What Is Immune-Mediated Disease In Dogs

In a condition known as immune-mediated thrombocytopenia (ITP), the body’s immune system targets and kills its platelets.

In the condition known as immune-mediated hemolytic anaemia (IMHA), the body’s defence mechanisms target and kill its red blood cells.

An underlying cause of the immune system’s deterioration cannot be found because it is a primary disease. In contrast, secondary immune-mediated thrombocytopenia or immune-mediated hemolytic anaemia happens when the immune system unintentionally kills its own platelets or red blood cells as a result of an immune attack meant to treat an underlying condition like cancer, infection, or exposure to specific drugs or toxins.

It is essential to treat the anaemia or low platelet count in addition to the underlying cause.

Dogs typically develop ITP and IMHA, and the majority of affected canines are middle-aged females. In cats, primary ITP and IMHA are incredibly uncommon. Cats show no breed or sex preference.

Clinical Signs

The symptoms are brought on by a significant, frequently rapid loss of platelets or red blood cells.

Red blood cells play a crucial role in transporting oxygen from the lungs to all other bodily tissues. The body runs out of oxygen when there are not enough red blood cells in the body (anaemia).

You might observe:

Depression
Listlessness
Panting
a diminished appetite
Weakness
unwillingness to exercise

The main job of platelets is to assist in the formation of blood clots that stop bleeding. Large amounts of platelets can be destroyed, which can cause nosebleeds or small areas of bleeding in the skin or gums.

Blood can less frequently be found in the faeces or pee. Excessive bleeding might cause severe anaemia. Immune-mediated thrombocytopenia and immune-mediated hemolytic anaemia happen at the same time in about 50% of cases.

Diagnosis

Evaluation of blood smears, complete blood counts, chemical panels, and urinalyses are necessary for the diagnosis of ITP or IMHA.

It is frequently required to perform specialised blood tests, such as a Coombs test and titers for specific tick-borne infections. Since red blood cells and platelets are produced in the bone marrow, a bone marrow aspirate or biopsy may be necessary in individuals whose bone marrow function is in doubt.

It is frequently essential to rule out an underlying disease (such as cancer) that may have caused the issue, such as radiography (X-rays) and ultrasounds.

Treatment

In order to treat ITP and IMHA, the immune system’s assault on red blood cells and platelets, respectively, must be suppressed.

Prednisone, a steroid, is the medicine that is most frequently prescribed. This medication’s side effects include:

higher appetite
increased urination and thirst
elevated anxiety (pacing, panting and restlessness)

Until there is test proof that the anaemia has subsided and the breakdown of red blood cells or platelets has stopped, treatment must be continued. Blood testing and repeated examinations will be necessary to track the effectiveness of the therapy in this situation.

Prednisone dosage can be gradually tapered off if the immune system has been sufficiently subdued, frequently over the course of many months.

Finding the lowest dose of medication that controls the condition is the objective. Ideally, drugs can be totally stopped. It is crucial to perform many follow-up exams to gauge how well the treatment is working. Additional drugs could be recommended if the immune system is not sufficiently suppressed.

In some dogs and cats, the loss of platelets or red blood cells might be so great that a potentially fatal anaemia can develop. It may be required to stabilise these animals with blood transfusions until the bone marrow can manufacture enough cells to meet the demand and until the immune system-suppressing drugs have had time to take effect.

Prognosis

The prognosis for both illnesses varies greatly and is based on the underlying aetiology of the illness. The prognosis may also be affected by complications from the illness or medication treatment.

Some patients with severe disease require lifelong pharmacological therapy, while some patients with severe disease do not respond to treatment.

Relapses can happen months to years after the initial episode and are not uncommon. Recurrence may be caused by vaccinations, drugs, or both.

What canine immune-mediated conditions are there?

Among the canine and feline immune-mediated conditions are:

hemolytic anaemia that is immune-mediated.
thrombocytopenia that is immune-mediated.
polyarthritis that is immune-mediated.
Grave myasthenia
inflammation of the colon.
autoimmune skin condition.
Meningoencephalitis with granuloma.
“Dry Eye,” or keratoconjunctivitis sicca

What signs are there of canine autoimmune disease?

Dogs are most frequently affected by this, which assaults the joints and results in an inflammatory reaction with the following clinical signs:

unwillingness to walk.
a limp or altered gait.
Several painfully inflamed joints.
Fever.
Lethargy.
Inappetance (lack of appetite) (lack of appetite)
nausea or diarrhoea

What are diseases that are immune mediated?

The term “immune-mediated disorders” refers to a range of conditions caused by aberrant immune cell activity. These conditions include overreacting or attacking the body, exhibiting a severe inflammatory response, or losing the ability to detect and combat malignancy cells. Immune-mediated disorders include systemic lupus erythematous, rheumatoid arthritis, Takayasu syndrome, type 1 diabetes, allergies, and cancer. These entities’ causes have been attributed to host variables, as well as environmental and lifestyle situations. In contrast to host variables like inheritance, gender, race, and age, environmental factors include things like viruses, bacteria, radiation, environmental pollution, and dietary components. The genetic complexity underpinning the body’s dysfunctional immune system activity has been shown in the endeavour to uncover the genetic causes of immune-mediated diseases. In addition, it has been documented how common risk factors contribute to the development of these entities. These investigations have also helped to identify prospective treatment targets with useful information. Providing an updated review of the genetic, genomic, and epigenetic components, as well as the genetic-environmental interactions involved in immune-mediated illnesses and the identification of potential new therapeutic targets, is the goal of this special issue. The following themes will be covered under the topic: 1. Epidemiological research and ethnic variations in immune-mediated illnesses such cancer, erythematosus lupus, and arthritis 2. The investigation of polymorphisms and mutations in the nuclear and mitochondrial genome was the subject of association studies. 3. Experimental information advancing our knowledge of the molecular processes underlying the onset of certain disorders 4. Research utilising open access datasets and cutting-edge bioinformatic methods to better understand their genetic origins. 5. Analysis of interactions between genes and their environments. 6. Literature outlining the genetic basis of immune-mediated illnesses.

We also want original research submissions, meta-analyses, and review articles that advance our knowledge of the immunologic disorders’ underlying causes.

Important Reminder

What percentage of dogs with IMHA survive?

One of the most frequent autoimmune diseases to affect dogs is immune-mediated hemolytic anaemia (IMHA), and several elements of its pathophysiology have been well studied.

2, 3 Although these findings are encouraging, the prognosis for dogs with IMHA is still uncertain, with published case fatality rates for canine primary IMHA ranging from 26% to 60%. 4, 5, 6 Various clinicopathologic anomalies have been related in the past with different outcomes in dogs with IMHA. However, few prognostic markers are constant throughout numerous studies, possibly as a result of variations in study populations or a lack of standardisation. It has been indicated that rapid validation and standardisation of diagnostic criteria for canines with IMHA is needed, and that stratification by mortality risk in upcoming interventional clinical studies would be advantageous. 7 Usually, sickness severity scores are used to determine the mortality risk for clinical trials. 8 A complicated scoring system may be necessary for accurate prognostication in the case of a disease process as complex as IMHA. The canine hemolytic anaemia objective score (CHAOS) and a score created in Japan (Tokyo) have both been suggested as such schemes, but neither has undergone an independent assessment to determine whether it is still possible to use them as prognostic indicators outside of the populations from which they were drawn.

The American Society of Anesthesiologists (ASA) health classification and the presence or absence of indicators of a systemic inflammatory response syndrome are alternatives to these disease-specific sickness severity scores that might be simpler to quantify (SIRS). The ASA classification is typically used to assess anaesthetic risk in patients10, but it has also been employed as a measure of disease severity in other canine groups since it is simple to administer. 11 Measurement of acute phase proteins or cytokine concentrations can be used to assess the inflammatory response related to IMHA in dogs. 13 While a SIRS score based on easily accessible clinical data is a more universal way to identify dogs with systemic inflammation, these measurements are not routinely accessible. 14

Recently, a number of studies from various UK hospitals have been published, but each documented only a small number of cases and focused on a different component of the illness. It is challenging to summarise the demographics, treatments, and results of the entire UK canine IMHA population presenting to referral centres, even with the advantage of these data. 15, 16, 17

By reviewing case presentations, management approaches, and treatment outcomes of dogs with IMHA who presented to several referral centres in the British Isles, we hoped to fill in these information gaps in this study. Additionally, we wanted to evaluate the prognostic value of two previously reported IMHA-specific disease severity ratings as well as the relationship between the illness severity indicators ASA and SIRS status and outcome. Using a multivariate analysis methodology, we also sought to isolate independent prognostic markers from our own dataset with the hypothesis that a multivariable scoring system would be more accurate in predicting survival than a single variable alone.

What causes canine autoimmune diseases?

Our immune systems in our bodies defend us against outside invaders that can spread illness and infection. However, if you have an autoimmune disease, your immune system unintentionally assaults you, which can lead to significant sickness. Immune cells attempt to kill healthy tissues because they are unable to discriminate between the body’s regular healthy cells and alien cells. It’s unclear what caused this “error” in the first place. A single system of the body or a number of them may be affected by autoimmune illness. Skin, connective tissues, neurons, muscles, the endocrine system (the system that regulates hormones and other substances), red blood cells, and the digestive system can all be impacted by autoimmune illnesses. Immunizations shouldn’t be given to dogs and cats with autoimmune illnesses unless certain conditions apply. You can talk about this in more detail with your veterinarian.

What causes autoimmune disease?

Uncertainty surrounds the cause or causes of autoimmune disease, while some believe that genetics and/or environmental toxins may be involved. Some dogs may be predisposed to or “triggered” by autoimmune skin illnesses, according to research on ultraviolet (UV) exposure. A frequent type of autoimmune skin disease in dogs and cats called pemphigus foliaceus has also been linked to specific medications as potential causes. Extremely crucial is early detection. If neglected, autoimmune illness can have catastrophic implications that frequently involve many systems. As a result, diagnosis and therapy may be extremely difficult and complicated.

What are some of the common autoimmune skin diseases in dogs?

In dogs, autoimmune skin conditions are quite uncommon. Among the more prevalent types of autoimmune skin conditions are:

Five autoimmune skin conditions collectively known as pemphigus are characterised by vesicles and bullae (big and small “blisters”) at mucocutaneous junctions and in the mouth (the junction between skin and mucosal tissues). The eyelids, lips, nostrils, and anus are frequently impacted locations.

The most prevalent immune-mediated skin illness in dogs and cats is called Pemphigus Foliaceus (PF), which literally translates to “leaf-like pemphigus.” It is uncommon to find Pemphigus foliaceus in the mouth or at mucocutaneous junctions. Crusts (scabs) and ulcers grow around the patient’s eyes, ears, footpads, groyne, and nose bridge when they have this type of pemphigus. The Chow Chow, Akita, Cocker Spaniel, Labrador Retriever, Dachshund, English Bulldog, Finnish Spitz, and Schipperke were the breeds most frequently affected. Pemphigus foliaceus typically manifests without warning and without apparent cause. However, it can occasionally be brought on by drugs or be the outcome of a long-term skin condition.

The most prevalent type of pemphigus in people is called pemphigus vulgaris (PV), which literally translates to “common pemphigus.” Vesicles, which are fluid-filled blisters, develop in and near the mouth, eyes, lips, nostrils, anus, prepuce, and vulva. These vesicles easily rupture, resulting in excruciating ulcers. In dogs, this ailment is uncommon.

Pemphigus erythematosus (PE) is a condition characterised by redness, crusting, scales, and hair loss on the nose. The word means “red and inflamed pemphigus.” This type of pemphigus gets worse when exposed to UV radiation. The German shepherd dog, collie, and Shetland sheepdog are breeds that are predisposed.

Pemphigus vegetans is characterised by thick, atypical vegetal lumps or lesions that are accompanied by persistent pustules and “oozing.” It’s thought to be a milder variation of pemphigus vulgaris. In dogs, this ailment is uncommon.

The least typical (and most severe form of pemphigus) is known as paraneoplastic pemphigus (PNP). This condition is linked to the existence of a malignant tumour underneath.

Although bullous pemphigoid sounds similar to pemphigus, it is a distinct autoimmune skin disease. A big, thin-walled sac that is filled with clear fluid is referred to in medicine as a bullous. Large red welts and hives frequently arise before or during the development of blisters, and the skin is typically quite irritating. In addition to the axillae (armpits) and groyne, vesicles and ulcers can appear in the mouth, at mucocutaneous junctions, and elsewhere. The diagnosis depends heavily on the examination of the vesicles. Vesicles build quickly and break, thus the dog must frequently be hospitalised and monitored every two hours until enough biopsies can be taken. Bullous pemphigoid frequently resolves on its own. In canines and felines, it is regarded as rare.

Systemic lupus erythematosus (SLE), sometimes known as lupus, is a well-known instance of a multi-systemic autoimmune illness. Because it can imitate practically any other disease state, lupus is frequently referred to as the “great imitator.” SLE symptoms typically wax and wane and might be acute (sudden onset) or chronic. One of the defining clinical symptoms of SLE is a fluctuating temperature that does not respond to antibiotics. Along with SLE, leg stiffness or shifting-leg lameness is usually noted. Leukopenia, hemolytic anaemia, low platelet counts, thrombocytopenia, and symmetrical dermatitis, particularly over the bridge of the nose, are some other clinical indicators that may be present (often called a “butterfly lesion”). SLE is thought to be more typical in dogs than cats when it comes to autoimmune skin diseases. Without first consulting your veterinarian, vaccinations shouldn’t be given to dogs or cats who have SLE. The Shetland sheepdog, collie, German shepherd dog, Old English sheepdog, Afghan hound, beagle, Irish setter, and poodle are only a few of the breeds mentioned in the literature.

Uncommon in cats, discoid lupus erythematosus (DLE) is another inflammatory skin condition that affects canines. Despite the fact that it can affect various breeds, the term “Collie nose” is another prevalent appellation for this ailment. Collies, Shetland sheep dogs, German shepherds, and Siberian huskies are the breeds that exhibit DLE the most frequently. Sunlight and UV radiation exposure is considered to be a potential cause or trigger. The pigmentation around the nose is typically lost by affected dogs, while the skin surrounding the lips, eyes, ears, and genitalia may also be affected. The typical “cobblestone” texture of the nose’s surface can be changed by DLE to one that is smooth, flat, and shining. Sores with ulcers can develop. While some dogs find the illness upsetting, others don’t seem to be impacted by it. DLE might be a less severe, non-systemic variation of systemic lupus erythematosus (SLE). It is regarded as an autoimmune skin condition that is often benign.

A skin biopsy of the afflicted area is required to make a conclusive diagnosis of autoimmune skin disease. A local anaesthetic may be used to perform a skin biopsy, depending on the area. Sedation or general anaesthesia may be necessary, though, if the affected area is the nose or face or if the patient is concerned. A tool called a punch biopsy is used to remove a little circular chunk of skin. A veterinary pathologist will next use this tissue sample to make a diagnosis.

How is autoimmune skin disease treated?

Immunosuppression is the main therapy for autoimmune skin disease. This implies that your dog will take medications to lessen or stop the immune system’s reaction that is causing the condition. Prednisone or dexamethasone therapy will be adequate for many dogs. For certain dogs, harsher immunosuppressants such azathioprine, chlorambucil, or oral cyclosporine are necessary. Antibiotics and medicated baths will be administered if secondary bacterial infections are present. The ideal course of therapy will be decided by your dog’s veterinarian.

What is the prognosis for autoimmune skin disease?

The severity of the symptoms and the precise diagnosis for the autoimmune skin disease in your dog will determine the prognosis.

Generally speaking, this is a potentially fatal ailment needing rigorous diagnostic procedures and therapies. Even while autoimmune disease is rarely cured, the right medicine can frequently make it manageable.