The liver makes bile to help digest food and break down fats. The gallbladder is a sac-like organ connected to the liver. The gallbladder stores bile and releases it into the intestines through a bile duct. Sometimes, when things go awry, gallstones form inside the gallbladder. Gallstones are also called choleliths or cholelithiasis. For some pets they can be no trouble at all for the rest of their lives. For others, gallstones can be potentially fatal if the gallbladder bursts open.
Gallstones are often made up of parts of the bile, such as cholesterol, bilirubin, and calcium. Under the right conditions, these substances layer together inside the bile, essentially forming a hard blob that eventually results in a solid stone.
These stones form because either the gallbladder isn’t functioning properly or something is wrong with the bile. A common cause is when a tumor or especially thick bile blocks the bile’s movement into the intestines. Abnormal bile can also occur when the pet has high cholesterol, bilirubin, or triglycerides. Poor diets, such as those with too much fat or not enough taurine and protein, can also cause gallstones.
In some cases, gallstones don’t cause the pet any problems, and no symptoms will be noticed; however, gallstones can sometimes lead to cholangitis, a painful, inflammatory condition in the gallbladder. Gastrointestinal symptoms, such as vomiting, diarrhea or loose stool, poor appetite, and sometimes a yellow tinge to the skin and eyes (jaundice) may be seen.
Should gallstones block the bile duct, bile may overfill the gallbladder, causing it to eventually burst open (rupture) like a water balloon, which is an absolute emergency. The pain from a rupture is significant: it’s the kind of pain that would send you to the ER in the middle of the night in a blizzard. Pets in this kind of pain may bite, so be careful during transport to the emergency hospital. Dogs and cats may also become weak or faint quite suddenly.
Gallbladder rupture is a life-threatening emergency
A ruptured gallbladder is a worst-case scenario; just be aware that it is a possibility.
To diagnose stones before they ever get to the point of rupturing the gallbladder, a veterinarian will perform a thorough physical examination. The tummy will be checked for signs of pain around the gallbladder. Bloodwork will likely be run to check for liver changes; increased bilirubin, calcium, or cholesterol in the blood; and to look for evidence of inflammation, dehydration, or infection. Next, x-rays will be taken to see if any stones are visible. Unfortunately, only about 50% of gallstones can be seen on x-rays. An ultrasound of the belly may also be needed. This allows the veterinarian to check the size of the gallbladder; look for signs of bile inside the belly; confirm gallstones; make sure the liver looks healthy; and see if the bile duct is blocked. These tests can also help the veterinarian determine what caused the stones, so that steps can be taken to prevent more from forming.
In all cases, treatment will depend on what signs your pet is experiencing. If the pet is not showing any symptoms, there likely isn’t any treatment needed other than watching and waiting. The veterinarian will probably want to monitor the pet periodically with bloodwork, x-rays, and/or ultrasound to ensure the stones don’t change or cause discomfort.
If your pet is showing symptoms of duct obstruction or pain, surgery to either remove the gallstones or the entire gallbladder may be necessary. If the gallbladder bursts, emergency surgery to remove it and uncontained bile from inside the belly is needed immediately. (Remember, a ruptured gallbladder is a life-threatening emergency.) Hospitalization and intensive care are often required after gallbladder surgery.
Sometimes medications that protect the liver, such as ursodiol or SAMe, will be prescribed to help keep the liver healthy. Antibiotics may also be given if an infection is suspected or if the gallbladder ruptured. Treating the cause of the stones with diet change or dietary supplementation may also be recommended.
For pets that don’t show symptoms, the long-term risk for issues is low. Bile duct obstruction may occur, but it’s not set in stone (no pun intended). Your veterinarian may recommend a special diet or discuss the importance of cutting out any table scraps or people food. A well-balanced diet is important for pets with gallstones.
For pets that need surgery, the chance for improvement is good, but gallbladder surgery can be risky. If bile leaks into the belly, pets can become extremely ill and may die. For pets that need emergency surgery because their gallbladder ruptured, chances of improvement are much lower than those whose gallbladder didn’t burst. Pets that survive the surgery may need to be hospitalized for a long time before they can safely be sent home to continue to improve.
If you suspect your pet has gallstones, call your veterinarian for a checkup. Fortunately, gallstones are not common, but the symptoms could be caused by something else that needs to be taken care of. If your pet was recently diagnosed with gallstones, be sure to follow all your veterinarian’s instructions and give all medications as prescribed. Call your clinic with any questions or concerns, especially if your pet does not improve.
VIN News Service commentaries are opinion pieces presenting insights, personal experiences and/or perspectives on topical issues by members of the veterinary community. To submit a commentary for consideration, email firstname.lastname@example.org.