According to WHO criteria, a child is classified as having severe acute malnutrition (SAM) when the weight-for-height Z-score falls below which value?

Explanation

## WHO Classification of Malnutrition in Children **Key Point:** The **WHO Z-score classification** uses standard deviations (SD) from the median to categorize the severity of malnutrition. **Severe Acute Malnutrition (SAM)** is defined as weight-for-height Z-score **< −3 SD** (or **< 70% of median weight-for-height**). ### WHO Malnutrition Grading by Z-Score | Z-Score Range | Classification | Clinical Significance | |---|---|---| | **−1 to 0 SD** | Normal | No malnutrition | | **−1 to −2 SD** | Mild Acute Malnutrition (MAM) | Increased infection risk | | **−2 to −3 SD** | Moderate Acute Malnutrition (MAM) | Requires nutritional intervention | | **< −3 SD** | **Severe Acute Malnutrition (SAM)** | **Requires urgent medical + nutritional care** | **High-Yield:** - **SAM** is a medical emergency with high mortality (10–30% if untreated). - SAM includes both **wasting** (low weight-for-height) and **stunting** (low height-for-age) if chronic. - The Z-score < −3 SD corresponds approximately to **<70% of expected weight-for-height**. ### Clinical Implications of SAM **Clinical Pearl:** Children with SAM present with: - Visible wasting (ribs, spine, hip bones prominent) - Loss of subcutaneous fat - Muscle atrophy - Increased susceptibility to infections (immunosuppression) - Metabolic complications (hypoglycemia, electrolyte imbalance) - Requires **inpatient nutritional rehabilitation** with close monitoring **Mnemonic: WASTING** — **W**eight loss, **A**trophic muscles, **S**kin folds prominent, **T**herapy-dependent (medical care), **I**nfection risk high, **N**utrition rehabilitation, **G**rowth recovery slow **Tip:** On NEET PG, always remember: **SAM = Z-score < −3 SD = medical emergency**. Questions often test this threshold. [cite:Park 26e Ch 10]