Inflammatory, immune mediated disorder of the axial and peripheral joints includes ankylosing spondylitis, psoriatic arthritis, enteropathic arthritis, nonradiographic axial spondyloarthritis, and reactive arthritis.
Spondyloarthritis, refers to a group of disorders that includes Ankylosing Spondylitis (AS), psoriasis arthritis, enteropathic arthritis related to Inflammatory Bowel Disease, and reactive arthritis or post-infectious type.
Spondyloarthritis is characterized by chronic inflammation affecting the axial joints of the spine, pelvis, and thoracic cage, the peripheral joints of arms and legs, or both.
When the axial joints are predominately involved, axial spondylarthritis is the name of the condition, and its prototype is ankylosing spondylitis.
Systemically diseases that are associated with HLA-B27 gene.
The most common extraarticular manifestation of axial spondylarthritis is anterior uveitis, typically associated with HLA-B 27.
In these diseases many clinical features occur at sites outside of the skeleton and peripheral joints.
The most frequent extraarticular manifestations of spondyloarthritis are uveitis, psoriasis and colitis.
The extra-articular manifestations of spondyloarthritis may occur with the presence of HLA-B27, even without axial skeleton or peripheral joint involvement, and suggests a HLA-B27-related systemic disease rather than a simple musculoskeletal disorder.
Peripheral Spondyloarthritis arthritis primarily involves peripheral joints, with its prototype being psoriatic arthritis, characterized by psoriatic skin lesions, synovitis, enthesitis, and dactylitis.
Classification criterion for spondyloarthritis do not require the presence of sacroiliitis on imaging test, as this appears late in the disease.
Criterion enables patients with back pain for more than 3 months and age less than 45 years to be classified as having spondyloarthritis, if, in the presence of HLA B27, there are at least two clinical characteristics related with spondyloarthritis: these features include peripheral arthritis and extraarticular manifestations such as enthesitis, dactylitis, uveitis, psoriasis and colitis.
5 to 10% of patients with spondyloarthritis have Inflammatory Bowel Disease (IBD), including Crohn’s disease or ulcerative colitis.
Cervical myelopathy is the most common disorder of the spinal cord in persons older than 55 years of age.
Reactive arthritis, triggered by antecedent infection, is another spondylarthritis that is typically peripheral.
Radiologic spondylotic changes increase with patient age – 90% of asymptomatic persons older than 70 years have some form of degenerative change in the cervical spine.
Colonoscopic exam in spondyloarthritis patients show silent ileitis or colitis in 30% to 40% of patients.
Hiistologic examination of spondyloarthritis patients reveals microscopic inflammation in up to 60% of patients.
The link between IBD and spondyloarthritiss is consistent with the fact that patients with IBD often have peripheral arthritis or sacroiliitis.
In patients with IBD, 30% have inflammatory back pain and 18% had asymptomatic sacroiliitis.
A CARD15 gene polymorphism is common in patients with inflammatory bowel disease, and is also more prevalent in spondyloarthritis that has intestinal involvement
For patients with IBD the prevalence of this polymorphism is higher in patients who have sacroiliitis.
IBD and spondyloarthritis considered part of a same group of diseases.
Factors such as HLA-B27 could be responsible for differentiation into a specific form of disease.
Despite the prevalence of colitis in patients with spondyloarthritisis, colonoscopies should be performed in patients who have abdominal pain, diarrhea or blood in the stool.
Only 6% of spondyloarthritis with subclinical intestinal involvement will evolve to IBD.
Control of peripheral arthritis may be associated with the resolution of the inflammatory bowel disease.
Arthritis occurs in 9 to 53% of patients with IBD.
Arthritis is more common in cases involving the large intestine, compared with the involvement of the small intestine.
There are two types of presentation of arthritis in patients with IBD: type 1 oligoarticular, in large joints, with acute inflammation, and type 2 polyarticular and more chronic disease, that does not match bowel inflammation symptoms.
Uveitis is manifestation of extra-articular spondyloarthritisis that is typically acute, anterior and recurrent.
In psoriasis and IBD, uveitis may have a chronic course, can be bilateral and may involve the posterior uveal tract
Acute anterior uveitis is found in the conjunctival limbal region with a contracted pupil and ocular pain.
If untreated, inflammation in the anterior chamber may become very important, even leading to the appearance of hypopyon
In patients with HLA-B27 uveitis, spondyloarthritis is the disease responsible for about 50% of cases.
Considering the frequency of systemic diseases in patients with uveitis, these patients should be evaluated by a rheumatologist.
Uveitis is more often associated with ankylosing spondylitis
Uveitis strongly correlated with the presence of HLA-B27.
With uveitis and arthritis, one should also consider infectious diseases in differential diagnosis such as tuberculosis, Lyme disease, syphilis and HIV, and other systemic inflammatory diseases such as sarcoidosis, vasculitis, juvenile idiopathic arthritis and relapsing polychondritis.
Enthesis refers to the insertion of ligaments or tendons on bone surface and it has a fibrocartilaginous structure.
Enthesis is a complex mechanical structure that comprises the tendon, the adjacent bone, fibrocartilaginous structures, bursae, synovium and fat pad.
All of these structures are commonly affected in enthesitis.
The plantar and calcaneal tendons, and ligaments of the costochondral joints, the tibial tuberosity, iliac crest and greater trochanter of the femur are involved in enthesitis.
Enthesitis clinically is characterized by pain and swelling on the site.
Many patients whose are HLA-B27 positive have enthesitis in the absence of sacroiliitis.
Enthesitis does not occur exclusively in spondyloarthritis , but also in arthritis caused by calcium pyrophosphate deposition and in rheumatoid arthritis.
Cutaneous manifestations in spondyloarthritis include oral ulcers, erythema nodosum, pyoderma gangrenosum, keratoderma blennorrhagica and psoriasis.
Psoriasis is a common cutaneous manifestation in spondyloarthritis.
In psoriasis skin lesions predate joint condition in three quarters of the cases, which facilitates the diagnosis, and in a smaller percentage of cases, the musculoskeletal picture may precede the skin lesions.
Patients with psoriasis and spondyloarthritis often have more peripheral arthritis.
Although psoriatic arthritis occurs in 20 to 30% of patients with cutaneous psoriasis, the involvement of the sacroiliac joints and spine occurs only in about 5% of patients.
Spondyloarthritis treatments with anti-TNF agents can induce the appearance of psoriasiform skin lesions.
Osteoporosis is a well-established complication of spondylitis, related to increased chronic inflammatory cytokines and restriction of mobility secondary to pain and loss of range of motion.
Chronic increase in proinflammatory cytokines such TNF as occurs in ankylosis spondyloarthritis inhibit the proliferation and maturation of osteocytes and stimulates osteoclastogenesis but does not prevent the formation of syndesmophytes.
Anti-TNF alpha is effective in controlling the inflammatory activity in spondylitis but does not result in inhibition of progression of syndesmophytes.
TNF, also blocks DKK1, an inhibitor of the wingless signaling, inducing the maturation of osteocytes and allowing osteoproliferation.
Life expectancy is reduced in patients with severe ankylosis spondyloarthritis, and cardiovascular events are responsible for that.
Aortic regurgitation, atrioventricular block and other cardiovascular manifestations can occur in AS as in other types of spondylo arthritis.
Transesophageal echocardiograms shows some degree of change in aortic valve or the aortic root in 82% of patients with ankylosing spondyloarthritis.
Aortic involvement in spondyloarthritis is usually restricted to the ascending aorta and aortic arch, and tends to occurs late in the disease.
Atherosclerosis and peripheral vascular disease are more prevalent in patients with AS and psoriatic arthritis.
Pulmonary involvement with apical pulmonary fibrosis has been described in AS, which can cause pneumothorax.
Lung fibrosis found in AS is subclinical and is rare.
Urogenital manifestations rarely occur, and include infectious urethritis, especially those caused by Chlamydia trachomatis, which trigger cases of reactive arthritis.
The incidence of uveitis is reduced in AS when using an anti-TNF agent.
The expression of TNF is higher in aqueous humor of patients with uveitis.
In IBD, the occurrence of flares of ileitis or colitis was much lower with the use of infliximab compared to etanercept or placebo.
All of the above disorders associated with familial clustering, and related to HLA-B27 in a percentage of patients.
Usually appears in the second and third decades.
The different diseases differ in types of tissue inflammation and structural damage resulting in variety of disease phenotypes.
Spondyloarthritis Is divided into two separate subgroups-axial and peripheral-according to the predominant location of the arthritis.
In axial spondyloarthritis the main clinical symptoms is inflammatory back pain and patients have involvement of the sacroiliac joints, the spine, or both.
In peripheral spondyloarthritis patients have symptoms predominantly localized to peripheral joints, however both may occur.
Axial spondyloarthritis is the classic form of the disease and presents as ankylosing spondyloarthritis or nonradiographic axial spondyloarthritis.
Ankylosing spondylitis presents with characteristic x-ray damage and nonradiographic axial spondyloarthritis presents without radiographic changes but with sacroiliac joint information on MRI or CT scan.
Extra articular manifestations that include inflammatory bowel disease, uveitis/iritis, aortic insufficiency, and enthesitis are observed and can affect the prognosis.
Patients with axial spondyloarthritis are at an increased risk for cardiovascular and other comorbidities, including ischemic heart disease, hypertension, diabetes, osteoporosis, and AV block.
Axial spondyloarthritis symptoms vary but typically manifest in late adolescence or early adulthood.
Patients with axial spondylarthritis experience continuous pain, stiffness and fatigue.
Axial spondylarthritis results in progressive loss of spinal mobility and function if not treated.
The prognosis of axial spondylarthritis is variable and can be affected by the number of extra spinal manifestations, age at diagnosis, and treatment applied.