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This information is provided by Provet for educational purposes only.

You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.

Autoimmune diseases are common in both human and veterinary patients and they share some common characteristics and possibly common causes

Immune-mediated diseases in which damage is caused to the patients own organs are called "autoimmune" diseases. An official definition of autoimmunity is :

"Autoimmunity is reactivity of the immune system against self-antigens (autoantigens), that is the antigens expressed by normal constituent cells or proteins of the patient"

Some autoimmunity is normal physiological activity - for example old red blood cells express a new antigen on their surface which then stimulates an immune reaction to destroy them. It is only when the immune reaction abnormally damages tissues it is called an autoimmune disease, and these are common in both humans and veterinary patients. They are usually severe and debilitating - or even fatal. 

The precise aetiopathogenesis of autoimmune diseases is not fully understood, but it is now clear that they can occur as a consequence of exposure to infectious agents.

Factors that are thought to be important in the triggering of immune-mediated disease by an infection are :

  • Genetic predisposition in the patient
  • The infectious agent may have similar antigens to the patient (called antigenic mimicry)
  • Inflammation in tissues may increase their sensitivity when exposed to immune cells/substances

The following table summarises some of the immune-mediated diseases in humans and dogs, and whether or not the disease is linked to exposure to an infectious agent (virus, bacteria or parasites) :

Human Infectious Agent Dog Infectious Agent
Guillain-Barre Syndrome Campylobacter jejuni enteritis Polyradiculoneuritis Not confirmed
Insulin Dependent Diabetes Mellitus (IDDM) Coxsackie virus Insulin Dependent Diabetes Mellitus (IDDM) Not confirmed
Rheumatoid Arthritis Proteus mirabilis Rheumatoid Arthritis Not confirmed
Myocarditis Coxsackie virus

?Beta-haemolytic streptococci exhibit antigenic mimicry with myofibres and heart valve fibroblasts

Myocarditis occurs but it is not recognised to be an immune-mediated disorder Direct effect of several agents including parvovirus, canine distemper virus, trypanosomiasis, toxoplasmosis, fungi, algae, rickettsiae
Rheumatic fever Streptococcus pyogenes  Not recognised in dogs  
Ankylosing spondylitis Klebsiella pneumoniae Spondylosis does occur in dogs but it is a non-inflammatory disease  
    Renal Amyloidosis Chronic exposure to infection (eg nocardia, fungal infections, bacterial infections)
    Hypothyroidism Not confirmed
    Immune-mediated haemolytic anaemia Not confirmed
    Immune-mediated thrombocytopenia Not confirmed
    Polyarthritis Not confirmed

?Mycobacterium tuberculosis exhibits antigenic mimicry with proteoglycan in articular cartilage

    Myasthenia gravis Not confirmed
    Inflammatory bowel disease Not confirmed
    Lymphocytic/plasmacytic infiltration of the liver Not confirmed
    Lymphocytic/plasmacytic infiltration of the respiratory tract Not confirmed
    Granulomatous meningioencephalitis Not confirmed


Updated January 2016