Outcomes in Juvenile Idiopathic Arthritis Save

Arthritis Research & Therapy reports on a prospective cohort of children with juvenile idiopathic arthritis (JIA) shows that the incidence has held steady at 12.8/100,000 children, but that the frequency uveitis and the need for orthopedic surgery has decreased in the last 20 years.

This Swedish cohort study enrolled JIA cases between 2002 and 2010. They identified 251 patients for the study.

The annual incidence rate for JIA was estimated to be 12.8/100,000 children < 16 years, with the highest age-specific annual incidence at the age of 2 years (36/100,000).

Oligoarthritis was the largest subgroup (44.7%), and systemic JIA was the smallest subgroup (2.8%). Also represented persistent oligoarthritis 33.5%, extended oligoarthritis 11.2%, undifferentiated JIA (16.3%), RF− polyarthritis (13.9%), enthesitis related arthritis (ERA -8.8%), RF+ polyarthritis (6.8%), juvenile psoriatic arthritis (6.8%).

Half of patients were ANA-positive, and of these, 60% had oligoarthritis. RF was seen in only 11%, with 63% of these having polyarticular JIA. HLA-B27 positivity was seen in 14.7%, with 49% of them have ERA. 

Methotrexate was the most frequently used DMARD 61%) and tumor necrosis factor alpha inhibitors were used in 24% of the children.

With a median follow-up time of 8 years, only 40% of the follow-up years were free of arthritis or uveitis.

Uveitis occurred in 11% of the children (8% were chronic uveitis), and the need for joint corrective orthopedic surgery was only 9.2%. Most surprising was the very low frequency of systemic JIA (Still's disease) at~3% (previously thought to occur in 10-20% of JIA cases).

Finding mMore than half the JIA patients with evidence of disease activity, suggests the need for vigilant follow-up and aggressive treatment.