Selective IgA Deficiency in Dogs

Selective IgA Deficiency is the most common immune deficiency disorder not only in humans, but in dogs. The breed that is most IgA deficient is the German Shepherd. Antigens, including bacteria, viruses or toxins/poisons, try to attack a canine’s immune system. If healthy, the dog’s immune system will rally, and respond by creating immunoproteins, which then begin to function as antibodies and provide immune protection. Antibodies then serve to dispel the antigen from the body.

The immunoglobulin A (IgA) is essential to the health of any living thing; with dogs, it aims specifically to protect their skin, as well as their respiratory, digestive, and reproductive systems. Overall, a dog with this deficiency will present with a generalized weakness and a lack of a healthy appearance. A puppy with Selective IgA Deficiency immune disorder will more than likely be the runt of the litter. Even if size does not appear to be an initial concern, he or she may appear to be the weakling, or just trailing a few steps behind the bunch.  

Such dogs typically show these signs of illness beginning at birth. For a couple of days, they will look like a sickly pup, but then appear to turn around for the better. The pup may soon develop the sniffles, sneezing, and a lot of nasal discharge. The dog may begin to scratch constantly because the skin isn’t being protected due to the immune weakness. Respiratory distress may manifest into a steady cough. Overall, a bunch of seemingly disparate symptoms will soon merge and begin to make sense. When an immune system is non-functional, or struggling beyond its capability to rally and fight a virus, the primary deficit is immunoglobulin A (IgA). Some dogs can move beyond puppyhood, while others cannot survive the relentless infections associated with this immune disorder.

Most dog owners do not know that their dog’s allergies, which are often skin-related (and sometimes incorrectly attributable to food) may instead be linked to a lack of Selective IgA, or some level of deficiency.

Selective IgA Deficiency is a serious immune disorder that occurs when dogs lack a sufficient amount of IgA, the immunoglobulin that protects the health of the respiratory, digestive and reproductive system.

• Chronic respiratory infections
• Digestive system problems
• Atopic dermatitis (scratching/nibbling fur & skin)
• Folliculitis
• Pustules
• Otitis externa
• Sneezing
• Nasal discharge
• Smaller size
• Chronic diarrhea
• Frequent urination
• Bladder infections
• Aspergillosis (mostly fatal)
• Antibiotic resistance
• Death

In humans and in animals, immunoglobulin A (IgA) is the second most plentiful and critical antibody in blood. When the immune system is not functional and strong, it does not produce enough IgA. In some cases, the immune system is unable to produce IgA, whatsoever.

Since the Chinese Shar-Pei, the Irish Setter, the Beagle, and most of the all, the German Shepherd, are far more prone to Selective IgA than other breeds, it is likely a hereditary condition.

The veterinarian will rely on a history of the dog, as well as a description of recent symptoms. If the dog is currently in an infectious phase, and showing symptoms such as scratching, sneezing, nasal discharge, stomach ailments and sores from folliculitis, the vet will typically make a diagnosis through the evaluation of symptoms as well as a blood test. Blood testing should measure serum levels to show a reduced or lack of IgA. Additionally, breed is another diagnostic hint.

Treatment will depend upon the allergies, reactions, autoimmune disorders, and infections to which the dog is most prone. If the veterinarian feels the dog is well enough and comfortable, he or she will work with you to develop a maintenance plan to include food, exercise, sleeping environment, and ongoing care. 

Dogs with IgA deficiency will need consistent medical care to manage symptoms and remain comfortable. The owner must be vigilant and keep an eye on any new or recurring symptoms. Many vets recommend supplements that will help stimulate the production of immunoglobulins.

German Shepherds are often unable to survive puppyhood if plagued by severe infections such as otitis externa and folliculitis. Many times, antibiotic therapy does not address the infection.

Unfortunately, German Shepherds are hit hard by the IgA deficiency, and suffer from difficult conditions such as aspergillosis (a respiratory infection caused by a mold/fungus and is 99% fatal), otitis externa (inflammation of the ear canals), atopic dermatitis (eczema, inflammation of the skin, and weepy sores), and folliculitis (hair follicles infected by bacterial or fungus, leading to carbuncles, boils and lesions). Not only are the infections painful and uncomfortable for the dog, many antibiotics do not resolve the infections.

If an IgA deficient dog is cared for by an owner who is willing to provide consistent medical care, proper food and a low-stress environment, some dogs may still enjoy a quality of life. Of course, it is important to see the veterinarian immediately for acute infections, and on a regular basis for routine care. Additionally, your vet will strongly recommend that the dog be removed from any breeding pool. It is not humane to pass this hereditary condition on to other canines.