The Child with Growth Problems

Question 1

Outline two rough rules for growth in children, one over the first fortnight of life and one over the first year

Answer 1

• Term babies - lose up to 10% birth weight in first week, regain by end of second
• Double weight by 4/12, triple by 12/12

Question 2

What is the definition of failure to thrive?

Answer 2

• Below 3rd percentile or dropping 2 or more percentile tracks

Question 3

What are the most common causes of failure to thrive?

Answer 3

• Non-organic (> 50% of cases)
  
  • Inadequate availability of food
  • Psychosocial deprivation
  • Neglect/child abuse

Question 4

Describe some organic causes of failure to thrive

Answer 4

• Decreased intake
  
  • Impaired suck/swallow - ENT malformation/neurological disorder
  • Anorexia related to chronic illness - Crohn’s, CF, CRF, CLD etc.
  • Inadequate retention
  • Vomiting
  • Severe GORD
• Inadequate absorption
  
  • Coeliac disease, CF, cow’s milk protein intolerance, short-gut syndrome, post-NE
  • Failure to utilise absorbed nutrients
  • Chromosomal disorders
  • IUGR or extreme prematurity
  • Metabolic disorders e.g. hypothyroidism, inborn errors of metabolism
• Increased requirements
  
  • Thyrotoxicosis
  • Chronic disease - CF, malignancy, infection (HIV), CHD, CLD, CRF

Question 5

How might you structure a failure to thrive history?

Answer 5

• Intake - detailed food history e.g. using a food diary
  
  • Number and volume of feeds
  • Breast milk supply, whether formula is correctly made up
  • Time taken to feed
  • Age solids commenced
  • Behaviour at mealtimes
• Output - amount and colour, dirty and wet nappies
• Relation to particular foods
• Birth history - prematurity, IUGR
• Child’s medical problems
• Family history of growth (parent and sibling heights) and disease
• Developmental
• Psychosocial problems at home

Question 6

Describe the formula for mid-parental height calculation

Answer 6

• Mid parental height (final height +/- 7-8cm)
  
  • Boys: (mother + 13 + father)/2
  • Girls: (mother - 13 + father)/2

Question 7

What are the most common causes of short stature? List some of the others

Answer 7

• Constitutional delay/familial delayed puberty
• Familial short stature
• Organic
  
  • IUGR
  • Skeletal: achondroplasia, radiation
  • Nutritional: malabsorptive disorder, rickets, PEM
  • Chronic illness
  • Iatrogenic: Cushing’s
  • Chromosomal: Prader-Willi, Silver-Russell, Turner, Down etc.
  • Endocrine: Hypothyroidism, GH deficiency, Cushing’s, pubertal delay/arrest
  • Psychosocial

Question 8

If someone has short stature that doesn’t appear to be familial, how might you investigate?

Answer 8

• Initial: bone age - if less than 25th percentile further tests indicated
• Consider: TFT, Hb, ESR, UEC/urine MCS, CMP, ALP, coeliac antibodies, karyotype
• Finally: GH studies

Question 9

What are the most common causes of early puberty?

Answer 9

• Gonadotrophin-dependent: related to activation of the HP-gonadal axis
  
  • Commonly: intracranial lesion e.g. hamartoma, radiation
  • LH>FSH
• Gonadotrophin-independent: related to excess sex steroids
  
  • CAH, adrenal/testicular/ovarian neoplasms, Mc-Cune Albright syndrome

Question 10

What is the earliest sign of true puberty?

Answer 10

Breast development/testicular enlargement

Question 11

What is the most common cause of delayed puberty? What are some others?

Answer 11

• Constitutional delay
• Low gonadotrophin secretion
  
  • Chronic disease, pituitary/hypothalamic disorder (think of intracranial lesion), acquired hypothyroidism, Kallmann syndrome (inability to smell), hyperprolactinaemia
• High gonadotrophin secretion (primary gonadal failure)
  
  • Chromosomal abnormalities (Klinefelter’s, Turner’s), hormone enzyme deficiency, acquired gonadal damage (surgery, chemotherapy, radiotherapy, trauma)