Anal Sac Disorders In Dogs

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Dogs have two anal sacs located internally at the anus at about 5 and 7 o’clock. These sacs should normally be expressed when a dog is having a bowel movement. Fluid inside the sacs help lubricate the stool as it passes through ducts that exit the anus and the material from the sacs aid in the passage of feces. Normal anal sacs will express a clear to brownish secretion. The secretion does have a very strong, bad odor that can be extremely offensive, and most dogs will immediately start to clean the anus area if the anal sacs have been released. Some dogs will express their anal sacs in cases of fear, anxiety, or during stressful events. Smaller breeds seem to be more predisposed to anal gland problems, but they can occur in any breed.

Three common types of anal sac disorders are impaction of the anal sacs, sacculitis or inflammation of the anal sacs, and abscess or infection of the anal sacs. The signs that owners will see when it comes to anal sac disorders are scooting (dogs will drag their rear end across carpet or outside on grass, etc.), licking or chewing at the anus area repeatedly, soreness and redness at and around the anus, swelling at the anus, discomfort noted during a normal bowel movement, or possibly even discharge near the anus if the anal gland ruptures due to an abscess.

Predisposing factors that can lead to anal sac disorders include ongoing soft stools or bouts of diarrhea. The anal glands need firm stool in order to be expressed. Dogs with current allergies, whether food or environmental tend to have anal sac disorders throughout their lives, especially as the anal tissue will change over time due to chronic itching. Another factor that can lead to problems is that certain dogs are born with or develop over time very narrow anal sac ducts that don’t allow complete expression of the glands. Other dogs will just produce excessive secretions from the anal sacs, and the glands will fill up at a faster pace.

Any of these predisposing factors can lead to the common disorders seen with anal glands. Inflammation of the anal sacs or sacculitis will occur if the sacs are filled up with normal material or thickened material due to retained secretions that are just not being expressed when the animal has a bowel movement. Impaction of the anal sacs occurs when the secretion in the anal sacs builds up over time, and the secretion is too thick to be expressed or the duct of the anal sacs are clogged up or not working properly. An anal sac abscess will occur over time if the anal sacs continue to get larger, and the retained secretions can lead to the development of infection. An anal sac abscess can also rupture internally or externally where owners will actually see an open draining area at the anus.

Anal sac disorders can be extremely uncomfortable for dogs. Any dog showing the clinical signs described above should be seen by a veterinarian in order to diagnose the condition properly. Physical examination, history, and palpation of the anal sacs are the only way to diagnose anal sac disorders. Upon examination the anal sacs could need to just be expressed, flushed out, and have an antibiotic placed in the sacs if badly infected, or establish drainage for an abscess. Dogs with anal sacculitis and anal sac abscesses will need systemic antibiotics and possibly pain medication.

There is surgery for dogs that have continual problems with their anal sacs. The surgery consists of complete removal of both anal sacs. The other reason for considering surgical removal of the anal sacs would be the concern of the development of a neoplastic (cancerous) process with the anal sac.