Makindo Medical Notes

Related Subjects: |Causes of Short Stature in Children |Causes of Male Infertility |Causes of Tall Stature in Children |Marfan syndrome |Klinefelter Syndrome |Turner's syndrome (Children)

Definition

• Short stature is defined as a height more than two standard deviations below the mean for age, typically less than the 3rd percentile for age and gender. This indicates a height significantly lower than the average for the child’s age group.

Phases of Childhood Growth

• Infancy (Birth to 2-3 years): This is the fastest period of growth, primarily determined by nutrition and early feeding practices.
• Childhood (Age 2-3 to Puberty): Growth during this phase is influenced by hormones, notably growth hormone (GH), thyroid hormones (T3/T4), and insulin.
• Adolescent Growth (Onset of Puberty to Fusion of Epiphyses): Puberty triggers a growth spurt that is driven by GH and sex hormones (androgens in boys and estrogens in girls).
• Fusion of Epiphyses: This is a gradual process, influenced by estrogen from both male adrenal glands and female ovaries, which ultimately determines final adult height.

Causes of Short Stature

• Constitutional Growth Delay (~80%): Often observed when both parents are short, with normal growth velocity for age.
• Psychological Neglect or Stress: Environmental factors such as neglect or chronic stress can impact growth.
• Poverty and Physical Abuse: Nutritional deficiencies or trauma may lead to stunted growth.
• Drugs: Medications like steroids can impair growth.
• Genetic Conditions: Genetic disorders such as Turner syndrome or cystic fibrosis may result in growth delay.
• Ineffective Diet: Conditions like celiac disease can hinder nutrient absorption and stunt growth.
• Chronic Diseases: Inflammatory bowel disease and hypothyroidism can also lead to growth delays.
• Infection: Chronic infections (e.g., UTI, TB) may affect growth.
• Growth Hormone Deficiency: Insufficient GH production can severely limit growth.
• Rarer Conditions: Rare syndromes like Noonan syndrome may also cause short stature.

Growth Charts: Age (X axis) and Height (Y axis)

• Ensure you plot the child's age and height accurately on the growth chart to assess their growth trajectory.
• RCPCH Girls 0-4 years growth chart
• RCPCH Boys 0-4 years growth chart
• RCPCH Girls 2-18 years growth chart
• RCPCH Boys 2-18 years growth chart

Centiles

• Centile lines represent the range of expected weights and heights (or lengths). A centile indicates the percentage of children below that line:
• 50% of all children are below the 50th centile.
• 91% of all children are below the 91st centile.

Clinical Evaluation

• Initial evaluation of short and tall stature should involve a thorough history, physical examination, and accurate serial measurements, including determination of growth velocity, midparental height, and bone age.
• Dysmorphic features may suggest a genetic disorder.
• Midline defects may indicate abnormality in the growth hormone axis.
• Inspection, measurements, and physical examination techniques are essential in diagnosis.

Midparental Height Calculation

• For Girls: [Sum of both parents' heights (cm)] ÷ 2 - 7 cm.
• For Boys: [Sum of both parents' heights (cm)] ÷ 2 + 7 cm.
• This formula is not recommended if either parent has abnormal height.

Growth Velocity

• Birth to 12 months: Growth rate of 23 to 27 cm/year (9.06 to 10.63 inches).
• 12 months to 2 years: Growth rate of 10 to 14 cm/year (3.94 to 5.51 inches).
• 2 to 3 years: Growth rate of 8 cm/year (3.15 inches).
• 3 to 5 years: Growth rate of 7 cm/year (2.76 inches).
• 5 years to puberty: Growth rate of 5 to 6 cm/year (1.97 to 2.36 inches).
• Puberty (Girls): Growth rate of 8 to 12 cm/year (3.15 to 4.72 inches).
• Puberty (Boys): Growth rate of 10 to 14 cm/year (3.94 to 5.51 inches).

Bone Age

• Bone age should be compared with chronological age to narrow down the differential diagnosis of short stature.
• X-rays of the left wrist and hand are commonly used to assess bone age, with a database of norms for comparison.
• Children with normal growth variations may show advanced or delayed bone age, but a bone age more than two standard deviations from the mean is likely indicative of a pathological condition.

Common Causes of Short Stature

Investigations for Short Stature

• FBC, U&E, LFT, ESR, CRP
• Follicle-stimulating hormone, karyotyping (for Turner syndrome)
• Insulin-like growth factor 1 (for GH deficiency)
• Thyroid-stimulating hormone, free T4 (for hypothyroidism)
• Tissue transglutaminase and total immunoglobulin A (for celiac disease)
• Urinalysis (for renal disease)

References

• Evaluation of Short and Tall Stature in Children