical director of the St. Christopher Truckers Development and Relief Fund. This column is the opinion of the writer and does not necessarily reflect the opinions of Land Line Magazine or its publisher.