What is Inflammatory Arthritis?
Arthritis is a condition that causes painful inflammation and stiffness of the joints. It can come in two main types: inflammatory arthritis, which involves inflammation, and non-inflammatory arthritis, which doesn’t. The first step in figuring out how to best help a patient is to determine which type of arthritis they have.
Inflammatory arthritis typically comes with classic signs of inflammation. These signs can include pain, redness (erythema), warmth, swelling, and a loss of function, although not all these signs may be present in every case. Inflammatory arthritis can have different causes, both infectious and non-infectious. It may or may not come with additional signs related to the specific underlying condition that’s causing the inflammatory arthritis.
If it’s left untreated, inflammatory arthritis almost always leads to joint damage and deformities. So it’s really important that any suspected instances of arthritis get checked out by a doctor as soon as possible to prevent any further complications.
What Causes Inflammatory Arthritis?
Inflammatory arthritis can have several causes, including:
1. Infectious or septic arthritis: This is when harmful organisms led to arthritis-like Staphylococcus aureus, Streptococcal pneumoniae, Neisseria gonorrhea, among others. It’s usually caused by one type of organism. Sometimes more than one type of organism can cause it especially if there’s trauma (an injury) that affects a joint. Infections from gram-negative bacteria usually happen after a physical injury or in people who use intravenous drugs.
2. Crystalline arthritis: This type is arthritis is caused by crystals forming in your joints. It includes types like gout, pseudogout, and basic calcium phosphate (BCP) disease. Gout is when there’s an overproduction or under-excretion of uric acid, which leads to the deposition of monosodium urate crystals in the joint. Pseudogout happens when calcium pyrophosphate crystals deposit in the cartilage, leading to inflammation. Most instances of this are idiopathic, meaning the cause is still unknown. However, it can be linked to problems with calcium, phosphorus, or magnesium metabolism, or conditions like familial chondrocalcinosis and hemochromatosis. BCP is rare and usually associated with hypothyroidism and diabetes.
3. Autoimmune inflammatory arthritis: This is a broad category which has many types, all involved with the body’s immune system mistakenly attacking your own tissues. It includes:
* Rheumatoid arthritis – there can be seropositive (detection of autoantibodies in blood) or seronegative (without autoantibodies).
* Juvenile idiopathic arthritis – it occurs in children and cause is still unknown.
* Seronegative spondyloarthritis – There are many diseases in this group all related to a specific gene HLA-B27. Diseases include psoriatic arthritis, ankylosing spondylitis, reactive arthritis etc.
* SAPHO syndrome – This involves a variety of conditions, namely, synovitis (inflammation of the membrane that lines the joints), acne, pustulosis (formation of pustules), hyperostosis (excessive growth of bone), and osteitis (bone inflammation).
* Arthritis associated with underlying connective tissue diseases or autoimmune diseases – arthritis is common in several autoimmune diseases like systemic lupus erythematosus, drug-induced lupus, Sjogren syndrome, mixed connective tissue disease, systemic sclerosis, inflammatory myopathies, Behcet’s disease, vasculitis etc.
Severe or systemic cases of these conditions can cause arthritis. Lastly, arthritis can be a common symptom of underlying cancers and is often associated with a condition called palmar fasciitis and polyarthritis syndrome which is often linked with ovarian cancer.
Risk Factors and Frequency for Inflammatory Arthritis
Each year, early inflammatory arthritis affects between 115 to 271 adults per 100,000, while undifferentiated inflammatory arthritis affects between 41 to 149 adults per 100,000. Several patients with undifferentiated inflammatory arthritis may later develop rheumatoid arthritis or remain with undifferentiated arthritis. Approximately 70% of these patients can be diagnosed with a specific type of arthritis at the time of their first medical evaluation, with rheumatoid arthritis being the most common diagnosis.
- Of the various types of arthritis, gout is the most common inflammatory arthritis, while rheumatoid arthritis is the most common autoimmune inflammatory arthritis.
- While women are more prone to most types of autoimmune inflammatory arthritis, such as rheumatoid arthritis, systemic lupus erythematosus, and Sjogren syndrome, gout, and seronegative spondyloarthritis, are more usual in men.
- The age at which arthritis presents can vary. For example, juvenile idiopathic arthritis usually appears before the age of 10, numerous autoimmune inflammatory arthropathies generally emerge in early adulthood, and late onset is common in both autoimmune inflammatory arthropathies and paraneoplastic inflammatory arthritis.
Signs and Symptoms of Inflammatory Arthritis
Inflammatory arthropathies, or joint inflammations, can largely be classified based on a person’s medical history and a physical examination. Symptoms may come on suddenly, as with infectious or crystalline arthropathies, or evolve gradually, as with most autoimmune inflammatory arthropathies. Some important factors to consider include how abruptly the symptoms came on, the number of joints involved, whether it affects the body symmetrically, and the distribution and pattern of the inflammation.
- Infectious arthritis: Typically affects one joint and is especially common in previously injured joints or the lower extremities, such as the knees. Lyme disease, for example, often causes sudden inflammation of the knee.
- Crystalline arthropathies: Can affect one joint, a few, or multiple joints.
- Autoimmune inflammatory arthropathies: Usually affect multiple joints. However, it may start with a single or a few joints before spreading to others.
- Rheumatoid arthritis: Commonly involves the small joints of the hands and feet, but usually leaves the spine and the end joints of the fingers unaffected.
- Virus-related arthritis: Tends to impact multiple joints and can sometimes resemble rheumatoid arthritis. Viruses such as Hepatitis B, Hepatitis C, and Parvovirus B19 are examples.
- Gout: Initially, acne-like inflammation of a joint in the big toe is common in 50% of cases. Ultimately, this joint is involved in 90% of gout cases.
- Pseudogout: Mainly affects the knees, wrists, and some finger joints.
- Basic calcium phosphate disease: Frequently involves the shoulders.
- Inflammatory arthritis accompanying other body-wide conditions like systemic lupus erythematosus typically presents with other clinical signs such as skin rashes, while systemic sclerosis may cause the skin to harden and tighten, a condition known as sclerodactyly, and Sjögren syndrome often comes with dry eyes and mouth.
Knowing these features can provide insights into the possible causes of a person’s inflammatory arthritis.
Testing for Inflammatory Arthritis
For conditions related to inflammation in the joints, various laboratory tests are typically carried out. These may show increased levels of markers indicating inflammation in your body, such as the erythrocyte sedimentation rate and C-reactive protein. Signs like increased platelet count and chronic disease-related anemia can also often be noted. When joint inflammation is linked to an infection, a higher white blood cell count is common, whereas a lower count might suggest an infection paired with an autoimmune disease, like lupus. People with gout, a form of arthritis, might also show abnormal kidney function as they are often prone to chronic kidney disease.
The level of uric acid in the blood can also become elevated in patients with gout. However, during a gout flare-up, uric acid could appear lower than usual which could be misleading. If pseudogout is suspected, which is caused by underlying conditions like high calcium levels, an overactive parathyroid gland or iron overload, the laboratory tests might show abnormalities related to these diseases. If an autoimmune disorder might be causing joint inflammation, specific tests would be conducted. For example, people with rheumatoid arthritis often show reactions for rheumatoid factor or anti-cyclic citrullinated peptide antibodies, while those with other autoimmune conditions like lupus or scleroderma may have positive results for autoantibodies such as antinuclear antibody and antibodies to double-stranded DNA or Anti-Smith, among others.
Another crucial part of the diagnostic process is the analysis of the synovial fluid, the lubricating fluid in your joints. This would involve testing the fluid for cell counts, using a polarized light microscope to check for crystal formations, taking and analyzing a sample for bacterial growth, as well as looking for fungus which might be causing the infection. Generally, the cell count in the synovial fluid is under 2000 cells/mm3 in cases of non-inflammatory arthritis and more than 5000 cells/mm^3 in inflammatory arthritis. Extremely high cell count or high presence of a type of white blood cell called neutrophils usually indicate an infection in the joint, although it might also suggest flare-ups of gout or pseudogout. Depending on the kind of arthritis, the synovial fluid can show a predominance of different types of cells. Needle-shaped uric acid crystals will be visible under a polarized light microscope if you have gout. On the other hand, rhomboid-shaped, weakly birefringent calcium pyrophosphate crystals are found in pseudogout.
Imaging tests like x-ray, MRI, CT scans, ultrasound, and nuclear medicine joint scans, help the doctors to evaluate the inflammation. Standard x-rays can spot signs of inflammation around the joint, erosion of the bone near the joint, or show calcium deposits in the case of pseudogout. Entheseal calcifications, that is the hardened areas where tendons or ligaments insert into the bone could be observed with seronegative spondyloarthritis, a group of disorders causing inflammation in the spine and other joints. In case of early axial spondyloarthritis, commonly affecting the lower back, initial x-rays might seem normal. However, progression of the disease may lead to the appearance of a bamboo spine and sacroiliac joint fusion and erosions. An MRI can be of great help when x-rays are inconclusive as it provides a more detailed view of the synovium, the soft tissue lining the joint, bone erosions, sacroiliitis an inflammation of the sacroiliac joint, with a sensitivity far greater than x-rays. CT scans, although not usually very informative in evaluating inflammatory arthritis, can be employed to detect chondrocalcinosis or erosion of bones, when these are not evident in x-rays. Ultrasound of the musculoskeletal region proves extremely beneficial in evaluating peripheral inflammatory arthritis, and can be further used to guide the process in joint aspirations for diagnostics. Nuclear medicine joint scan is not always preferred due to high sensitivity but otherwise low specificity. However, it does come in handy when evaluating the presence of inflammation or infections in artificial joints.
Treatment Options for Inflammatory Arthritis
In simple terms, inflammation can be reversed, but damage to your joints cannot. If detected and treated early, further damage and physical disability may be prevented.
Septic arthritis, a dangerous joint infection, needs immediate treatment as delaying or leaving it untreated can permanently damage the joint and lead to other serious conditions like sepsis. After examining the fluid in your joint, you’ll be given antibiotics that work against a wide range of bacteria. Later, doctors can adjust this based on lab results from your fluid analysis to target specific bacteria. In certain cases, joint washing or an orthopedic evaluation may be needed. Prosthetic joint infections are complex to treat, often involving the removal of the artificial joint, followed by a course of antibiotics and another surgery to re-insert the artificial joint.
Conditions like gout and pseudogout can resemble septic arthritis. If septic arthritis is ruled out and gout or pseudogout is confirmed, anti-inflammatory medicines like corticosteroids, NSAIDs, or colchicine will be used. For patients who suffer frequent gout attacks or those diagnosed with gout who also have kidney disease, or exhibit tophi (hard, uric acid deposits under the skin) or bone erosion, doctors may recommend medicines to lower urate levels in your body.
For patients with autoimmune inflammatory arthritis, it’s crucial to get early treatment to control inflammation and prevent repeat episodes, disease progression, and joint damage. Treatment choice depends on the underlying cause. Initial treatment often involves conventional disease-modifying drugs such as methotrexate, leflunomide, sulfasalazine, and hydroxychloroquine. If these fail, biological disease-modifying drugs may be used. Regular check-ups and lab tests will be necessary while undergoing this treatment. The main aim of treatment is to achieve a significant reduction of disease activity within three months.
Frequently, a combination of conventional disease-modifying drugs will be used to control the disease more effectively. Long-term use of corticosteroids is generally not recommended due to potential side effects, and corticosteroids should ideally be reserved for managing disease flare-ups.
Surgery is rarely required in the early stages of inflammatory arthritis, but may be considered in patients with long-lasting physical changes due to chronic autoimmune inflammatory joint diseases such as rheumatoid arthritis. An approach involving coordinated care from different healthcare professionals, patient education, physical and occupational therapy, as well as lifestyle and dietary modifications can greatly improve a patient’s quality of life.
What else can Inflammatory Arthritis be?
It’s essential to be able to tell the difference between two types of arthritis: inflammatory and non-inflammatory. The most common type of non-inflammatory arthritis is osteoarthritis. This form of arthritis usually begins gradually and gets worse over time. There are certain joints that are more typically affected by osteoarthritis, which include:
- The knees
- The hips
- The lower part of the spine
- The first joint connecting the toes to the foot
- The finger joints
- The joint connecting the hand to the thumb
Repeated use of or injuries to these joints can cause other areas like the shoulders, elbows, ankles, and wrists to also be affected. The severity of the arthritis can be the same in all joints (symmetric) or different (non-symmetric). You might be able to feel changes in the size of the bones in your hands and feet. These joints may be tender or appear swollen, but they typically do not look red or feel warm. When doctors analyze the fluid within the joints, the results show it is non-inflammatory. A X-ray of your joints might show common signs of osteoarthritis like loss of space in the joint and bone spurs. It’s rare, but sometimes, the joints in the fingers that connect to the hand can have a specific kind of erosion called “gull-wing” in severe cases of osteoarthritis.
What to expect with Inflammatory Arthritis
The outcome for people with arthritis largely depends on what caused it. Two types of arthritis, called septic arthritis and crystal-induced arthritis, can often be treated successfully if caught early. However, if treatment is delayed or the arthritis is misdiagnosed, this can lead to the wearing away of your joints and irreversible damage. This is particularly true for septic arthritis, which can be severe.
For those with rheumatoid arthritis or seronegative spondyloarthritis – types of arthritis that affect the spine and other joints – starting treatment early and aggressively can prevent significant complications in the future, such as wearing away of the joints and changes to the shape of joints.
The outlook for arthritis caused by underlying illnesses that affect the network of tissues that support your body’s organs and tissues, called connective tissue disorders, depends on the specific disorder causing it.
Possible Complications When Diagnosed with Inflammatory Arthritis
Problems can occur in septic arthritis when treatment is delayed or the condition is misdiagnosed; it could potentially cause harsh, long-lasting damage to the joint. Chronic gout, rheumatoid arthritis, and a condition that tests negative for rheumatoid factor but causes inflammation in the spine (seronegative spondyloarthritis) may be linked with destructive changes and damage to the joints. This can disrupt daily activities.
These conditions could lead to:
- Delay in treatment of septic arthritis
- Misdiagnosis of septic arthritis
- Aggressive and permanent joint damage from untreated septic arthritis
- Destructive changes to the joints due to chronic gout, rheumatoid arthritis, and seronegative spondyloarthritis
- Interference with daily functions due to joint damage
Preventing Inflammatory Arthritis
Patients suffering from conditions like gout, which involves crystals forming in the joints, often need to understand more about their diet and lifestyle choices that can help manage the condition. Those with long-term inflammations in their joints frequently require medications that suppress the immune system. It’s important these patients are aware not only of the benefits these medicines can provide, but also the potential side effects they may experience.
Additionally, these patients need to get regular check-ups to monitor their condition and the effects of the medication. Regular exercise plays a crucial role in managing their condition and maintaining overall wellness. Hence, they should understand and appreciate its significance in their treatment and management plan.
