Cholelithiasis in Dogs
Cholelithiasis is a medical condition resulting from the formation of stones in the gallbladder. Gallstones are typically made up of calcium or other secreted substances. Gallstones occur in dogs, but, the bile in dogs is different from that in humans in that it has low cholesterol saturation. In fact, in dogs there is usually lower cholesterol and calcium stone composition than in humans. Miniature Schnauzers, Poodles, and Shetland Sheepdogs may be predisposed to gallstones. Stones in the bile ducts or the gallbladder may be visible on an X-ray, or they may not. Unless there are serious symptoms, surgery is not recommended for gallstones.
The condition or disease described in this medical article can affect both dogs and cats. If you would like to learn more about how this disease affects cats, please visit this page in the PetMD health library.
Symptoms and Types
There are cases where there are no apparent symptoms. However, if there is an infection in addition to the gallstones, the dog may display vomiting, abdominal pain, fever, and jaundice.
Causes
There are several causes for gallstones that will be considered. A failure of the gall bladder to function can interrupt the bile flow, or the bile may be sludging; the bile may be supersaturated with pigment, calcium, or cholesterol; stone formation may be caused by inflammation, an infection, a tumor, or the shedding of cells; or, the stones may bring on inflammation and allow the invasion of bacteria.
Low protein can lead to the formation of stones in the gallbladder.
Diagnosis
In working toward a conclusion for the cause of cholelithiasis, your veterinarian will need to confirm or rule out diseases of the liver, pancreatitis, inflammation of the bile duct or gallbladder, and a gallbladder distended by an inappropriate accumulation of mucus.
A complete blood count will be ordered to look for bacterial infection, obstruction in the bile duct, or other underlying factors that could be causing the symptoms. X-rays are not usually very effective in looking at the gallbladder, but your veterinarian will probably want to use ultrasound to make an internal visual examination. Ultrasound imaging can detect stones, a thickened gallbladder wall, or an over sized bile tract. This can also be used as a guide for the collection of specimens for culture. Should surgery be recommended, a thorough examination of the liver before surgery will be necessary.
Treatment
There is disagreement over whether an attempt to medically dissolve the stones is appropriate if the dog does not seem to be in danger. If intravenous (IV) treatment is indicated, your dog will need to be hospitalized until it is stable. In some cases, exploratory surgery will be the treatment route chosen. If this is a chronic problem for your dog, new stones may form even if there is surgery to remove the existing ones.
Medications that can be used to treat the stones, and any related complications, will be pills to help dissolve the stones; vitamin K1 will be given intravenously if the patient is jaundiced; vitamin E will be prescribed if high liver enzymes or inflammation in the liver and bile duct are diagnosed; S-Adenosylmethionine (SAMe) may be prescribed to improve liver function and bile production; Antibiotics may also be warranted to treat associated infections, bacterial complications, or to prevent infection when outside intervention needs to be used (e.g., IV, surgery, or any treatment that necessitates going into the body).
Living and Management
A fat-restricted, high protein diet is most likely to be prescribed for the long term.
If your dog had surgery, a physical examination and testing will be needed every two to four weeks for as long as your veterinarian recommends it. Periodic ultrasound exams to evaluate the ongoing functioning of the liver and bile system will be called for. You will need to watch for any sudden onset of fever, abdominal pain, or weakness, since it may indicate infection from a breakdown in the bile functioning process.