Introduction
Presentation
Juvenile idiopathic arthritis (JIA) is the most common chronic arthritis of children. It is one of the most common chronic illnesses of childhood and a major cause of short- and long-term functional disability and eye disease leading to blindness. JIA is the term used throughout this article in preference to juvenile rheumatoid arthritis (JRA).1
Although it has been customary to refer to JIA as 1 disease, it is almost certainly 3 or more diseases, which may have the same cause, different causes, or a closely related series of host responses. The course of JIA is unpredictable. The course tends to be most predictable after the pattern of the disease is established.
In 1864, Cornil first suggested the idea that inflammatory polyarthritis can occur in childhood, describing a 29-year-old woman who had had chronic inflammatory arthritis since the age of 12 years. In 1890, Diamant-Berger commented on the acute onset of disease, the predominant involvement of large joints, a course characterized by exacerbation and remission, the frequent disturbances of normal growth, and the generally good prognosis.Demographics
Depending on location of the study and criteria, the prevalence is 86.1-94 cases per 100,000 population, and the incidence is 11.7 cases per 100,000 population per year.
Juvenile idiopathic arthritis is more common in Norway and Australia than in other countries. In Norway, the prevalence is 148.1 cases per 100,000 population, and the incidence is 22.6 cases per 100,000 population.
The disease-associated mortality is difficult to quantify, but it is estimated to be less than 1% in Europe and less than 0.5% in North America. Most deaths associated with juvenile idiopathic arthritis in Europe are related to amyloidosis, and most in the United States are related to infections.
- The major causes of morbidity in patients with JIA are related to functional disability, therapeutic complications, and psychosocial problems.
- Amyloidosis is the major cause of mortality
Hanson and colleagues suggest that in North America, rates of juvenile idiopathic arthritis are proportionately lower in African-American children than in white children.2 Some reports suggest that JIA is less frequent in African populations than in European populations. However, in Nigerian Africans, the proportion of patients with onset of chronic inflammatory arthritis in childhood may be somewhat high.
Twice as many girls as boys develop juvenile idiopathic arthritis.
- Girls with an oligoarticular onset outnumber boys by a ratio of 3:1.
- In children with uveitis, the ratio of girls to boys is 5-6.6:1.
- Among children with polyarticular onset, girls outnumber boys by 2.8:1.
- In striking contrast, systemic onset occurs with equal frequency in boys and girls.
Although juvenile idiopathic arthritis is defined as arthritis beginning before age 16 years, the age at onset is often young, with the highest frequency in children aged 1-3 years.3
- This age distribution is most evident in girls with oligoarthritis and less so in those with polyarticular onset.
- The frequency of systemic onset is not increased at any particular age.
- In boys, a second peak occurs at age 8 years.
Presentation and natural history
Pertinent historical features are listed below.
- Systemic onset - Classic systemic or Still disease
- Systemic onset is usually seen in boys and girls younger than 5 years.
- This form accounts for 20% of all cases of JIA.
- Patients may have an acute febrile onset with severe and remittent fever.
- Toxic symptoms of irritability, listlessness, anorexia, and weight loss may be observed.
- Macular or maculopapular rash is found in 80-90% of patients.
- Hepatosplenomegaly and generalized lymphadenopathy may be noted.
- Patients may have pericarditis, myocarditis, pleuritis, and amyloidosis.
- Joint manifestations are generally mild.
- Oligoarthritis - Pauciarticular
- The persistent form occurs when 4 or fewer joints are involved during the course of disease.
- The extended form is when 5 or more joints are involved after the first 6 months of disease.
- Oligoarthritis accounts for about 30-70% of all cases of JIA.
- Oligoarthritis is generally confined to large joints, most frequently the knee, ankle, elbow, and wrist joints.
- This disease poses a serious threat of blindness from iridocyclitis.
- Polyarthritis
- RF-positive disease accounts for 10% of all cases of JIA.
- RF-negative disease accounts for 30% of all cases of JIA.
- Polyarticular disease
- Five or more joints are involved.
- Rates are equal in boys and girls.
- Symmetric or asymmetric involvement of the proximal interphalangeal (PIP), metacarpophalangeal (MCP), metatarsophalangeal (MTP), wrist, and ankle joints is typical. The usual clinical picture at onset is early involvement of 5 or more of these joints.
- Cervical spine is frequently affected.
- Juvenile-onset adult-type RF-positive (seropositive) rheumatoid arthritis
- This is more common in girls than in boys.
- This disease most commonly occurs after age 10 years.
- The clinical onset is usually polyarticular (>5 joints), with early involvement of the interphalangeal (IP), MCP, MTP, knee, and wrist joints.
- Severe destructive arthritis is common and occurs in 50% of patients.
- Subcutaneous elbow nodules are observed in 10-20%.
- The prognosis is poor.
- Enthesitis-related juvenile-onset ankylosing spondylitis
- Boys may have sacroiliitis and spondylitis with positive results for HLA-B27.4
- Asymmetric arthritis of the lower extremity may be observed.
- The mean age at onset os 10-12 years.
- Iridocyclitis affects 25% of patients.
- Patients may have a positive family history of ankylosing spondylitis or disease related to HLA-B27 in a first- or second-degree relative.
- The radiographic abnormalities are virtually indistinguishable from those of adult-onset ankylosing spondylitis.
- Psoriatic arthritis
- Patients may have a positive family history of psoriasis in a first-degree relative.
- The age of onset is variable but usually 9-10 years.
- Nail abnormalities may be the initial clinical manifestations.
- Asymmetric articular involvement with periods of remission and exacerbation are mostly characteristic.
- Occasional patients have chronic iridocyclitis.
- A slight female preponderance is reported.
Criteria and classification
Three sets of criteria are used to classify JIA: those developed by the American College of Radiology (ACR), those of the European League against Rheumatism (EULAR), and those proposed by the International League of Associations for Rheumatology (ILAR).5,6,7
The ACR criteria define arthritis, the age limit (<16 y), and the duration of disease (>6 mo) necessary for a diagnosis. They also recognize 3 types of onset: polyarticular, pauciarticular, and systemic.
The EULAR proposed the term juvenile chronic arthritis (JCA) for the heterogeneous group of disorders that manifest as juvenile arthritis. The diagnosis requires that the arthritis begins before the age of 16 years, that it lasts for at least 6 weeks, and that other diseases are excluded.
The ILAR criteria are currently the preferred classification system. The aim is to provide a unified classification system. The ILAR classification of JIA includes the following features:
- Systemic onset
- Persistent or extended oligoarthritis
- Rheumatoid factor (RF)–positive polyarthritis
- RF-negative polyarthritis
- Psoriasis
- Enthesitis
- Other: The disease does not meet criteria for any of the other subgroups, or it meets more than 1 criterion (and therefore could be classified in a number of subgroups).
The etiology and pathogenesis of juvenile idiopathic arthritis are unclear despite numerous investigations. JIA may represent not a single disease but a syndrome of diverse causes.
Both abnormal immune regulation and cytokine production may play a role.8 levels of circulating immune complexes in JIA have parallel activity with disease and systemic features.
JIA is most assuredly a complex genetic trait. The various forms of JIA have nonmendelian inheritance, and interactions of several genes are likely important in these diseases.9,10
Arthritis is associated with the clinical course of many viral diseases, such as rubella, parvovirus B19, and influenza A.11,12,13,14
Complications in juvenile idiopathic arthritis can be divided into skeletal and extraskeletal.
Skeletal complications include the following:
- Joint destruction, which may require prosthetic surgery
- Osteopenia
Plain radiograph of the knee shows osteopenia with enlargement of the distal femoral epiphysis. Epiphyseal overgrowth is thought to result from chronic hyperemia.
Widespread osteopenia, carpal crowding (due to cartilage loss), and several erosions affecting the carpal bones and metacarpal heads in particular in a child with advanced juvenile idiopathic arthritis (JIA).
- Atlantoaxial subluxation
- Cervical vertebral ankylosis
Ankylosis in the cervical spine at several levels due to long-standing juvenile idiopathic arthritis (JIA).
- Vertebral compression fracture
- Micrognathia
- Brachydactyly
- Limb lengthening or shortening
- Carpal ankylosis
Widespread osteopenia, carpal crowding (due to cartilage loss), and several erosions affecting the carpal bones and metacarpal heads in particular in a child with advanced juvenile idiopathic arthritis (JIA).
Extraskeletal complications include the following:
- Uveitis
- Pancarditis
- Nephritis
- Mesenteric thrombosis
- Peripheral neuropathy
- Digital arteritis
- Cutaneous ulcers
- Raynaud phenomenon
- Myocardial infarction
- Muscle atrophy
- Lymphedema
- Malnutrition
Related eMedicine Radiology topics:
Rheumatoid Arthritis, Hands
Rheumatoid Arthritis, Spine
Osteoarthritis, Primary
Psoriatic Arthritis
Reactive Arthritis, Musculoskeletal
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Differential Diagnoses
| Caffey Disease | Osteomyelitis, Chronic |
| Eosinophilic Granuloma, Skeletal | Osteoporosis, Involutional |
| Osteoarthritis, Primary | Pigmented Villonodular Synovitis |
| Osteomyelitis, Acute Pyogenic | Spondylodiskitis |
More on Juvenile Rheumatoid Arthritis |
 Overview: Juvenile Rheumatoid Arthritis |
| Imaging: Juvenile Rheumatoid Arthritis |
| Multimedia: Juvenile Rheumatoid Arthritis |
| References |
| Further Reading |
| Next Page » |
References
Cassidy JT, Petty RE. Textbook of Pediatric Rheumatology. 4th ed. Philadelphia, Pa: WB Saunders; 2000.
Hanson V, Kornreich HK, Bernstein B, et al. Three subtypes of juvenile rheumatoid arthritis (correlations of age at onset, sex, and serologic factors). Arthritis Rheum. 1977;20 (Suppl):184.
Sullivan DB, Cassidy JT, Petty RE. Pathogenic implications of age of onset in juvenile rheumatoid arthritis. Arthritis Rheum. May-Jun 1975;18(3):251-5. [Medline].
Berntson L, Damgård M, Andersson-Gäre B, Herlin T, Nielsen S, Nordal E, et al. HLA-B27 predicts a more extended disease with increasing age at onset in boys with juvenile idiopathic arthritis. J Rheumatol. Oct 2008;35(10):2055-61. [Medline].
Cassidy JT, Levinson JE, Bass JC, Baum J, Brewer EJ Jr, Fink CW. A study of classification criteria for a diagnosis of juvenile rheumatoid arthritis. Arthritis Rheum. Feb 1986;29(2):274-81. [Medline].
Johnson K, Gardner-Medwin J. Childhood arthritis: classification and radiology. Clin Radiol. Jan 2002;57(1):47-58. [Medline].
Prieur AM, Ansell BM, Bardfeld R, Bhettay E, Bojkinov I, Denieskiewics K. Is onset type evaluated during the first 3 months of disease satisfactory for defining the sub-groups of juvenile chronic arthritis? A EULAR Cooperative Study (1983-1986). Clin Exp Rheumatol. May-Jun 1990;8(3):321-5. [Medline].
De Benedetti F, Ravelli A, Martini A. Cytokines in juvenile rheumatoid arthritis. Curr Opin Rheumatol. Sep 1997;9(5):428-33. [Medline].
Grom AA, Giannini EH, Glass DN. Juvenile rheumatoid arthritis and the trimolecular complex (HLA, T cell receptor, and antigen). Differences from rheumatoid arthritis. Arthritis Rheum. May 1994;37(5):601-7. [Medline].
Prahalad S, Glass DN. A comprehensive review of the genetics of juvenile idiopathic arthritis. Pediatr Rheumatol Online J. Jul 21 2008;6:11. [Medline].
Jarvis JN. Pathogenesis and mechanisms of inflammation in the childhood rheumatic diseases. Curr Opin Rheumatol. Sep 1998;10(5):459-67. [Medline].
Lang BA, Shore A. A review of current concepts on the pathogenesis of juvenile rheumatoid arthritis. J Rheumatol Suppl. Mar 1990;21:1-15. [Medline].
Petty RE, Tingle AJ. Arthritis and viral infection. J Pediatr. Nov 1988;113(5):948-9. [Medline].
Pritchard MH, Matthews N, Munro J. Antibodies to influenza A in a cluster of children with juvenile chronic arthritis. Br J Rheumatol. Jun 1988;27(3):176-80. [Medline].
McHugh K, Gupta R, Murray K. Imaging in juvenile chronic arthritis. Imaging. 1999;11:91-7.
Pedersen TK, Küseler A, Gelineck J, Herlin T. A prospective study of magnetic resonance and radiographic imaging in relation to symptoms and clinical findings of the temporomandibular joint in children with juvenile idiopathic arthritis. J Rheumatol. Aug 2008;35(8):1668-75. [Medline].
Gylys-Morin VM. MR imaging of pediatric musculoskeletal inflammatory and infectious disorders. Magn Reson Imaging Clin N Am. Aug 1998;6(3):537-59. [Medline].
Lamer S, Sebag GH. MRI and ultrasound in children with juvenile chronic arthritis. Eur J Radiol. Feb 2000;33(2):85-93. [Medline].
Argyropoulou MI, Margariti PN, Karali A, Astrakas L, Alfandaki S, Kosta P, et al. Temporomandibular joint involvement in juvenile idiopathic arthritis: clinical predictors of magnetic resonance imaging signs. Eur Radiol. Oct 29 2008;[Medline].
Lee EY, Sundel RP, Kim S, Zurakowski D, Kleinman PK. MRI findings of juvenile psoriatic arthritis. Skeletal Radiol. Nov 2008;37(11):987-96. [Medline].
Workie DW, Graham TB, Laor T, Rajagopal A, O'Brien KJ, Bommer WA, et al. Quantitative MR characterization of disease activity in the knee in children with juvenile idiopathic arthritis: a longitudinal pilot study. Pediatr Radiol. Jun 2007;37(6):535-43. [Medline].
Nistala K, Babar J, Johnson K, Campbell-Stokes P, Foster K, Ryder C, et al. Clinical assessment and core outcome variables are poor predictors of hip arthritis diagnosed by MRI in juvenile idiopathic arthritis. Rheumatology (Oxford). Apr 2007;46(4):699-702. [Medline].
Shanmugavel C, Sodhi KS, Sandhu MS, Sidhu R, Singh S, Katariya S, et al. Role of power Doppler sonography in evaluation of therapeutic response of the knee in juvenile rheumatoid arthritis. Rheumatol Int. Apr 2008;28(6):573-8. [Medline].
Further Reading
AAOS clinical guideline on osteoarthritis of the knee.
American Academy of Orthopaedic Surgeons
American Association of Neurological Surgeons
American College of Physical Medicine and Rehabilitation
American College of Rheumatology. 1996 (revised 2003). 17 pages. NGC:003069
Ophthalmologic examinations in children with juvenile rheumatoid arthritis.
American Academy of Pediatrics. 2006 May 1. 3 pages. NGC:004963
Anakinra for rheumatoid arthritis.
National Institute for Health and Clinical Excellence (NICE) - National Government Agency [Non-U.S.]. 2003 Nov. 19 pages. NGC:004809
Keywords
juvenile rheumatoid arthritis, juvenile idiopathic arthritis, JIA, juvenile chronic arthritis, JCA, JRA, rheumatoid factor, RF
