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Marasmus and Kwashiorkor
Both are forms of Severe Acute Malnutrition (SAM), collectively called Protein-Energy Malnutrition (PEM). They differ primarily in the relative deficit of protein versus total calories.
FIG. 7.17 - (A) Marasmus: loss of muscle mass and subcutaneous fat; head appears too large for the emaciated body. (B) Kwashiorkor: generalized edema seen as ascites and puffiness of face, hands, and legs.
Marasmus
Definition & Cause
Marasmus results from a severe deficiency of total calories (both protein and energy). Weight falls to <60% of expected for sex, height, and age.
Pathophysiology
- The body catabolizes the somatic protein compartment (muscle) to provide amino acids as fuel - this is an adaptive response.
- The visceral protein compartment is relatively spared, so serum albumin is normal or near-normal.
- Subcutaneous fat is mobilized and consumed as fuel.
- Low leptin stimulates the hypothalamic-pituitary-adrenal axis → elevated cortisol → contributes to lipolysis.
Clinical Features
| Feature | Finding |
|---|
| Weight | <60% of expected |
| Edema | Absent |
| Muscle/fat | Severely wasted |
| Serum albumin | Normal or mildly reduced |
| Appetite | Good (alert, hungry) |
| Mood | Alert |
| Subcutaneous fat | Markedly depleted |
| Liver | Not enlarged |
- Extremities are emaciated; the head appears disproportionately large
- Anemia and multivitamin deficiency signs are present
- T cell-mediated immune deficiency → concurrent infections are common
Kwashiorkor
Definition & Cause
Kwashiorkor occurs when protein deprivation is relatively greater than caloric deficit. The name comes from the Ga language of Ghana, meaning "disease of the displaced child" - the child displaced from the breast when another baby is born, subsequently fed an almost exclusively carbohydrate diet.
Common settings:
- Early weaning in impoverished regions (sub-Saharan Africa, Southeast Asia, Central America)
- Chronic diarrheal states (malabsorption)
- Protein-losing enteropathy, nephrotic syndrome, extensive burns
- Rare: fad diets, rice-based beverage substitution for milk (reported in the US)
Pathophysiology
- Marked protein deprivation → severe loss of the visceral protein compartment
- Hypoalbuminemia → generalized/dependent edema (hallmark)
- Reduced synthesis of apoprotein (carrier protein for lipoproteins) → fatty liver (hepatomegaly)
- Leaky cell membranes allow potassium and intracellular ions to leak into the extracellular space → osmotic water movement → edema
- Often triggered or worsened by a superimposed infection/physiologic stress on a baseline malnourished child
Clinical Features
| Feature | Finding |
|---|
| Weight | 60-80% of expected (masked by edema) |
| Edema | Present (generalized/dependent) - the cardinal sign |
| Muscle/fat | Relatively spared |
| Serum albumin | Low (hypoalbuminemia) |
| Appetite | Poor |
| Mood | Apathetic alone; irritable when handled |
| Liver | Enlarged, fatty |
| Abdomen | Protuberant (weak muscles + hepatomegaly + intestinal distention; ascites rare) |
Characteristic skin & hair changes:
- Skin: alternating zones of hyperpigmentation, desquamation, and hypopigmentation - the "flaky paint" or "crazy paving" appearance
- Hair: loss of color, alternating light/dark bands ("flag sign"), straightening, fine texture, easily plucked ("easily removable")
Side-by-Side Comparison
| Feature | Marasmus | Kwashiorkor |
|---|
| Primary deficit | Total calories (protein + energy) | Protein > energy |
| Weight | <60% expected | 60-80% expected |
| Edema | Absent | Present (cardinal) |
| Serum albumin | Normal/near-normal | Low |
| Subcutaneous fat | Markedly depleted | Relatively spared |
| Muscle wasting | Severe | Mild (masked by edema) |
| Liver | Normal | Fatty (enlarged) |
| Appetite | Good | Poor |
| Mood | Alert | Apathetic/irritable |
| Skin/hair changes | Absent | "Flaky paint," flag sign |
| Immune deficiency | T-cell mediated | Present + worse |
Marasmic-Kwashiorkor
A mixed form exists - features of both conditions - seen when marasmus is complicated by superimposed severe protein deficiency or infection.
Assessment Tools
- Growth charts: weight-for-age is the first indicator of PEM
- Mid-upper arm circumference (MUAC):
-
13.5 cm = normal
- 12.5-13.5 cm = mild-moderate malnutrition
- <12.5 cm = severe malnutrition (MUAC is unreliable under 1 year; stable 1-5 years)
- Waterlow Classification:
- Wasting = weight for height (acute malnutrition)
- Stunting = height for age (chronic malnutrition)
- Severe = weight-for-height <70% of median OR >-3 Z-score
Management
Principles (WHO 10-step approach for SAM)
- Treat/prevent hypoglycemia
- Treat/prevent hypothermia
- Treat/prevent dehydration (use ReSoMal, not standard ORS - lower sodium, higher potassium)
- Correct electrolyte imbalance (especially potassium and magnesium)
- Treat/prevent infection (broad-spectrum antibiotics empirically)
- Correct micronutrient deficiencies (vitamin A, folic acid, zinc, copper, multivitamins - no iron initially)
- Cautious initial feeding (stabilization phase)
- Rebuild wasted tissues (rehabilitation phase - high-protein, high-calorie feeds)
- Provide stimulation, play, and emotional support
- Prepare for follow-up after recovery
Refeeding syndrome is a risk - start low, go slow with calories.
Prevention
- Promote breastfeeding
- Develop low-cost weaning foods; frequent small feeds
- Immunization programs (infections worsen nutritional status)
- Nutrition education and family diet improvement
- Family planning (birth spacing)
- Food fortification
Sources: Robbins & Kumar Basic Pathology; Robbins, Cotran & Kumar Pathologic Basis of Disease; Sleisenger and Fordtran's Gastrointestinal and Liver Disease; Park's Textbook of Preventive and Social Medicine