Behaviour change

Behaviour change


  • Short lived change in behaviour (lethargy, mood disturbance, withdrawal, disinhibition) with clear cause and without other symptoms, signs or associated high risk conditions


  • Change in behaviour (less than four weeks) without clear cause and without other symptom(s), signs or associated high risk conditions


  • Pervasive change in behaviour (occurring in all environments) without clear cause, and;
    • One or more additional symptoms/signs that may occur with a brain tumour or;
    • Associated high risk conditions

Diagnostic pitfalls

Delayed diagnosis has been associated with:

  • Assuming that deterioration in academic performance at school/college is unrelated to a physical cause
  • Assuming that pervasive change in behaviour in adolescence is normal


  • Any child presenting with a pervasive change in behaviour requires a full physical, developmental and social assessment to look for possible underlying causes.
  • Ask specifically about associated symptoms and risk factors:
    • Personal or family history of a brain tumour
    • Leukaemia
    • Sarcoma and early onset breast or bowel cancer prior therapeutic CNS irritation
    • Neurofibromatosis types 1 and 2
    • Tuberous Sclerosis
    • Li Fraumeni Syndrome
    • Family history of colorectal polyposis
    • Gorlins Syndrome
    • Other familial genetic syndromes
  • Perform a HEADSSS assessment - a structured assessment of factors that can influence behaviour in young people
  • Pervasive behaviour change should be assessed with independent reports from teachers and other carers/professionals to seek evidence of its pervasive nature.
  • Plot growth in all children and pubertal status if applicable
  • Plot head circumference in children under two

Worrying features

  • Pervasive lethargy i.e. occurring in multiple environments (school, home, "fun" activities).
  • New onset mood disturbance/withdrawal/disinhibition