Short Stature

Short stature is height significantly below the expected range for age, sex, and genetic background. It is generally defined as height below the 3rd centile or more than two standard deviations below the population mean for age and sex. It is a common presenting concern in paediatric practice.

Careful, structured assessment centred on the growth pattern over time is essential. It distinguishes the substantial majority of presentations, which are normal variants (familial short stature and constitutional delay of growth and puberty), from the smaller but clinically important proportion with an underlying pathological cause needing targeted diagnosis and treatment.

Pathological causes to consider and exclude proactively include growth hormone deficiency, hypothyroidism, coeliac disease, Turner syndrome, and skeletal dysplasia.

Classification and pathophysiology

• Familial short stature reflects the individual's genetic potential based on parental height. It is the commonest explanation for short stature presenting for assessment.
  • Growth is proportionate and parallels the normal growth curve, rather than progressively falling away from it (termed growth faltering).
  • Height is consistent with the calculated mid-parental height target.
  • Pubertal timing is normal.
• Constitutional delay of growth and puberty is a normal variant with a slower tempo of growth and pubertal development.
  • Affected children typically have relatively short stature and delayed bone age during childhood and early adolescence.
  • A later, but normal, pubertal growth spurt follows. Final adult height is generally consistent with genetic potential.
  • A positive family history (a parent or sibling with a similar pattern of delayed growth and pubertal development) frequently supports the diagnosis.
• Pathological causes encompass a broad range of conditions.
  • Endocrine: growth hormone deficiency, hypothyroidism, and, in a chronically corticosteroid-treated child, iatrogenic Cushing syndrome.
  • Chronic systemic illness affecting growth: coeliac disease, inflammatory bowel disease, chronic kidney disease, and any other significant chronic childhood illness sufficient to impair growth.
  • Genetic and syndromic: Turner syndrome, a particularly important consideration in any girl with unexplained short stature.
  • Skeletal dysplasia: a group of genetic conditions producing disproportionate short stature, from a primary abnormality of bone and cartilage growth rather than any systemic hormonal or nutritional cause.
• The central distinguishing feature between benign normal variants and a pathological cause is the pattern of growth over time.
• A normal growth velocity (the rate of height gain over time) and a proportionate growth pattern parallel to the standard growth centile lines generally support a normal variant.
• A reduced growth velocity with progressive downward crossing of growth centiles is a significant warning sign. It warrants structured investigation for an underlying pathological cause.

• The essential foundation of assessment is the growth pattern over time. Plot serial height measurements on a standardised growth chart, ideally incorporating any available historical measurements, and calculate the mid-parental height target.
• A single, isolated height measurement provides substantially less diagnostic information than trend and growth velocity over time.
• A reduced growth velocity, with progressive downward crossing of growth centiles (rather than growth parallel to the child's established growth channel), is a significant warning sign warranting structured investigation. This applies regardless of absolute height at any single point in time.
• A child growing along a consistently low but stable centile is substantially less likely to have a significant pathological cause than a child with clear, progressive centile crossing, even if the latter's absolute height is less extreme.
• Additional features point to specific causes, each warranting targeted evaluation as clinically indicated:
  • disproportionate short stature (disproportionately short trunk or limbs relative to overall height) suggests skeletal dysplasia
  • dysmorphic features suggest Turner syndrome or another genetic syndrome
  • symptoms or signs of chronic systemic illness, including gastrointestinal symptoms suggesting coeliac disease or inflammatory bowel disease, or symptoms of hypothyroidism
• Take a family history, including parental heights (essential for calculating the mid-parental height target) and any family history of delayed puberty or a similar pattern of constitutional growth delay.
• Assess pubertal development, which helps distinguish constitutional delay of growth and puberty from other causes.

• Growth assessment is the essential, foundational approach. Plot serial height measurements against standardised growth charts, calculate growth velocity, and compare with the calculated mid-parental height target.
• Bone age assessment adds information on skeletal maturity. A bone age substantially delayed relative to chronological age supports constitutional delay of growth and puberty. A bone age broadly consistent with chronological age generally supports familial short stature.
• First-line screening for a child with a concerning growth pattern, particularly reduced growth velocity or significant, unexplained short stature, includes full blood count, inflammatory markers, coeliac serology, and thyroid function testing. These causes are relatively common and readily identifiable.
• In a girl, add karyotype analysis for Turner syndrome. Add renal and liver function assessment where clinically relevant to the broader presentation.
• Insulin-like growth factor 1 measurement supports assessment for suspected growth hormone deficiency. Where clinically indicated after initial assessment, add formal growth hormone stimulation testing. Normal growth hormone secretion is pulsatile, so a single, random growth hormone measurement has limited diagnostic value in isolation.
• Skeletal survey (full radiographic assessment of the skeleton) is indicated where clinical assessment suggests skeletal dysplasia from a pattern of disproportionate short stature. The radiographic pattern often gives characteristic diagnostic information for the particular dysplasia.
• Most short stature presentations are benign normal variants. Guide the intensity and extent of investigation by the overall clinical assessment, particularly growth velocity and pattern over time and any additional relevant feature. Do not pursue routine, full investigation in every child regardless of context.

• Familial short stature and constitutional delay of growth and puberty generally need no specific medical treatment.
• Management is reassurance about the expected, generally favourable natural history. Constitutional delay of growth and puberty achieves a final adult height consistent with genetic potential, albeit after a later pubertal growth spurt than typical peers.
• Continue growth monitoring to confirm the expected growth pattern continues as predicted.
• Where a specific pathological cause is identified, treat that condition. This covers coeliac disease, hypothyroidism, Turner syndrome, and the broader principles of chronic systemic illness management relevant to the condition identified. Treating the underlying cause is the primary, essential approach.
• Recombinant human growth hormone is an established, effective treatment for confirmed growth hormone deficiency. It has several other licensed indications, including Turner syndrome, chronic kidney disease-associated growth failure, and small for gestational age children without adequate catch-up growth.
• Growth hormone treatment needs regular, structured monitoring of growth response. Pay careful attention to safety considerations relevant to the underlying condition being treated.
• Significant, prolonged constitutional delay of growth and puberty causing substantial psychosocial distress may, in carefully selected cases and after individualised discussion, be managed with a short course of low-dose sex hormone therapy (testosterone in boys, or, less commonly, oestrogen in girls).
• This aims to accelerate the onset of puberty and its growth spurt without a significant, lasting effect on final adult height. It is reserved for cases where the psychosocial burden of delayed development is judged to warrant a time-limited intervention.
• Provide structured psychosocial support. Short stature can have a significant emotional and social impact, particularly in adolescence, when height differences relative to peers can become a source of significant distress.
• Arrange ongoing growth monitoring and follow up appropriate to the underlying cause and management approach.