Arthralgia/arthritis in children

Question 1

Probability diagnosis

Answer 1

Juvenile idiopathic arthritis (incl. still disease and psoriasis)

Viral polyarthritis (e.g. parvovirus, rubella)

Growing pains (leg)

Irritable hip (transient synovitis)

Traumatic arthritis

Reactive arthritis (post-infective)

Question 2

Serious disorders not to be missed

Answer 2

Vascular (haematological disorders):

• thalassaemia
• sickle cell anaemia
• haemophilia

Infection:

• rheumatic fever
• septic arthritis
• osteomyelitis
• meningococcaemia
• tuberculosis
• HIV

Cancer:

• leukaemia
• lymphoma
• neuroblastoma

Other:

• juvenile rheumatoid arthritis

Question 3

Pitfalls (often missed)

Answer 3

Hip disorders:

• Perthes disease
• slipped upper femoral epiphysis

Osteochondritis dissecans

Henoch-Schönlein purpura

Kawasaki syndrome

Rarities:

• scurvy
• rickets
• periodic fever syndrome

Question 4

Masquerades checklist

Answer 4

Drugs (e.g. penicillins, cotrimoxazole)

Spine: juvenile ankylosing spondylitis

Question 5

Key history and features in childhood

Answer 5

Arthralgia (joint pain) is a common problem in childhood.

The complaint demands respect because of the many serious problems causing it.

Arthritis may be part of an infectious disease such as rheumatic fever, rubella, varicella, human parvovirus, influenza or other viral infection and is seen with Henoch-Schönlein purpura.

Viral polyarthritis is very common in children.

FBC is helpful as it may show lymphopaenia, lymphocytosis or atypical lymphocytes.

Question 6

Diagnostic tips

Answer 6

Acute onset monoarticular arthritis associated with fever is septic until proved otherwise.

5% of children complain of recurrent limb pain, which often awakens them from their sleep.

A careful hx and exm are essential and perhaps simple basic investigations may be appropriate.

Growing pains and post-activity musculoskeletal pain are relatively common.