What is the workup for a child with short stature (below 5% of height)?

Comprehensive Workup for a Child with Short Stature

The workup for a child with short stature (below 5% of height) should begin with regular height measurements, assessment of growth velocity, calculation of genetic target height, and evaluation of bone age, followed by targeted laboratory testing to identify underlying pathologies. 1

Initial Assessment

• Height (or supine length for children under 2 years) should be measured by trained personnel using calibrated equipment and compared with age-specific and sex-specific reference charts 1
• Calculate height velocity over a minimum period of 6 months to identify reduced growth rates (below 25th percentile) or catch-up growth (above 75th percentile) 1
• Assess growth potential through calculation of genetic target height based on parental heights and evaluation of bone age through radiography of the left wrist 1
• Review previous growth measurements to identify crossing of centile lines between ages 3-adolescence, which suggests pathology 1
• Determine if short stature is proportionate or disproportionate through careful physical examination and measurements 1

Differentiating Normal Variants from Pathologic Causes

• Evaluate for constitutional delay of growth (characterized by deceleration of height in first 3 years, normal childhood velocity of 4-7 cm/year, delayed bone age and puberty) 1
• Assess for familial short stature (early deceleration in growth, normal velocity, normal bone age, height appropriate for target height) 1
• Consider idiopathic short stature when no other cause is identified 2

Laboratory Evaluation

Before considering growth hormone therapy, the following assessments should be performed 1:

• Serum creatinine and estimated glomerular filtration rate
• Blood urea nitrogen, calcium, phosphorus, alkaline phosphatase
• Bicarbonate, parathyroid hormone, 25(OH) vitamin D levels
• Serum albumin, fasting glucose, and glycosylated hemoglobin
• Thyroid function tests (TSH and free T3)
• Insulin-like growth factor 1 concentrations
• Chromosomal analysis in girls to evaluate for Turner syndrome 1

Imaging Studies

• Radiography of the left wrist for bone age determination 1
• Skeletal survey if disproportionate short stature is present to evaluate for skeletal dysplasia 1
• Consider skeletal survey even in cases of familial short stature to look for subtle changes that might be diagnostic, especially if height is more than 3 standard deviations below mean 1
• Fundoscopic examination 1

Genetic Testing Considerations

• Chromosome analysis should be performed if physical examination does not suggest a recognizable syndrome 1
• Consider SHOX gene testing if clinical or radiographic findings suggest dyschondrosteosis 1
• If chromosome analysis is negative, genomic array studies may be considered to evaluate for changes in genome copy number 1

Special Considerations

• For children with intrauterine onset of short stature, compare birth weight, length, and head circumference to identify patterns 1
• Evaluate for endocrinopathies, particularly growth hormone deficiency, which is diagnosed in approximately 18.7% of children with short stature 3
• In children with significant short stature (below -3 standard deviations), immediate workup is indicated as they are more likely to have underlying pathology 4, 2
• Assess for chronic diseases that may affect growth, including celiac disease, inflammatory bowel disease, and chronic kidney disease 5, 1

Follow-up Recommendations

• If no diagnosis is apparent after initial evaluation, periodic reassessment is indicated 1
• The timing of reassessment depends on the child's age, presence of other developmental or physical features, family interest, and changes in family history 1
• For children with height SDS between -2 and -3, regular follow-up is recommended, while those below -3 require immediate comprehensive evaluation 4