Juvenile idiopathic arthritis in Child
Alerts and Notices
SynopsisJuvenile idiopathic arthritis (JIA, previously known as juvenile rheumatoid arthritis or juvenile chronic arthritis) is a group of illnesses of unknown etiology characterized by the development of arthritis (joint inflammation) in children aged younger than 16 years lasting longer than 6 weeks. JIA is divided into distinct disorders distinguished by age of onset, location and number of joints affected, related symptoms, genetic predisposition, and associated serologies. Untreated, JIA may result in permanent contractures, limb length disparity, growth retardation, need for joint replacement, and blindness.
The most widely adopted classification criteria for JIA is shown below, and it is based mostly on clinical presentation rather than disease pathophysiology. Attempts at incorporating biologic data into new classification criteria are underway, and may help to provide more homogeneous disease subsets in the future. Genetic factors are being investigated within subsets of these diseases.
- Oligoarthritis (fewer than 5 joints involved) – The most common type of JIA, seen in girls aged 2-4 years, it usually affects the lower extremities. This type of arthritis is often complicated by asymptomatic uveitis, a potentially sight-threatening condition; the presence of a positive ANA increases this risk.
- Rheumatoid factor (RF)-positive polyarthritis (5 or more joints involved) – Usually affects adolescent girls; presents with a symmetric arthritis of small joints (wrists and fingers) and a positive RF serology. This disease is the same as adult rheumatoid arthritis.
- RF-negative polyarthritis (5 or more joints involved) – A heterogeneous group; can have positive ANA and behave like oligoarthritis, or can resemble seronegative rheumatoid arthritis in adults.
- Psoriatic arthritis – Often affects children aged 2-4 years and 9-11 years. It is diagnosed when arthritis is seen in patients with psoriasis, or if there is dactylitis (swelling of a finger), nail pits, or a first-degree family member with psoriasis. Patients with nail, scalp, and inverse (intertriginous) psoriatic skin disease have a higher risk of developing psoriatic arthritis.
- Enthesitis-related arthritis – Usually affects boys aged older than 6 years and is characterized by enthesitis, or inflammation of the entheses (the region where tendons and ligaments insert into bone), commonly at the Achilles tendon or plantar fascia. It is associated with HLA-B27 and is often called seronegative spondyloarthropathy.
- Systemic arthritis – This disorder is characterized by the presence of arthritis and quotidian fevers, usually occurring at night, as well as an evanescent salmon-colored rash and systemic features such as hepatosplenomegaly, lymphadenopathy, leukocytosis, and elevations in inflammatory markers (ESR, CRP). Not all features of the disorder will be present at disease onset. It most often occurs in children aged younger than 5 years. This disorder is thought to represent an autoinflammatory disease, in which the innate immune system creates uncontrolled systemic inflammation. The development of macrophage activation syndrome can be fatal.
- Undifferentiated arthritis – Patients not meeting inclusion criteria for any disease or who meet more than 1 set of criteria are classified in this category.
M08.00 – Unspecified juvenile rheumatoid arthritis of unspecified site
410795001 – Juvenile rheumatoid arthritis
Differential Diagnosis & PitfallsBy definition, JIA has no known etiology. Therefore, other known causes of arthritis should be considered prior to diagnosing JIA.
- Psoriatic arthritis is included in classification criteria for JIA; see Synopsis.
- Septic arthritis – Fever, joint pain with erythema, and severely limited range of motion secondary to pain.
- Osteomyelitis – Usually affects children under the age of 5; associated with fever and pain, should be further evaluated with imaging.
- Lyme arthritis (see Lyme disease) – In endemic areas, it is a late manifestation of Lyme disease and usually presents with painless swelling of 1 knee.
- Systemic lupus erythematosus – Arthritis associated with other signs and symptoms of SLE.
- Malignancy – May present with an unusual pattern of joint involvement, systemic features, night-time pain, and low or inappropriately normal white blood cell and platelet counts despite the presence systemic inflammation.
- Trauma – Usually presents acutely.
- Acute rheumatic fever – Occurs 2-3 weeks after streptococcal infection. Children may develop a migratory polyarthritis, carditis, chorea, erythema marginatum, subcutaneous nodules, fever, elevated inflammatory markers, and heart block.
- Post-Streptococcus reactive arthritis – Occurs 1-2 weeks after a streptococcal infection; non-migratory arthritis; does not meet criteria for acute rheumatic fever.
- Reactive arthritis – Usually occurs several weeks after a genitourinary or gastrointestinal infection and primarily affects the lower extremities.
- Viral / post-viral arthritis – Parvovirus B19, rubella, hepatitis C virus, hepatitis B virus, or HIV.
- Transient synovitis – Usually follows viral upper respiratory tract infection; occurs in boys ages 3-10 and manifests with sudden-onset hip pain and limp. Children usually appear well and lack high fevers.
- Immunoglobulin A vasculitis (formerly Henoch-Schönlein purpura) – Palpable purpura in dependent areas, abdominal pain, renal disease.
- Kawasaki disease – Young children, aged 2 years, with conjunctivitis, cervical lymphadenopathy, erythema of the lips and oral mucosa, extremity changes, rash.
- Serum sickness – Rash, fever 1-2 weeks after offending drug.
- Cryopyrin‐associated periodic syndromes (CAPS)
Patient Information for Juvenile idiopathic arthritis in Child
OverviewJuvenile idiopathic arthritis (JIA) was once called juvenile rheumatoid arthritis or juvenile chronic arthritis. It is a group of several diseases of inflamed, stiff, or swollen joints (knees, ankles, hips, knuckles, etc.) in children age 16 and younger lasting for 6 weeks or more. Idiopathic means that the cause is uncertain or unknown. It can come on gradually or suddenly. Joint symptoms may occur in one or more joints.
Who’s At RiskChildren who have been on one or more courses of antibiotics may be at risk for developing JIA.
Signs & SymptomsThere are several different types of JIA, but all have joint swelling in common. Rash and sometimes spiking fever may occur together or off and on. The rash is usually not itchy, but it can be at times. The rash may last for a few hours.
Common joint symptoms include stiff, swollen, painful joints, usually in the knees, elbows, hips, ankles, and wrists. The fingers, feet, neck, and jaw may also be affected. A young child unable to report joint pain verbally may give other clues, such as stiffness in the morning, after naps, or after sitting for a period of time. Sometimes limping, loss of motion, or other changes in physical activity can be noticed.
Self-Care GuidelinesThe whole family will want to learn about JIA, how it affects your child and your family, and how you together can manage the illness and treatments. You can find information and parental support at American Juvenile Arthritis Organization, a council of the Arthritis Foundation.
When to Seek Medical CareIf you notice symptoms of JIA, such as swollen knees or wrists, rash, fever, or a limp, contact your child's pediatrician.
TreatmentsYour child's pediatrician may perform tests to rule out other conditions. The pediatrician may refer you to a pediatric rheumatology specialist or clinic, prescribe medications to control arthritis symptoms, and recommend physical therapy. You will also have the opportunity to learn about your child's condition, and how to maintain healthy joints to last them a lifetime.
Juvenile idiopathic arthritis in Child