CSP Growth & Development in Pediatrics 2 — Questions and Answers
Question 1: A 9-month-old infant's weight is at the 5th percentile, length at the 50th percentile, and head circumference at the 50th percentile. Which pattern is most consistent with this presentation?
- Familial short stature
- Undernutrition with adequate linear growth (Correct answer)
- Constitutional growth delay
- Organic failure to thrive with normal neurodevelopment
Correct answer: Undernutrition with adequate linear growth
Weight lagging behind length and head circumference is the classic pattern of undernutrition (non-organic failure to thrive), as weight is the first parameter to falter when caloric intake is inadequate.
Question 2: Which of the following best describes the Fenton growth chart and its primary use?
- A chart for full-term infants from birth to 24 months
- A preterm-specific chart plotting growth from 22 weeks gestational age to 50 weeks PMA (Correct answer)
- A WHO chart adjusted for gestational age used after 40 weeks PMA
- A chart used exclusively for infants with intrauterine growth restriction
Correct answer: A preterm-specific chart plotting growth from 22 weeks gestational age to 50 weeks PMA
The Fenton 2013 growth chart is designed for preterm infants, covering 22 weeks gestational age through 50 weeks postmenstrual age, bridging neonatal and early postnatal growth assessment.
Question 3: At what age does the posterior fontanelle typically close in a healthy term infant?
- By 2 months of age (Correct answer)
- By 6 months of age
- By 12 months of age
- By 18 months of age
Correct answer: By 2 months of age
The posterior fontanelle closes by 6–8 weeks of age in most term infants, much earlier than the anterior fontanelle.
Question 4: A 3-year-old child's mid-parental height target is calculated at the 60th percentile. The child is currently at the 15th percentile for height. Which evaluation is most warranted?
- No evaluation needed; catch-up growth is expected until age 5
- Bone age radiograph and growth hormone evaluation (Correct answer)
- Thyroid function tests only
- Repeat measurement in 6 months to assess growth velocity
Correct answer: Bone age radiograph and growth hormone evaluation
A significant discrepancy between a child's current height percentile and the mid-parental target warrants investigation including bone age and endocrine evaluation to rule out growth hormone deficiency or other pathology.
Question 5: Which nutrient deficiency is most specifically associated with impaired linear growth even in the absence of overt malnutrition?
- Iron
- Vitamin A
- Zinc (Correct answer)
- Vitamin D
Correct answer: Zinc
Zinc deficiency specifically impairs linear growth and is associated with growth faltering even when overall caloric intake appears adequate, due to zinc's role in IGF-1 signaling and cell proliferation.
Question 6: During the adolescent growth spurt, girls typically achieve peak height velocity (PHV) at approximately what Tanner stage?
- Tanner stage 1
- Tanner stage 2
- Tanner stage 3–4 (Correct answer)
- Tanner stage 5
Correct answer: Tanner stage 3–4
Girls typically reach peak height velocity around Tanner stage 2–3 (early-to-mid puberty), earlier in pubertal development than boys who reach PHV at Tanner stage 3–4.
Question 7: A 6-month-old term infant was born at the 10th percentile for weight and is now at the 50th percentile. The parents are concerned about overfeeding. How should this trajectory be interpreted?
- The infant is at risk for obesity and feeding should be restricted
- This likely represents appropriate catch-up growth toward genetic potential (Correct answer)
- This pattern suggests growth hormone excess and warrants evaluation
- Weight crossing upward across percentiles after 4 months is always pathological
Correct answer: This likely represents appropriate catch-up growth toward genetic potential
Infants who were growth-restricted in utero or born small often demonstrate catch-up growth in the first 6–12 months as they track toward their genetic potential, which is a normal and expected pattern.
A 9-month-old infant's weight is at the 5th percentile, length at the 50th percentile, and head circumference at the 50th percentile.
Which pattern is most consistent with this presentation?