Originally published in The Ottawa Citizen July 15, 2003
Original Title: The Stones Wrong Address Part 1: How green is my valley

Part 2
Part 3

The Canadian Museum of Nature has exquisite colourful and exotic-looking crystal, mineral and stone collections. The human body also harbours interesting mineral, stones and crystal deposits.

Stones commonly form in the gallbladder, kidney and salivary glands. Crystals form in several joints most, notably the knee and the big toe as seen with gout. Starting with the gallbladder, we will look at how each arises, where they collect and how to treat and prevent serious complications.

The gallbladder is a seven to 15-centimetre muscular sac-like organ located in the upper right side of the abdomen hanging off the underside of the liver.

A duct system connects the gallbladder to the liver, pancreas and small intestine. It functions as a reservoir for bile salts, cholesterol and other fatty substances produced in the liver. Bile aids in digesting of fatty foods. The gallbladder contracts after a fatty meal, pumping bile into the intestine.

Gallstones form under conditions that promote a hardening of these substances. Surgical removal of the gallbladder, or cholecystectomy, is the most common abdominal surgery in medicine.

Gallstones come in two types: cholesterol and pigment. Eighty to 90 per cent of all gallstones are cholesterol stones. Pigmented stones contain less than 20 percent cholesterol and account for the remaining ten to 20 per cent.

There are numerous risk factors for gallstone formation. People of Scandinavian, Native American Pima Indian, Hispanic, and western Caucasian backgrounds are at greater risk. So are those with a maternal family history of gallstones. Pregnant women and women in general are at greater risk, as are middle-aged and obese people.

Those who have fasted frequently and undergone rapid weight loss are also at risk. So are those who have taken the birth control pill, postmenopausal estrogens, progesterone and cholesterol-lowering fibrates (Gemfibrozil, Bezalip, Lipidil Micro, Lipidil Supra) among others. Cholesterol lowering statins do not cause gallstones

Other risk factors include high levels of triglyceride (a type of fatty molecule), diabetes, Crohn’s disease, cirrhosis (scarring) of the liver and bile duct and Sickle cell disease among other conditions associated with rapid destruction of red blood cells.

Sixty per cent of people with gallstones do not have symptoms and are often unaware they have them. Usually gallstones are found during an abdominal ultrasound done for other medical reasons.

If someone experiences a gallstone attack, the likelihood of another is about 70 per cent.

Symptoms occur when the stone either leaves the gallbladder and winds its way down the common bile duct into the intestine or becomes lodged in the neck of the gallbladder. Typically, the pain will begin suddenly, intensify over 15 minutes and last for about three hours.

Pain typically localizes just below the bottom tip of the breastbone and shift toward the upper right-hand side of the abdomen. Palpating this area produces more discomfort. The pain may radiate directly to the upper back or to the back of the right shoulder.

Other symptoms can include nausea, vomiting, and intolerance to fatty foods. This sudden attack is biliary colic although the term ‘colic’ is a misnomer since the pain is steady and does not wax and wane. Once the gallbladder relaxes several hours after eating, the stone will often fall back into it and the pain subsides.

The most common imaging test to diagnose and screen for gallstones is an abdominal ultrasound. There are other tests available for specific studies of gallbladder function. X-rays play a lesser diagnostic role since they can only detect mineral-rich pigmented stones.

Of the 40 per cent of people who develop symptoms of gallstones, 70 to 80 percent experience biliary colic and ten per cent will develop infections and inflammation of the gallbladder (acute cholecystitis).

The gallbladder is likely to become infected and/or inflamed if the stone partially or completely blocks the small duct that leads out of it. Fever can develop and pain lasts longer than three hours. Acute cholecystitis is a surgical emergency. In many elderly patients, there may be no fever and pain, only some local tenderness in the right upper quadrant.

The goal is to prevent the complications of duct blockage: perforation of the gallbladder, infection or inflammation of the gall bladder or bile duct, inflammation of the pancreas (pancreatitis) or liver damage.

Next week’s column will look at the treatment and prevention of gallstone complications.

---

© Dr. Barry Dworkin 2003