Juvenile rheumatoid arthritis is a progressive destructive and inflammatory joint lesion in children that developed before the age of 16 and is combined with extra–articular pathology. The articular form of the disease is manifested by edema, deformation, contracture of large and small joints of the extremities, the cervical spine; the systemic form is accompanied by common symptoms: high fever, polymorphic rash, generalized lymphadenopathy, hepatosplenomegaly, heart, lung, kidney damage. The diagnosis is based on the data of the clinical picture, laboratory examination, radiography and joint puncture. In this disease, NSAIDs, glucocorticosteroids, immunosuppressants, exercise therapy, massage, physiotherapy are prescribed.
ICD 10
M08.0 Juvenile rheumatoid arthritis
Meaning
Juvenile rheumatoid arthritis is a diffuse connective tissue disease with predominant joint damage that develops in childhood and adolescence. Disease is the most common disease in pediatric rheumatology. According to statistics, it is diagnosed in 0.05-0.6% of young patients worldwide. Usually, the pathology does not manifest itself before the age of two, while it is 1.5-2 times more common in girls. Arthritis refers to disabling rheumatic pathology, often leads to disability at a young age.
Causes
Presumably, the development of pathology is caused by a combination of various exogenous and endogenous damaging factors and hypersensitivity of the body to their effects. Manifestations can be facilitated by:
- acute infection, (most often, viral, caused by parvovirus B19, Epstein-Barr virus, retroviruses);
- joint injury;
- insolation or hypothermia;
- injections of protein preparations.
Potentially arthritic stimuli can be collagen proteins (types II, IX, X, XI, oligomeric matrix protein of cartilage, proteoglycans). An important role is played by a family genetic predisposition to the development of rheumatic pathology (carrying certain sublocuses of HLA antigens).
Pathogenesis
One of the leading links in the pathogenesis of juvenile rheumatoid arthritis is a congenital or acquired immune disorder that leads to the development of autoimmune processes. In response to the influence of the causal factor, modified IgG (autoantigens) are formed, which produce autoantibodies – rheumatoid factors. Being a part of circulating immune complexes, the RF triggers a number of chain pathological reactions that lead to damage to the synovial membrane and vascular endothelium, the development of non-purulent chronic inflammation of an exudative-alterative, and then proliferative nature in them.
There is the formation of microvilli, lymphoid infiltrates, growths of granulation tissue (pannus) and erosions on the surface of articular cartilage, destruction of cartilage and bone epiphyses, narrowing of the articular gap, atrophy of muscle fibers. Progressive fibrotic-sclerotic joint damage occurs in children with seropositive and systemic variant of juvenile rheumatoid arthritis; leads to irreversible changes in the joints, the development of subluxations and dislocations, contractures, fibrous and bone ankylosis, limitation of joint function. Destruction of connective tissue and changes in blood vessels are also manifested in other organs and systems. Juvenile rheumatoid arthritis can also occur in the absence of rheumatoid factor.
Classification
Juvenile rheumatoid arthritis is an independent nosological unit that resembles rheumatoid arthritis in adults, but differs from it in articular and extra-articular manifestations. The classification of the American College of Rheumatologists identifies 3 variants of juvenile rheumatoid arthritis:
- system
- polyarticular
- oligo- (pauci-) articular (types I and II). Type I oligoarthritis accounts for up to 35-40% of cases of the disease, mainly girls are ill, the debut is at the age of 4 years. Type II oligoarthritis is observed in 10-15% of patients, mainly in boys, the onset is at the age of over 8 years.
According to immunological characteristics (the presence of rheumatoid factor), juvenile rheumatoid arthritis is divided into seropositive (RF +) and seronegative (RF-). According to clinical and anatomical features, there are:
- articular form (with or without uveitis) in the form of polyarthritis with a lesion of more than 5 joints or oligoarthritis with a lesion of 1 to 4 joints;
- articular-visceral form, including Still syndrome, Wissler-Fanconi syndrome (allergoseptic);
- form with limited visceritis (heart, lung, vasculitis and polyserositis).
The course of juvenile rheumatoid arthritis can be slow, moderate or rapidly progressive. There are 4 degrees of activity of juvenile rheumatoid arthritis (high – III, medium – II, low – I, remission – 0) and 4 classes of the disease (I–IV) depending on the degree of dysfunction of the joints.
Symptoms of juvenile rheumatoid arthritis
Articular form
In most cases, the JURA begins acutely or subacutely. Acute onset is more typical for generalized articular and systemic forms of the disease with a recurrent course. With a more common articular form, mono-, oligo- or polyarthritis develops, often of a symmetrical nature, with the predominant involvement of large joints of the extremities (knee, wrist, elbow, ankle, hip), sometimes small joints (2nd, 3rd metacarpophalangeal, proximal interphalangeal).
There are swelling, deformation and local hyperthermia in the affected joints, moderate pain at rest and during movement, morning stiffness (up to 1 hour or more), limited mobility, gait changes. Small children become irritable, may stop walking. There are cystic formations, hernial protrusions in the area of the affected joints (for example, a cyst of the popliteal fossa). Arthritis of small joints of the hands leads to fusiform deformation of the fingers. Juvenile rheumatoid arthritis often affects the cervical spine (pain and stiffness in the neck) and the TMJ (“bird’s jaw”). Hip joint damage usually develops in the later stages of the disease.
There may be subfebrility, weakness, moderate splenomegaly and lymphadenopathy, weight loss, growth retardation, elongation or shortening of limbs. The articular form of juvenile rheumatoid arthritis is often combined with rheumatoid eye damage (uveitis, iridocyclitis), a sharp drop in visual acuity.
Rheumatoid nodules are characteristic of the RF-positive polyarthric form of the disease occurring in older children, having a more severe course, the risk of developing rheumatoid vasculitis and Sjogren’s syndrome. RF-negative juvenile rheumatoid arthritis occurs in any childhood, has a relatively mild course with rare formation of rheumatoid nodules.
System form
The systemic form is characterized by pronounced extra-articular manifestations: persistent febrile fever of a hectic nature, polymorphic rash on the limbs and trunk, generalized lymphadenopathy, hepatolienal syndrome, myocarditis, pericarditis, pleurisy, glomerulonephritis.
Joint damage can manifest itself in the initial period of systemic juvenile rheumatoid arthritis or a few months later, while taking a chronic recurrent course. Still’s syndrome is more often observed in preschool children, it is characterized by polyarthritis with damage to small joints. Wissler-Fanconi syndrome usually occurs at school age and proceeds with the dominance of polyarthritis of large, including hip joints without pronounced deformities.
Complications
Complications of juvenile rheumatoid arthritis are secondary amyloidosis of the kidneys, liver, myocardium, intestines, macrophage activation syndrome with a possible fatal outcome, cardiopulmonary insufficiency, growth retardation. Type I oligoarthritis is accompanied by chronic iridocyclitis with the risk of vision loss, type II oligoarthritis is accompanied by spondyloarthropathy. The progression of juvenile rheumatoid arthritis leads to persistent deformation of the joints with partial or complete restriction of their mobility and early disability.
Diagnostics
Diagnosis of juvenile rheumatoid arthritis is based on the data of anamnesis and examination of the child by a pediatric rheumatologist and a pediatric ophthalmologist, laboratory tests (Hb, ESR, presence of RF, antinuclear antibodies), radiography and MRI of joints, joint puncture (arthrocentesis). The criteria for juvenile rheumatoid arthritis are:
1 Debut before the age of 16.
2 The duration of the disease is more than 6 weeks.
3 The presence of at least 2-3 signs:
- symmetrical polyarthritis,
- deformities of small joints of the hands,
- destruction of joints,
- rheumatoid nodules,
- positivity in the Russian Federation,
- positive synovial membrane biopsy data,
- uveit.
The radiological stage of juvenile rheumatoid arthritis is determined by the following signs:
- I – epiphyseal osteoporosis;
- II – epiphyseal osteoporosis with narrowing of the articular gap, single marginal defects (usures);
- III – destruction of cartilage and bone, numerous usures, subluxations of joints;
- IV – destruction of cartilage and bone with fibrous or bony ankylosis.
Differential diagnosis is performed with juvenile ankylosing spondylitis, juvenile psoriatic arthritis, reactive and infectious arthritis, Bekhterev’s disease, Reiter’s disease, SLE, inflammatory bowel diseases (Crohn’s disease, Whipple’s disease), bone tumors, acute leukemia.
Treatment of juvenile rheumatoid arthritis
Treatment of YURA is long and complex, begins immediately after diagnosis. During the period of exacerbation, motor activity is limited (running, jumping, active games are excluded), it is forbidden to stay in the sun. In nutrition, restrictions relate to salt, proteins, carbohydrates and fats of animal origin, sweets. It is recommended to eat food with a high content of vegetable fats, fermented dairy products with low fat content, fruits, vegetables, taking vitamins of group B, PP, C.
Drug therapy of juvenile rheumatoid arthritis includes symptomatic (anti-inflammatory) drugs of rapid action and pathogenetic (basic) means, physiotherapy:
- in the acute period of articular syndrome, NSAIDs (diclofenac, naproxen, nimesulide) are prescribed
- if necessary, glucocorticosteroids (prednisone, betamethasone) are used orally, topically and intra-articularly or in the form of pulse therapy.
- prescribe basic drugs-immunosuppressants (methotrexate, sulfasalazine).
- an important component of the therapy of juvenile rheumatoid arthritis is physical therapy, massage, physiotherapy (medicinal phonophoresis, mud, paraffin, ozokerite applications, UVI, laser therapy) and treatment with natural factors.
Complex therapy can reduce the need for symptomatic drugs, prevent progression, prolong remission and improve the prognosis of juvenile rheumatoid arthritis. With pronounced joint deformities and the development of severe ankylosis, joint prosthetics is indicated.
Prognosis and prevention
Juvenile rheumatoid arthritis is a lifelong diagnosis. With adequate treatment and regular supervision of a rheumatologist, a long-term remission is possible without pronounced deformities and loss of joint function with a satisfactory quality of life (study, work by profession). The risk of exacerbation may persist for many years. A more unfavorable prognosis with early onset, continuously recurrent course, RF + polyarthritic and systemic forms of juvenile rheumatoid arthritis, leading to the development of complications, severe limitations of movement in the joints and disability.
To prevent exacerbations of juvenile rheumatoid arthritis, it is necessary to avoid insolation, hypothermia, climate change, limit contacts with infectious patients, exclude preventive vaccinations and the use of immunostimulants.
