Managing Pediatric Growth Disorders

1. What is the child's age, sex, current height, and weight?
2. What are the serial height measurements over time (minimum 6-12 months of data)?
3. What is the birth length and birth weight? Was the child SGA?
4. What are the parents' heights (for mid-parental height calculation)?
5. What are the parents' pubertal timing histories (age of menarche for mother, growth spurt for father)?
6. Is there a family history of growth disorders, thyroid disease, or autoimmune conditions?
7. What is the child's Tanner stage (pubertal assessment)?
8. Does the child have chronic symptoms: fatigue, GI complaints, headaches, polyuria/polydipsia?
9. Is the child on any medications that might affect growth (corticosteroids, stimulants)?
10. Has a bone age X-ray been obtained?

Required Documents

• Serial height measurements plotted on WHO (< 2 years) or CDC (2-20 years) growth chart
• Birth records (length, weight, gestational age)
• Parental heights
• Bone age radiograph result (if obtained)
• Previous laboratory results (thyroid, IGF-1, celiac panel if done)
• Pubertal staging documentation

Step 1 — Growth Chart Analysis

When to Investigate

• Height < 3rd percentile (or < -2 SD) for age and sex
• Height significantly below mid-parental height target range
• Height velocity < 25th percentile for age (see velocity thresholds below)
• Crossing downward across 2 or more major percentile lines after age 2
• Height discordant with weight (weight preserved but height decelerating suggests endocrine cause)

Expected Height Velocity by Age

Height velocity < 4 cm/year in a prepubertal child aged 3+ years is abnormal and requires workup.

Mid-Parental Height (MPH) / Target Height

• Boys: (mother's height cm + father's height cm + 13) / 2
• Girls: (mother's height cm + father's height cm - 13) / 2
• Target range: MPH ± 8.5 cm (represents ~2 SD)
• If child's projected adult height (from bone age) falls outside target range, investigate

Step 2 — Bone Age Interpretation

Obtaining Bone Age

• Left hand and wrist AP radiograph (Greulich-Pyle atlas or Tanner-Whitehouse method)
• Indications: short stature evaluation, pubertal assessment, growth prediction

Interpretation Patterns

Predicted Adult Height

• Use Bayley-Pinneau tables with bone age to predict adult height
• Compare predicted adult height to mid-parental height target range
• If predicted height falls within MPH range → reassuring for normal variant
• If predicted height falls below MPH range → warrants further investigation

Step 3 — Differentiating Normal Variants from Pathology

Familial Short Stature (FSS)

• Parents short; child grows along a low percentile consistently
• Bone age = chronological age
• Puberty at normal time
• Adult height: short, but within MPH range
• Management: reassurance; no treatment indicated

Constitutional Delay of Growth and Puberty (CDGP)

• Family history of late puberty (mother's menarche > 14, father's growth spurt > 15)
• Child short for age but growing at normal velocity for bone age
• Bone age delayed 1-3 years; puberty delayed
• Adult height: usually normal (catches up during late adolescent growth spurt)
• Management: reassurance; consider short course of low-dose sex steroids at age 13-14 (boys) if psychosocial distress is significant

Red Flags for Pathologic Short Stature

• Height velocity < 4 cm/year (prepubertal)
• Height < -3 SD for age
• Disproportionate short stature (short limbs vs. trunk → skeletal dysplasia)
• Dysmorphic features
• Midline defects (cleft palate, single central incisor) → consider GH deficiency/pituitary abnormality
• Declining height percentile (crossing down) after age 2
• Weight gain with height deceleration (suggests hypothyroidism, Cushing syndrome)
• Absent or delayed puberty beyond 13 (girls) or 14 (boys)

Step 4 — Tiered Diagnostic Workup

Tier 1 — Initial Screen (For All Children With Concerning Growth)

Tier 2 — Directed by Clinical Clues

Tier 3 — Subspecialty Referral

• Pediatric endocrinology: GH stimulation testing, GH therapy initiation, precocious/delayed puberty management
• Genetics: dysmorphic features, skeletal dysplasia, suspected syndromic diagnosis
• Pediatric GI: suspected celiac disease not responding to diet, IBD, nutritional deficiency
• Pediatric nephrology: chronic kidney disease affecting growth

Step 5 — Growth Hormone Therapy Considerations

FDA-Approved Indications for GH Therapy in Children

• Growth hormone deficiency (GHD) — confirmed by stimulation testing
• Turner syndrome
• Chronic renal insufficiency (pre-transplant)
• Prader-Willi syndrome
• SGA without catch-up growth by age 2-4
• SHOX deficiency
• Idiopathic short stature (ISS): height < -2.25 SD (controversial; less insurance coverage)
• Noonan syndrome

GH Therapy Basics

• Dose: 0.024-0.034 mg/kg/day SC injection (varies by indication; higher for Turner, ISS)
• Monitoring: IGF-1 levels every 3-6 months (target age/sex-adjusted normal range; do not exceed +2 SD)
• Growth response: height velocity should increase in first year of treatment (first-year catch-up is the best predictor of long-term response)
• Side effects: injection site reactions, headache (pseudotumor cerebri — rare but check for papilledema), slipped capital femoral epiphysis, scoliosis progression, glucose intolerance

When to Stop GH Therapy

• Growth velocity < 2 cm/year
• Bone age closure (near adult height)
• Patient/family desire to discontinue
• Unacceptable side effects

Checkpoint B — Growth Disorder Management Review

• Serial height measurements plotted on appropriate growth chart (WHO or CDC)
• Height velocity calculated and compared to age norms
• Mid-parental height calculated and target range plotted
• Bone age obtained and interpreted
• Normal variants (FSS, CDGP) differentiated from pathologic growth failure
• Tier 1 labs obtained (CBC, CMP, TSH, celiac, IGF-1, IGFBP-3)
• Karyotype obtained for unexplained short stature in females
• Tier 2/3 workup directed by clinical findings
• Subspecialty referral placed if indicated (endocrine, genetics, GI)
• GH therapy criteria evaluated if GHD confirmed
• Pubertal staging documented at every growth visit
• All [VERIFY] flags resolved or escalated

Quality Audit

Guidelines

• Use WHO growth standards (birth to 2 years) and CDC growth reference charts (2-20 years) per AAP
• Follow Pediatric Endocrine Society guidelines for evaluation of short stature
• Bone age assessment: Greulich-Pyle atlas is the most widely used method; Tanner-Whitehouse for research precision
• GH stimulation testing: two failed stimulation tests required for GHD diagnosis (peak GH < 10 ng/mL on two separate tests)
• FDA-approved GH indications: GHD, Turner, CRI, PWS, SGA, SHOX deficiency, ISS, Noonan
• Turner syndrome: obtain karyotype in ALL girls with unexplained short stature (even without classic phenotypic features)
• Celiac disease: may present with isolated short stature and no GI symptoms — always screen
• Constitutional delay: bone age delay + family history of late puberty + normal growth velocity for bone age = reassurance; intervention only for significant psychosocial distress
• IGF-1 reference ranges are age- and Tanner-stage-specific; do not use adult ranges for children
• This skill produces clinical documentation; it does not replace clinical judgment