Chronic Inflammatory Arthritis – Causes, Symptoms, Treatment

Chronic Inflammatory Arthritis/Psoriatic arthritis (PsA) is chronic inflammatory arthritis associated with psoriasis (PsO) and found in about 20 to 30% of such patients. It shares many clinical features with other spondyloarthropathies and also rheumatoid arthritis (RA). It is usually seronegative, but a small percentage of patients may be positive for rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibodies (anti-CCP antibodies). The clinical manifestations are varied and can change over time, evolving from one articular pattern to another.  There is a considerable financial and psychological burden associated with this disease. There has been significant progress recently in understanding the disease pathogenesis, which has translated into new therapies.[rx]

Types of Chronic Inflammatory Arthritis

The earliest classification of psoriatic arthritis by Moll and Wright included five subtypes:

• Oligoarticular arthritis which is asymmetric and involves less than five small or large joints
• Polyarticular arthritis which is usually symmetric and presents similar to rheumatoid arthritis but may involve the DIP joints, rheumatoid factor negative
• Distal arthritis signified by prominent involvement of the DIP joints
• Arthritis mutilans characterized by a severe destructive joint disease with deformities especially in hands and feet
• Spondyloarthritis pattern with sacroiliitis and spondylitis (this may occur with or without peripheral joint disease)

Types of Psoriatic Arthritis and Their Symptoms

• Symmetric arthritis – Symmetric arthritis occurs in the same joints on both sides of the body. Similar to rheumatoid arthritis (RA), symmetric arthritis symptoms include joint pain, inflammation, and stiffness. However, symmetric arthritis symptoms are usually milder than RA symptoms.
• Asymmetric arthritis – With asymmetric arthritis, many joints can be affected, including the wrist, hip, knee, and ankle, but it doesn’t occur in the same joints on both sides of the body. Symptoms include joint pain that comes and goes, and joints may become warm, tender, and/or red. Some people also develop dactylitis—a condition that causes pain and swelling of the fingers and/or toes. Dactylitis is sometimes referred to as “sausage digit” because when the fingers or toes become inflamed, they can resemble a sausage.
• Distal interphalangeal predominant (DIP) – This type of psoriatic arthritis is pretty rare and is sometimes confused with osteoarthritis (OA). But what distinguishes distal interphalangeal predominant from OA is that it usually involves the finger and/or toe joints closest to the fingernail and/or toenail. (“Distal” means “near” and “phalanges” are fingers and toes, so “interphalangeal” means “between fingers/toes”).
• Spondylitis: Spondylitis – also known as ankylosing spondylitis is inflammation in the spinal column. Common symptoms are inflammation, reduced flexibility, and stiffness in the neck and low back, which can make moving or bend painfully and very difficult to do.
• Arthritis mutilans – This type of psoriatic arthritis is a severe and often destructive form of the condition. It mostly affects the hands and feet, but fortunately, it’s rare.

Symptoms of Chronic Inflammatory Arthritis

The clinical features of psoriatic arthritis are described in terms of articular and extra-articular manifestations.

Articular/periarticular manifestations of psoriatic arthritis

• Peripheral arthritis presenting in an oligoarticular vs. polyarticular pattern
• Periarticular disease including enthesitis (inflammation around the insertion of ligaments, tendons, or joint capsules), dactylitis (swelling of the entire digit, finger or toe, “sausage digit”), and tenosynovitis
• Axial disease involving sacroiliac joints, usually asymmetric and spondylitis with discontinuous involvement with bulky non-marginal syndesmophytes

Extra-articular manifestations of psoriatic arthritis

• Psoriatic skin disease usually presents before the onset of arthritis but can occur simultaneously and even before the onset of joint disease. The severity of skin disease does not correlate well with the severity of the articular disease.[rx]
• Nail disease characterized by onycholysis, pitting, and splinter hemorrhages.  The severity of nail disease correlates with the severity of both skin and joint disease.[rx]  It is present in 80 to 90% of patients with psoriatic arthritis and is associated with DIP joint involvement.
• Ocular disease in the form of uveitis but unlike that associated with ankylosing spondylitis, it is often chronic, bilateral, and often involves posterior elements.

Common Psoriatic Arthritis Symptoms

• Back pain
• Changes to your nails (eg, the nails can begin to separate from the nail bed)
• Decreased range of motion
• Eye pain and eye redness
• Fatigue
• Painful, swollen joints
• Sausage-like swelling of the fingers or toes (although this is more common during the advanced stages)
• Stiffness (especially in the morning)
• Tenderness at the points where muscles and/or ligaments connect to bones, especially the heel and bottom of the foot

Diagnosis of Chronic Inflammatory Arthritis

Lesions suspected of polyarthritis (PsA)

• Early lesions period (0–6 months).

Isotope examination

• – Ultrasound examination of joints found to be abnormal on isotope examination;
• – Hand X-ray (initial radiographs).

MRI

• – In the case of equivocal ultrasound;
• – Lesions involving axial skeleton (CT alternatively).

Later period (over 6 months).

• Monitoring of treatment:

• • • – Ultrasound of abnormal joints;

    • – Scintigraphy/ultrasound/MRI (alternatively) in case of symptoms suggesting the involvement of other joints.

• Follow-up hand X-ray after 2 years.

Advanced lesions

• Bilateral hand X-ray examination (if involved) every 2 years.
• Ultrasound for monitoring activity of the inflammatory process.
• Magnetic resonance imaging in case of axial skeleton involvement.

In the 60’s and 70’s five clinical forms of PsA were distinguished by Moll and Wright:

• The classic course of the disease with involvement of the distal interphalangeal joints (5% of cases).
• The destructive form of arthritis (arthritis mutilans) (5% of cases).
• Symmetric polyarthritis is indistinguishable from rheumatoid arthritis with a negative rheumatoid factor (approximately 15% of cases).
• An asymmetric form involving a few interphalangeal joints (also distal) and metacarpophalangeal joints. It is the most common form of arthritis in psoriasis (approximately 70% of all cases).
• A form resembling ankylosing spondylitis (5% of cases).

A group of diseases with similar clinical manifestations called seronegative spondyloarthropathies (SpA) has also been defined [rx]. The group includes:

• Ankylosing spondylitis (AS).
• Psoriatic Arthritis (PsA).
• Spondylitis with associated bowel disease (or enteropathic spondylitis).
• Reactive arthritis.
• Undifferentiated spondyloarthropathies.

To support the diagnosis of seronegative spondyloarthropathies, the European Spondyloarthropathy Study Group (ESSG) created some clinical criteria. Basing on these criteria the assessment includes the following features:

• Inflammatory back pain.
• Arthritis.
• Positive family history.
• Psoriasis.
• Inflammatory bowel disease.
• Buttock pain.
• Enthesitis.
• Episodes of acute diarrhea.
• Urethritis.
• Sacroiliitis.

The following examinations and tests can help to diagnose psoriatic arthritis and distinguish it from other inflammatory conditions of the joints:

• Physical examination – Certain changes are more typical of psoriatic arthritis. For instance, the inflammation may affect a whole finger (dactylitis) or the tendons and tendon sheaths of the hands or feet, such as the Achilles tendon (enthesitis).
• Blood tests – 90% of people with psoriatic arthritis don’t have any of the antibodies in their blood that is typical of rheumatoid arthritis. So if none of these “rheumatoid factors” are found, it’s more likely to be psoriatic arthritis.
• Measuring uric acid levels – High levels of uric acid in the blood are a sign that the joint problems are being caused by gout rather than psoriatic arthritis.
• Imaging techniques – X-rays and ultrasound scans can help to find out whether someone has psoriatic arthritis, rheumatoid arthritis, or osteoarthritis. The images can also help doctors get an idea of the severity and type of joint damage. But changes in the joints are often not yet clearly visible in the early stages of psoriatic arthritis.[rx, rx, rx, rx]
• Ultrasound – is readily available in the clinics and hospitals and is has utility for a variety of functions, but it has a limited role in polyarticular arthritis for detecting erosions and synovitis. Clinicians can easily perform joint injection under the guidance of ultrasound.[rx][rx] Computed tomography has almost no role other than ruling out other etiologies, and the role of MRI is to pick very early joint inflammation or early bone/soft tissue infection.
• Radionuclide scans  – are rarely done but have specific purposes. Picking up metastases, Paget disease of the bone, and osteomyelitis represent several of these indications.
• Erythrocyte sedimentation rate and C-reactive protein – are non-specific markers of inflammation but usually helpful in ruling in a pathology causing significant inflammation and also monitoring its response to treatment.[9]
• Polarized microscopy – of synovial fluid can help with crystal arthritis diagnoses, such as gout and pseudo-gout. Clinicians also analyze synovial fluid for cell count, gram stain and cultures. Synovial fluid leukocyte counts less than 200/mm are normal, between 200/mm and 2000/mm are associated with non-inflammatory arthritis, and over 2000/mm with inflammatory arthritis. If the cell count is over 50000/mm, physicians should treat the fluid as infectious.[10]

Classification Criteria

The most accepted classification criteria for psoriatic arthritis are the CASPAR criteria (Classification of Psoriatic Arthritis ) which have been in use since 2006.[rx] Other classification criteria that clinicians have used include the original Moll and Wright (1973), Bennet (1979), and Vassey and Espinoza (1984), the modified ESSG (1991) criteria.[rx]

Moll and Wright criteria (1973)[rx]

• Inflammatory arthritis (peripheral arthritis and/or sacroiliitis or spondylitis)
• The presence of psoriasis
• The absence of serologic tests for rheumatoid factor

CASPAR Criteria (2006)[rx]

Clinical features/Characteristics/Points                                 

• Skin psoriasis: present – 2 / previously present -1 / family history, patient not affected – 1
• Nail lesions: onycholysis, pitting, hyperkeratosis – 1
• Dactylitis: present or past, documented by a rheumatologist – 1
• Rheumatoid factor: negative by any method except for latex – 1
• Juxta-articular bone formation: distinct from osteophytes – 1

Per CASPAR criteria, psoriatic arthritis is considered to be present in patients with inflammatory arthritis who have at least 3 points; this has a specificity of 98.7% and a sensitivity of 91.4%.[rx]

Surgical Treatment