Key clinical features to consider when diagnosing Juvenile Idiopathic Arthritis (JIA) in a child include:
- Persistent joint swelling, redness, or stiffness, especially if the limp or joint symptoms are worse in the morning, indicating inflammatory joint disease.
- Limping or refusal to bear weight on the affected limb, often accompanied by painful limitation of joint movement.
- Joint pain and stiffness lasting for at least 6 weeks, which is a hallmark of JIA and helps differentiate it from transient causes of limp.
- Systemic features such as low-grade fever, fatigue, weight loss, or unexplained rash may be present, reflecting systemic inflammation.
- Absence of acute infection signs (e.g., high fever, severe pain waking the child at night) helps distinguish JIA from septic arthritis or malignancy, though specialist assessment is essential to exclude these.
- Multiple joint involvement or involvement of small joints can be a feature, but JIA may also present with monoarthritis.
- Symptoms persisting beyond transient synovitis duration, especially in children older than 3 years, as transient synovitis is rare under this age and septic arthritis is more common.
These clinical features should prompt urgent referral to a paediatric rheumatologist or appropriate specialist for further assessment and diagnosis, as early intervention improves outcomes NICE CKS. Imaging such as ultrasound or MRI may assist in detecting synovitis and joint damage but is not routinely used in primary care [Dimitriou et al., 2017].
In summary, the diagnosis of JIA relies on identifying persistent inflammatory joint symptoms (swelling, stiffness, pain), systemic signs of inflammation, and excluding other serious causes of limp such as infection, malignancy, or trauma NICE CKS. Recent literature supports the use of advanced imaging and highlights the heterogeneity of JIA presentations, reinforcing the need for specialist evaluation Dimitriou et al. 2017.
Key References
- CKS - Childhood limp - acute
- CKS - Limp (childhood) - acute
- CKS - Acute childhood limp
- CKS - Rheumatoid arthritis
- NG143 - Fever in under 5s: assessment and initial management
- NG100 - Rheumatoid arthritis in adults: management
- (Dimitriou et al., 2017): Imaging of Juvenile Idiopathic Arthritis.
- (Ruperto et al., 2021): Tofacitinib in juvenile idiopathic arthritis: a double-blind, placebo-controlled, withdrawal phase 3 randomised trial.
- (Papadopoulou et al., 2023): Juvenile idiopathic inflammatory myositis: an update on pathophysiology and clinical care.