Multiple swollen joints
Multiple swollen joints are unlikely to be due to infection (other than some forms of reactive arthritis) or trauma and makes a systemic disease more likely.
Key conditions include:
- Juvenile Idiopathic Arthritis is likely but malignancy (leukaemia) has to be excluded. Other forms of chronic inflammatory arthritis include Lyme disease.
- Metabolic conditions (osteomalacia / rickets).
- Chromosomal conditions (e.g., Downs syndrome associated arthritis).
- Inherited metabolic conditions (e.g., Mucopolysaccharidoses).
- Multisystem disease such as Juvenile Systemic Lupus Erythematosus or Juvenile Dermatomyositis or Vasculitis tend to cause joint pain (arthralgia) rather than joint swelling. Henoch Schonlein Purpura presents with vasculitic arthritis, arthritis and arthralgia: renal and gut involvement can also occur.
- Rheumatic fever (a form of reactive arthritis that follows pharyngeal streptococcal infection) is uncommon in the UK and North America, but remains a common and serious disease in many countries such as New Zealand and Australia, (particularly indigenous populations), India and South East Asia. The arthritis tends to involve many joints, often migratory from joint to joint, but can present with a monoarthritis.
- Post viral arthritis (e.g., with rubella, parvo virus or arbovirus infection) can involve many joints and sometimes with multisystem features. Chicken pox (varicella) can lead to an oligo-arthritis or polyarthritis.
- Skeletal dysplasia: can be suspected with short stature, joint swelling (due to bone deformity), disability and pain. There may be extra-articular features (e.g., short stature, dysmorphism) and there may be a positive family history.
- Poncet's disease is a form of reactive arthritis as a hypersensitivity response to Tuberculosis. It often presents with fever, weight loss and symmetrical polyarthritis.
The photograph below shows polyarthritis affecting small joints of the hands and wrists in polyarticular Juvenile Idiopathic Arthritis