Multiple joint arthritis
Multiple swollen joints are unlikely to be due to infection (other than some forms of reactive arthritis) or trauma and make a systemic disease more likely.
Key conditions include:
- Juvenile Idiopathic Arthritis is likely but malignancy (leukaemia) has to be excluded.
- Metabolic conditions (osteomalacia / rickets).
- Chromosomal conditions (e.g., Downs syndrome associated arthritis).
- Inherited metabolic conditions (e.g., Mucopolysaccharidoses) and can occur with joint contractures.
- Multisystem disease such as Juvenile Systemic Lupus Erythematosus or Juvenile Dermatomyositis or Vasculitis tend to cause joint pain (arthralgia) rather than joint swelling.
- Rheumatic fever (a form of reactive arthritis that follows pharyngeal streptococcal infection) is uncommon in the UK, but common in developing countries. The arthritis can involve many joints, often flitting from joint to joint.
- Post viral arthritis such as with rubella infection can involve many joints whereas after chicken pox (varicella) may affect just one or several joints.
The photograph below shows polyarthritis affecting small joints of the hands and wrists (Juvenile Idiopathic Arthritis).
The photograph below shows swollen knees and quadriceps wasting due to chronic inflammatory arthritis.