Malnutrition Study Guide

📖 Core Concepts Malnutrition – any deficiency, excess, or imbalance of energy, protein, and nutrients that harms body tissues. Undernutrition – lack of nutrients → stunting, wasting, underweight. Overnutrition – excess nutrients → overweight, obesity, toxic micronutrient levels. Double Burden – coexistence of under‑ and over‑nutrition within the same population. Protein‑Energy Malnutrition (PEM) – simultaneous shortage of protein & energy; manifests as kwashiorkor (protein‑deficient, edema) or marasmus (energy‑deficient, severe wasting). Micronutrient Undernutrition – insufficient vitamins/minerals (e.g., iodine, vitamin A, iron). Exclusive Breastfeeding – infant receives only breast milk for the first 6 months; continues with complementary foods up to ≥2 years. Oral Rehydration Solution (ORS) – isotonic mix of water, glucose, and electrolytes that restores fluid & electrolyte balance in diarrheal illness. Severe Hypoglycemia Treatment – rapid 10 % glucose (or sucrose) bolus (50 mL) to raise blood glucose. Famine Scales (IPC, FEWS) – classify food‑security crises from “minimal” to “famine” using mortality, malnutrition, and market indicators. --- 📌 Must Remember Global burden (2017): 1 in 3 people affected by at least one form of malnutrition. Food insecurity 2023: 28.9 % of world population (2.33 billion) moderately/severely insecure. Child under‑nutrition: 148 million stunted, 45 million wasted, 45 % of child deaths linked to undernutrition. Vitamin A deficiency: 1/3 of under‑5 children; 670 000 deaths, up to 500 000 blindness cases. Iodine deficiency: 2 billion people (2017). Anemia (iron deficiency): 900 million women & children (2020). BMI thresholds: Overweight ≥ 25 kg/m²; Obesity ≥ 30 kg/m². WHO ORS recipe: 1 L water + 6 tsp (≈30 g) sugar + ½ tsp (≈2.5 g) salt → 75 mmol/L Na⁺ & glucose. Hypoglycemia bolus: 50 mL of 10 % glucose (10 g/100 mL) over 5–10 min; re‑check glucose at 15 min. Famine alert: Acute malnutrition > 30 % in under‑5s OR mortality > 2/10 000/day. --- 🔄 Key Processes Assessing Malnutrition (Children) Measure weight, height/length, MUAC. Plot on WHO growth chart → classify: Stunted: Height‑for‑age < ‑2 SD Wasted: Weight‑for‑height < ‑2 SD Underweight: Weight‑for‑age < ‑2 SD Preparing Standard ORS Mix 1 L safe water with 6 level teaspoons sugar & ½ tsp salt. Stir until dissolved; ensure solution is clear (no clumps). Managing Severe Hypoglycemia Verify low capillary glucose (< 2.5 mmol/L). Administer 50 mL 10 % glucose IV/IO over 5–10 min. Re‑measure glucose at 15 min; repeat if still low. Community Management of Severe Acute Malnutrition (SAM) Provide Ready‑to‑Use Therapeutic Food (RUTF) at home. Monitor weight gain weekly; treat infections with broad‑spectrum antibiotics. Using IPC Famine Scale Collect data on: acute malnutrition prevalence, crude mortality, market food price spikes. Assign Phase 1‑5; trigger appropriate humanitarian response. --- 🔍 Key Comparisons Kwashiorkor vs. Marasmus Kwashiorkor: Adequate calories, protein‑deficient → edema, low albumin, liver enlargement. Marasmus: Deficient calories and protein → severe wasting, minimal fat, normal albumin. Exclusive Breastfeeding vs. Formula Feeding EBF: Provides optimal nutrients, antibodies, reduces infection & mortality. Formula: Higher cost, risk of contamination, no maternal antibodies. Standard ORS vs. Reduced‑Osmolarity ORS Standard: 311 mOsm/L, higher Na⁺/glucose. Reduced‑Osmolarity (2003): 245 mOsm/L, lower Na⁺ (75 mmol/L) → less risk of hypernatremia. Undernutrition vs. Overnutrition Undernutrition: Stunting, wasting, micronutrient deficiency → weakened immunity, higher mortality. Overnutrition: Overweight/obesity → chronic NCDs (diabetes, CVD, cancers). --- ⚠️ Common Misunderstandings “All malnutrition = undernutrition.” → Overnutrition and micronutrient excess are also malnutrition. “Edema always means fluid overload.” → In kwashiorkor, edema reflects hypo‑albuminemia, not cardiac failure. “ORS cures diarrhea.” → ORS treats dehydration; it does not stop the diarrheal pathogen. “Breast milk is only needed for the first 3 months.” → WHO recommends exclusive breastfeeding for 6 months and continued up to ≥2 years. “High BMI always indicates overnutrition.” → Muscular individuals may have high BMI without excess fat; assess body composition. --- 🧠 Mental Models / Intuition “Energy‑Protein Balance Scale” – Imagine a see‑saw: too much energy (high‑calorie foods) tips toward overnutrition; too little protein/energy tips toward undernutrition. “The 3‑Stage Nutrition Triangle” – (1) Food Access → (2) Adequate Intake → (3) Utilization; a break at any stage creates malnutrition. “The Breastfeeding Shield” – Visualize breast milk as a shield that blocks infections, provides calories, and builds future cognitive reserve. --- 🚩 Exceptions & Edge Cases Micronutrient Toxicity: Excess vitamin A or iron can be harmful; supplementation must respect upper intake limits. Obesity in Low‑Income Settings: Even in food‑insecure populations, cheap energy‑dense foods can cause overnutrition. Acute vs. Chronic Malnutrition: Rapid weight loss (acute) needs immediate rehydration; chronic stunting requires long‑term nutrition and infection control. RUTF in Non‑SAM Cases: Supplementary feeding offers limited benefit for mildly undernourished children, especially in the poorest groups. --- 📍 When to Use Which RUTF vs. Hospital Care: Use RUTF for uncomplicated SAM (no medical complications); admit to hospital if edema, infection, or severe electrolyte imbalance. Standard ORS vs. Homemade ORS: Use commercial packets when available (accurate concentrations); homemade is acceptable in emergencies if prepared correctly. Reduced‑Osmolarity ORS: Preferred for all children with acute watery diarrhea (lower risk of hyponatremia). 10 % Glucose vs. 10 % Sucrose Bolus: Either works; glucose is faster‑acting, sucrose requires conversion to glucose. IPC Phase 3‑5 vs. Routine Monitoring: Activate IPC classification when acute malnutrition exceeds 15 % or mortality rises sharply. --- 👀 Patterns to Recognize Edema + Normal Weight‑for‑Height → Kwashiorkor. Severe Wasting + Low Serum Albumin → Marasmus. Rapid rise in local food prices + market speculation → Impending food‑security crisis (IPC Phase 2‑3). Children with recurrent infections + growth faltering → Underlying micronutrient deficiency (often vitamin A/iron). Diarrhea + continued breastfeeding → Better outcomes; formula or sugary drinks → Worsening dehydration. --- 🗂️ Exam Traps Trap: “All children with edema have overnutrition.” → Wrong; edema is classic for kwashiorkor (protein deficiency). Trap: “ORS should be given intravenously for severe dehydration.” → ORS is oral first; IV only when oral route impossible or severe shock. Trap: “BMI ≥ 25 kg/m² always indicates obesity.” → BMI ≥ 25 is overweight; obesity threshold is ≥ 30. Trap: “Micronutrient deficiency only occurs in low‑income countries.” → Hidden hunger (vitamin A, iron) can be prevalent even in middle‑income settings. Trap: “A 10 % glucose bolus is 100 mL of 10 % solution.” → Correct volume for severe hypoglycemia is 50 mL, not 100 mL. ---