From the Guidelines
Rheumatoid arthritis, specifically Juvenile Idiopathic Arthritis (JIA), is rare in 9-year-old boys, affecting approximately 1 in 1,000 children. The prevalence of JIA is estimated to be around 1 per 1,000 children, as stated in the 2019 American College of Rheumatology guideline 1. In a child this age, the most likely form would be polyarticular JIA, which affects multiple joints.
Common Comorbidities
Some common comorbidities associated with JIA include:
- Uveitis (eye inflammation)
- Growth disturbances
- Psychological impacts like depression or anxiety These comorbidities can significantly impact the quality of life and morbidity of the child, highlighting the importance of prompt diagnosis and treatment.
Causes of JIA
The causes of JIA are not fully understood but involve a combination of genetic predisposition and environmental triggers that lead to immune system dysregulation, as mentioned in the 2019 guideline 1. There is no single cause, though certain genetic markers increase susceptibility. Infections may trigger the onset in genetically predisposed children.
Management
Management typically involves a multidisciplinary approach with pediatric rheumatologists, including medications such as:
- NSAIDs (like naproxen or ibuprofen)
- Disease-modifying antirheumatic drugs (DMARDs) like methotrexate
- In more severe cases, biologic agents like etanercept or adalimumab Early diagnosis and treatment are crucial to prevent joint damage and growth complications, so any persistent joint pain, swelling, or stiffness in a child should prompt medical evaluation, as emphasized in the guideline 1.
From the Research
Prevalence of Rheumatoid Arthritis in Children
- Rheumatoid arthritis in children is referred to as Juvenile Idiopathic Arthritis (JIA) 2
- JIA is the most common chronic inflammatory rheumatic condition of childhood 2
- It is an umbrella term for arthritis of unknown origin, lasting for >6 weeks with onset before 16 years of age 2
Comorbidities and Causes
- The pathogenesis of JIA involves autoimmune and autoinflammatory mechanisms, similar to arthritis observed in adults 2
- There are seven mutually exclusive categories of JIA based on disease manifestations during the first 6 months of disease, according to the International League Against Rheumatism (ILAR) classification 2
- JIA can influence all aspects of a child's and their family's life, and improvement of health-related quality of life is a key treatment goal 2
Specifics to a 9-year-old Boy
- Approximately 10% of JIA patients have end-stage degenerative changes requiring total hip arthroplasties (THAs) and total knee arthroplasties (TKAs) 3
- The goal of drug therapy in JIA is to rapidly reduce disease activity to inactive disease or clinical remission, minimize drug side effects, and achieve a quality of life comparable to that of healthy peers 2
- Note that study 4 is not relevant to the topic of rheumatoid arthritis in children.