A 3-year-old boy from rural India is brought to the clinic by his mother for assessment of growth. On examination, his height is below the 3rd percentile on the WHO growth chart, but his weight-for-height ratio is normal. Which is the most common cause of this anthropometric pattern?

Explanation

## Anthropometric Classification in Malnutrition **Key Point:** Height reflects long-term nutritional status and is the most sensitive indicator of chronic malnutrition. A child with low height but normal weight-for-height has **chronic protein-energy malnutrition (PEM)**, also called stunting. ### Anthropometric Patterns in PEM | Pattern | Height-for-Age | Weight-for-Height | Weight-for-Age | Type | Timeline | |---------|---|---|---|---|---| | **Chronic PEM (Stunting)** | ↓↓ | Normal | ↓ | Chronic malnutrition | Months to years | | **Acute PEM (Wasting)** | Normal | ↓↓ | ↓↓ | Acute malnutrition | Weeks to months | | **Marasmus** | ↓ | ↓↓ | ↓↓ | Severe acute PEM | Acute onset | | **Kwashiorkor** | Normal/↓ | ↓↓ | ↓↓ | Protein deficiency | Acute onset | **High-Yield:** In India, chronic PEM (stunting) is the most common form of malnutrition in children, affecting ~35–40% of children <5 years. It results from prolonged inadequate caloric and protein intake. ### Why This Pattern Indicates Chronic PEM 1. **Height reflects cumulative nutritional history** — it takes months to years to fall below the 3rd percentile. 2. **Normal weight-for-height** — indicates the child is not currently acutely malnourished; acute wasting would show low weight-for-height. 3. **Prevalence** — chronic PEM is far more common than endocrine causes (hypothyroidism, GH deficiency) in the Indian pediatric population. **Clinical Pearl:** Stunting is often irreversible after age 2–3 years, even with nutritional rehabilitation. Early intervention during the "critical window" (0–24 months) is essential for catch-up growth. [cite:Park 26e Ch 9]