What is Navigating Immune-Mediated Polyarthritis? Symptoms, Treatment, and Management

A condition of joints caused by the immunity system in canines, immune-mediated Polyarthritis or IMPA can cause pain and inflammation in dogs and cats.

One of the most common joint diseases seen in canines, immune-mediated arthritis can result in causing pain, swelling, and complication of movements.

In the case of IMPA, the immune system is wrongly triggered to transmit white blood cells to multiple body joints. Then the white blood cells discharge chemicals and enzymes into the fluid of the joints, messing up the defensive role of this fluid.

Though a disease of canines, immune-mediated Polyarthritis is typically seen more in dogs than cats but can happen in both.

There are many signs and symptoms of the disorder that you can observe before taking your dog to the vet. Along with that, there are ways to treat and control the effects of immune-mediated Polyarthritis. And with this comprehensive guide on IMPA in canines, you can learn how to help out your furry friend.

Image by Caity from Pixabay Copyright 2016

1. Immune-Mediated Polyarthritis: A 6-Step Comprehensive Guide

First, you must understand the disease to determine the best plan and procedure for treating immune-mediated Polyarthritis. Starting with the definition, you must learn to observe the signs and symptoms, oversee the diagnosis process, and finally find a proper and effective treatment plan.

1.1) What is Immune-Mediated Polyarthritis?

Immune-mediated Polyarthritis is a disorder of the joints that is one of the most common diseases in canines – both dogs and cats. While IMPA is seen more in dogs, it can also be found in cats.

The disorder is caused by a reaction formed by the canine’s immune system, thus named so. When the resistance in such animals is triggered at the wrong time, it releases white blood cells in the joints.

These white blood cells provide chemicals and enzymes to the fluids linking the body’s joints. This wrongly timed event causes a disturbance in the normal defensive function of the joint fluid.

The consequence is an inflammatory response that induces pain, swelling, and movement difficulty.

Put, immune-mediated Polyarthritis is a canine version of rheumatoid arthritis that can be seen in humans.

Human Arthritis
Image by Septimiu Balica from Pixabay Copyright 2020

1.2) Different Types

Polyarthritis caused by malfunctioning of the body’s resistance or immune system is of many kinds.

To understand what kind of ailment your pet is suffering from, you have to be able to distinguish between the various types of IMPA disorders they could be suffering from. The most notable four kinds of IMPA are:

i) Idiopathic Polyarthritis

Idiopathic Polyarthritis, or primary disease, is dogs’ most predominant immune-mediated Polyarthritis. It makes up around sixty-five percent of the known patients. Unfortunately, there is no proven explanation for idiopathic disease.

ii) Breed-Associated Polyarthritis

There is a concept that Polyarthritis is more common in some specific breeds of dogs than others. Among them, you will find the names of Boxer, Weimaraner, and Akita. The most probable reason behind such occurrences is likely genetics and heredity.

Dogs of smaller sizes and miniature breeds are believed to be more susceptible to the disease than the more significant kinds.

iii) Reactive Polyarthritis

Canines with secondary or reactive Polyarthritis frequently have systemic ailments, like gastrointestinal disease, pancreatitis, inflammatory bowel disease, and bacterial, fungal, and viral infections. Consuming specific medications like sulfonamides can also make your dog more vulnerable to such disorders.

iv) Systemic Lupus Erythematosus or SLE

Breeds with canine systemic lupus erythematosus or SLE generate autoantibodies against varied cell structures, which impacts elevated levels of immune complexes.

This circumstance impacts many organs in the body. The body’s most severely affected components are the skin, kidneys, joints, and, most significantly, the central nervous system.

Cat and Dog
Image by JackieLou DL from Pixabay Copyright 2017

1.3) The Signs and Symptoms of IMPA

Without identifying the indications of IMPA, you will not be able to take your pet to the veterinarian in time.

So it is essential to observe and recognize all the clinical signs and symptoms in canines. Along with joint pain and swelling, there are more indications of IMPA in dogs and cats.

i) Swollen Joints and Inflammation

The most seen and common sign is swollen joints along with aches.

This will make the patient unwilling to move and show evidence of constant pain. Even the simplest movements and steps will be painful due to joint swelling.

So the first way to recognize a sign of IMPA is to look for swollen, achy, or painful joints.

ii) Joint Pains

Along with swollen and painful joints, overall pains throughout the body are a common indication of immune-mediated Polyarthritis.

Such pains will make even basic movements difficult and unbearable. So, consulting a medical professional is advised if your cat or dog shows signs of joint or spinal pain.

iii) Difficulty in Movements

When your furry friend, who used to wag their tail happily only with a mention of a walk, is now reluctant even to make the basic movements – you know something is wrong. A complete physical examination at the clinic should always follow the difficulty walking with pets.

iv) Tiredness

When your easily excitable and playful buddy shows lethargy or exhaustion, it is a big red flag.

Immediately take them to the vet to find out if there is any underlying cause of this unusual tiredness.

Tiredness and Difficulty in Movements
Source: Depositphotos

v) Fever

A low-grade fever is believed to be among the earliest symptoms. Whenever your pet shows elevated temperature, make sure to consult the vet to find if there are any underlying causes for the fever.

In most cases with fever, various blood works are done to ensure no serious complications like cancer or severe infection.

Once the possibility of infection is ruled out, a canine is one step closer to getting diagnosed with IMPA.

vi) Anorexia or Lack of Appetite

Anorexia, or decreased appetite, is a sure cause of worry when seen in cats or dogs. If a bowl of their tasty treat fails to excite them, you must consult a medical professional immediately.

Lack of appetite in cats or dogs can result from many things, and not all of them are serious or a cause to worry. But to rule out the more serious possibilities, it is always advised to get a consultation at the veterinary clinic if your pet has a poor appetite.

You may even observe your pet crying out when you try to put on its collar or flinch away when you try to pet them. All these are some of the most vital and prominent signs and symptoms of immune-mediated Polyarthritis.

In the first stages of the disease, the patient may initially present with signs such as a low-grade fever and a lack of appetite. It is your job and responsibility to take the best care of your pet and consult a vet at the earliest indication of any such symptoms mentioned here.

1.4) Most Common Ways to Diagnose

After identifying the significant symptoms of immune-mediated Polyarthritis, you must get a proper diagnosis by consulting a doctor or medical professional.

After a veterinarian discovers joint inflammation and fever, several tests will be done to find the underlying cause behind the patient’s illness. Among them, these tests will be done:

  • Blood Tests
  • Examining for any infectious disease
  • Chest and Joint X-rays and Radiographs
  • Ultrasounds with imaging
  • Joint Taps

The last test, joint tap, take fluid from joints to correctly determine the disorder’s nature.

According to the College of Veterinary Medicine, Cornell University, when the joint fluid of a dog or a cat with Polyarthritis is examined, a myriad of neutrophils having violet and deep blue globules can be observed in their cytoplasm. This makes diagnosis more straightforward.

Along with low platelet count, Anaplasma platys can be identified as specked blue morulae in the platelets when tested.

If the blood tests and cultures do not show any sign of infection, the patient is diagnosed with autoimmune Polyarthritis. This only happens when the immune system malfunctions and mistakenly attacks the parts of the body.

The body’s resistance erroneously attacks the joints, causing pain, inflammation, swelling, and difficulty in mobility.

Canine Arthritis
Source: Depositphotos

This disorder is more commonly diagnosed in aged canines, smaller species, and miniature breeds.

1.5) The Best and Most Effective Treatments for IMPA

After recognizing the symptoms and completing a proper diagnosis, the penultimate step in this procedure is finding the best and most effective treatment plans.

In the case of general infectious or bacterial Polyarthritis, the cure comes from antibiotics.

For IMPA, the approach is slightly different. There are multiple beneficial ways to treat IMPA in canines after the veterinarian detects joint inflammation in a dog.

i) Immunosuppressive Therapy

Those with the condition are treated with medicines that soothe the immune reaction of their body. Such prescriptions involve steroid treatments like prednisone. Many times such medications are given with additional immune-suppressing drugs.

The motive is to turn off the incorrect immune response of the body, and the most effective way to do that is by steroid treatments.

As mentioned, prednisone is one of the most common and beneficial drugs. It is a corticosteroid hormone that successfully suppresses the system’s immune response.

Source: Depositphotos

ii) Nonsteroidal anti-inflammatory drugs or NSAIDs

NSAIDs are generally successful in only milder cases. Most of the time, dogs will need immunosuppressive medications, as mentioned earlier.

Since many believe a non-steroid approach is safer, NSAIDS is first used to treat IMPA. But it is seen to be making no progress; doctors change the treatment plan.

The following strategy is to start immunosuppressive therapy, but only after leaving a gap of around two months after medicating the patient with NSAIDs.

iii) Doxycycline Trials

In areas where it is seen that tick-borne polyarthritis is prominent, veterinarians can advise beginning a doxycycline trial before commencing immunosuppressive treatment.

If a favorable reaction is observed within the first week, the therapy should continue for four weeks.

iv) Melatonin

You might find some theories that melatonin can benefit those with immune-mediated disorders. However, there is no conclusive proof that melatonin is helpful or safe for immune-mediated disease canines.

Even though there are experiments where melatonin has been observed to affect treating the disease positively, there is no concrete evidence.

No matter what, do not start any experimental therapy without the approval of your general veterinarian. In most cases, the immunosuppressive approach works fine, and there is no need to try any controversial methods.

Thorough monitoring and adjustment of the dosage are critical while this treatment is done. It is also crucial to look for common side effects during this therapy.

  • Enhanced appetite and thirst
  • Increase in urine volume
  • Anxiety in the form of pacing and panting
  • General restlessness

Such side effects are primarily seen in the very first stages of treatment. Generally, with an adjustment of dosage, these effects lessen and ultimately end.

Routine tests and analyses are to be done to determine the effectiveness of the treatment. The main objective is finding the minimum dosage to curb the disease successfully. That can only be done by gradually decreasing the dose and seeing if the medicines can be stopped entirely after ongoing a long treatment.

Whatever the case and diagnosis may be, you must remember to always consult your veterinarian before doing anything – starting or stopping medication or treatment. If the procedure is stopped halfway, the condition might worsen, increasing the likelihood of a relapse.

There is no miracle cure. It is more than likely that the patient will be suffering from the disorder for the rest of their life. However, the symptoms can be treated and controlled to a large extent. And with proper therapy and care, the patient can function and live normally. Some may even need lifelong medications to control IMPA but manage to live a happy and healthy life.

Irreversible trauma to joints is a rare occurrence in the patients of IMPA and is rarely heard of. Even though some of them end up needing lifelong treatment to prevent a relapse, side effects due to the treatments are generally negligible and most of the time tolerable and can be controlled. Like other immune-mediated disorders, IMPA also needs active checkups, utmost care, and frequent visits to a veterinarian.

2. FAQs

Do you have more questions about IMPA in dogs and cats? Read on to find the answers to the most frequently asked questions on canine immune-mediated Polyarthritis.

2.1) What is Immune-Mediated Polyarthritis?

This is a joint disorder found in canines caused when the immune system mistakenly attacks the body instead of defending it.

In this case, the attacks occur in the form of chemicals and enzymes released by white blood cells in the joint fluids of the patient. Due to this release, the immunity system of canines ends up acting in total opposite to their original job. Instead of protecting the body, it attacks parts of the body – in this case, the joints.

Seen in both dogs and cats (though the disorder is much more common in the former species), immune-mediated Polyarthritis is the canine version of what is known as rheumatoid arthritis in human beings.

2.2) What are some of the most common symptoms and best ways to diagnose IMPA?

Some general signs and symptoms characterize IMPA, like every disease and disorder. The most common indications of the illness include swelling or inflammation of joints, continuous pain or aches, difficulty in movements, fever, lack of appetite, and sedentary behavior or unusual exhaustion.

Whenever you encounter any or multiple of the following symptoms, the best course is to consult a veterinarian or a medical professional.

When diagnosing your cat or dog, leaving the matter in the capable hands of a medical professional is advisable. For the diagnosis process, tests and examinations will be performed to determine the cause of your pet’s sickness and rule out things such as severe infection or cancer. Among the tests used to diagnose IMPA, you will find blood tests, radiographs or X-rays, ultrasounds, and joint taps.

Only when the possibility of infectious diseases or any other underlying infection is ruled out will your pet be diagnosed with autoimmune Polyarthritis in dogs and cats.

Puppy and Kitten
Image by JackieLou DL from Pixabay Copyright 2017

2.3) What are the best treatment options?

To date, the most effective treatment procedure for IMPA is the application of immune-suppressing therapy. In this method, steroids curb the body’s resistance that attacks the system instead of protecting it.

The most effective and beneficial medications have been found through numerous clinical and laboratory findings that have been applied accordingly.

The best and most used drug for this procedure is prednisone, a corticosteroid hormone. With proper dosage and monitoring, such treatment can even cure your canine of IMPA mostly.

However, it is of utmost importance that you contact your veterinarian at every step of the method. Any mistake, like stopping the dosage too early, will end up making the condition much worse.

2.4) How common is immune-mediated Polyarthritis in cats and dogs?

Even though it can be seen in cats and dogs, the disorder is more typically detected in the latter.

The most common kind of IMPA is considered to be idiopathic Polyarthritis which is around sixty-five percent of the cases. Other factors that can cause IMPA. Among such aspects include the age, size, and breed of the canine. For example, dogs of smaller sizes and breeds especially the miniature kinds are more susceptible to this disorder. Similarly, canines that are older and of more advanced years are more likely to suffer from this disease of joints.

Closing Thoughts: Understanding and Treating IMPA

Immune-mediated Diseases such as IMPA can negatively influence the pet’s and its owner’s average life. Constant pain, inflamed joints, and difficulty in moments can become miserable.

Cats and Dogs
Source: Depositphotos

And seeing your dear companion in pain is never an option. So if you ever observe any indication of the given symptoms, immediately contact a medical professional and take your pet to veterinary care.

Last Updated on December 26, 2023 by