What Is Selective IgA Deficiency?
Selective IgA deficiency is an immune system disorder that occurs due to a lack of IgA (immunoglobulin A) immunoproteins. It is the most common primary immune deficiency disorder in both humans and dogs.
Functions Of An Immune System
The immune system produces these proteins in response to the presence of antigens such as bacteria, viruses, and toxins. Antibodies recognize and attack antigens by binding to them and remove them from the body.
The Importance of IGA
Immunoglobulin A (IgA) is the second most abundant antibody in human blood and is found on the skin, in the respiratory, digestive and reproductive tracts, and in tears. When the immune system fails to produce a sufficient amount of IgA or does not produce it at all, animals have chronic, recurrent respiratory infections, digestive system disorders, dermatitis, and allergies.
The IgA deficiency in the German Shepherd has been associated with severe infections, such as aspergillosis (almost 100% mortality rate), otitis externa, atopic dermatitis, and folliculitis. These infections are generally unresponsive to antibiotic therapy.
Susceptible Dog Breeds
Signs & Symptoms
In puppies, the disease manifests as scratching, sneezing, nasal discharge, chronic diarrhea, and frequent urination.
The IgA deficiency is usually diagnosed through a blood test which may show reduced or absent IgA.