The anal sacs are glands located near the dog’s anus that produce secretions that are normally expressed during defecation. The secretions are normally pungent and straw-colored with brown flecks.
Overview of Anal Gland Problems in Dogs
Types of anal sac disease include:
- Infection or abscess formation
Anal sac impaction can lead to inflammation or infection of the anal sacs. Dogs are more commonly affected with anal sac disease than cats. Small breed dogs are more commonly affected with anal sac impaction than large breed dogs. Older female dogs are more commonly affected with anal sac tumors.
What to Watch For
- Scooting or dragging the anus on the ground or carpet
- Frequent licking of the anus or tail base
- Reluctance to sit or sitting asymmetrically to avoid pressure on the painful anal sac
- Straining to defecate, difficulty defecating, production of ribbon-like stools
Chronic/recurrent anal sac infections and anal gland tumors are indications for anal gland removal.
Diagnosis of Anal Gland Disease in Dogs
- A complete history
- A complete physical exam
- Rectal examination including an attempt to manually express the anal sacs
- Blood tests, as anal sac tumors can cause an increase in blood calcium levels
- Chest and abdominal X-rays to check for tumor spread to other organs
- Abdominal ultrasound to check lymph nodes for tumor spread
Treatment for Anal Gland Disease in Dogs
- Anal gland removal is done under general anesthesia
- One or both anal glands are removed as needed
- There is a small risk of fecal incontinence with any surgery around the anus, including anal gland removal. This risk is higher when both anal glands are removed than if only one is removed
- Tumors of the anal sacs can spread to lymph nodes in the abdomen. Affected lymph nodes can be removed, although this can be difficult
Be aware of your pet’s normal defecation habits and stool appearance so that you can notice any changes. Contact your veterinarian if you notice any of the above signs of anal sac disease. Follow your veterinarian’s instructions for home care after anal gland removal. Give medications as instructed and use an Elizabethan collar on your pet to keep licking at the surgery site.
In-depth Information on Canine Anal Gland Problems
The anal sacs are located at the 4 o’clock and 8 o’clock positions of the anus, and are embedded in the muscle of the anal sphincter. They are glands that produce a pungent yellowish secretion during defecation.
Anal Sac Impaction
Impaction is more commonly seen in small breed dogs and is the result of large amounts of thick anal sac secretions that cannot be expressed by the dog during defecation. The secretions build up and cause discomfort as the sac becomes distended.
The only symptoms you may notice are scooting or rubbing the anus on the carpet or ground, and excessive licking of the anus or tail base.
This is inflammation of the canine anal sac, which can be caused by impacted anal sac secretions or bacterial infections of the anal sacs. Anal sacculitis is more painful than anal sac impaction. In addition to scooting and excessive licking, you may notice your pet straining to defecate, being reluctant to sit, or sitting asymmetrically.
Anal Sac Abscess
This is a pus-filled anal sac that results from a bacterial infection. Anal sac abscesses are more painful than anal sac impaction. In addition to scooting, excessive licking, and straining to defecate, you may also notice a red swelling near the anus, or pus dripping from an open wound near the anus if the abscess has already ruptured.
Anal Sac Tumor
Anal sac tumors (apocrine gland adenocarcinomas) are not often painful and do not usually have redness on the overlying skin or any open wounds. They occur mostly in older female dogs, spayed as well as unspayed. They can cause an increase in blood calcium levels, which can cause clinical signs such as increased drinking and urination. They most often spread to the sublumbar lymph nodes, which are located in the abdomen right below the lumbar vertebrae. If the lymph nodes become enlarged due to spread of the cancer, they can obstruct flow of feces by putting pressure on the colon. This may show itself as difficulty defecating or producing ribbon-like stools. Dogs with anal sac tumors can also have symptoms associated with other types of anal sac disease, including scooting, excessive licking, straining to defecate, reluctance to sit, or sitting asymmetrically.
Anal gland removal is indicated in cases of chronic, recurrent anal sac infections and anal gland tumors.
Diagnosis In-depth of Anal Gland Problems in Dogs
- History. Your veterinarian will ask specific questions regarding defecation habits (straining, size/shape of stool, frequency, pain), appetite, weight loss, drinking and urination habits, what symptoms you have noticed and how long they have been going on.
- Physical exam. Your veterinarian will perform a complete physical exam, including a rectal exam of the anal sacs. The veterinarian will attempt to express the anal sacs and note the quality of the secretions.
- Blood tests. If your veterinarian suspects an infection or abscess of the anal sacs, he or she may recommend a complete blood count, which will assess the number and type of red and white blood cells and platelets. The white blood cell count will usually increase in an infection. If your veterinarian suspects an anal sac tumor, he or she will recommend a serum chemistry panel, important if the dog will need anesthesia. This test checks the major organs to see if they are functioning normally and also checks the levels of the major electrolytes in the body. Anal sac tumors can cause an increase in serum calcium levels.
- Chest and abdominal X-rays. Anal sac tumors can spread to lymph nodes and lungs, and rarely to other organs or bones of the body. X-rays are used to check for obvious spread of the cancer, although microscopic spread cannot be ruled out. Chest x-rays are also important in older dogs that will be undergoing anesthesia, to make sure that there is no heart or lung disease that would make anesthesia risky.
- Abdominal ultrasound. The most common location for anal sac tumors to spread is the sublumbar lymph nodes. These lymph nodes can become extremely large, and may be able to be palpated rectally. If not, they can be seen using an ultrasound. If the lymph nodes become very large, they can push on the colon and obstruct flow of feces. This can make defecation difficult and may alter the shape or size of the stool.
Anal Gland Removal in Dogs
- Anal sacculectomy. This is the technical term for surgical removal of the anal sac. It is often recommended for recurrent cases of anal sac infection or anal sac impaction, and is necessary for treatment of anal sac tumors. This can be done to one or both sides as needed. The animal is placed under general anesthesia and an incision is made over the anal gland. The gland is dissected away from the anal sphincter muscle and removed. It is submitted for biopsy.
- The possible risks of surgery, besides the risks of general anesthesia, are fecal incontinence, chronic draining tracts from residual infection or secretory tissue, recurrence of the tumor, and straining to defecate from postoperative anal scar formation.
- Sublumbar lymph node removal. If a tumor of the anal sac has spread to the sublumbar lymph nodes, then removal of the lymph nodes can be considered. This is a technically challenging procedure that can result in significant bleeding during surgery and could also result in temporary or permanent urinary incontinence since the nerves controlling urination are close to the lymph nodes. It is not curative, although it may alleviate some of the problems associated with the enlarged lymph nodes, such as difficulty defecating.
Home Care and Recovery of Dogs After Anal Gland Removal Surgery
Optimal treatment for your pet requires a combination of home and professional veterinary care. Follow-up can be critical, especially if your pet does not rapidly improve.
- Administer all prescribed medications as directed. Alert your veterinarian if you are experiencing problems treating your pet.
- Closely follow your veterinarian’s instructions for post-operative care, including exercise restriction for one to two weeks. This allows the incision to heal.
- Use an Elizabethan collar on your pet to prevent licking at the surgery site.