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.