types of juvenile idiopathic arthritis

Last reviewed 01/2018

International League of Associations for Rheumatology (ILAR) has proposed the following criteria which classifies JIA into 7 heterogeneous subgroups

• oligoarticular
• no more than four affected joints in the first six months of disease
• 27–56% of JIA cases
• F>M
• often antinuclear antibody (ANA) positive. Strong association with anterior uveitis
• polyarticular – RF negative
• more than four affected joints in the first six months of disease; RF negative
• 11–28% of JIA cases
• F>M
• often symmetric involvement of small, medium and large joints
• polyarticular – RF positive
• more than four affected joints in the first six months of disease; RF positive on two separate occasions
• 2–7% of JIA cases
• F>M
• closely related to rheumatoid arthritis with similar phenotypic and prognostic features; classically affects adolescent girls
• enthesitis-related arthritis
• arthritis, enthesitis – tends to involve axial and weight-bearing joints including SIJ
• 3–11% of JIA cases
• M>F
• the juvenile spondyloparthropathy, often HLA-B27 positive males
• psoriatic arthritis
• arthritis, psoriasis
• 2–11% of JIA cases
• F>M
• also associated with dactylitis and nail changes such as pitting, ridging, onycholysis
• systemic onset
• fever, rash, arthritis (‘Still’s disease’); may have hepatosplenomegaly, lymphadenopathy
• 4–17% of JIA cases
• F>M
• can develop life-threatening immune dysregulation known as macrophage activation syndrome
• undifferentiated
• arthritis that does not meet criteria for other JIA subtypes
• 11–21% of JIA cases

Reference:

• (1) James RA, Wedderburn LR. Modern management of juvenile idiopathic arthritis. Prescriber. 2016; 27: 37–43