The phrase “three major types” can vary by source, but in practical clinical grouping, commonly discussed core categories include oligoarticular (few joints), polyarticular (many joints), and systemic-onset forms (with systemic features such as fever and rash). Oligoarticular disease involves fewer joints yet may require vigilant eye screening due to uveitis risk. Polyarticular disease affects more joints and often needs more intensive therapy and monitoring. Systemic-onset disease may feature fever spikes, rash, and broader inflammatory burden.

Subtype classification is not merely a label—it drives the monitoring protocol, complication risk profile, and treatment pathway. Because follow-up cadence and preventive screening differ across categories, the definitive subtype should be confirmed through pediatric rheumatology evaluation.