Severe malnutrition, also known as severe protein-energy malnutrition (PEM), is a devastating nutritional disorder characterized by a critical deficiency in energy and protein intake. It is not merely hunger, but a complex series of physiological and metabolic adaptations by the body to survive without adequate nutrients. In children, this condition is particularly dangerous and can lead to permanent damage if not treated promptly. The global health community defines severe acute malnutrition (SAM) by specific clinical indicators, including severe wasting and bilateral pitting oedema.
Types of severe malnutrition
Severe malnutrition is broadly classified into two main types, distinguished by their clinical presentation. Both are forms of severe protein-energy malnutrition but manifest differently depending on the primary nutrient deficit.
Marasmus: The wasting form
Marasmus is caused by a severe deficiency of all macronutrients: protein, carbohydrates, and fats. This leads to the body breaking down its own tissues for energy, resulting in severe weight loss and muscle wasting. Key characteristics include:
- Visible wasting of fat and muscle, giving an emaciated, shriveled appearance.
- Skin that is dry, loose, and hangs in folds.
- A gaunt, “old man” facial appearance in children due to the loss of facial fat.
- Bradycardia (slow heart rate) and hypotension (low blood pressure).
Kwashiorkor: The edematous form
Historically considered a protein-only deficiency, kwashiorkor is now understood to involve a combination of insufficient protein, key micronutrients, and increased oxidative stress. The defining feature is the presence of edema, or swelling, often masking the underlying malnutrition. Signs include:
- Bilateral pitting edema, typically in the feet, ankles, hands, and face.
- A bloated, distended abdomen due to fluid buildup (ascites) and an enlarged, fatty liver.
- Hair changes, such as brittleness, loss of pigment, and sparse texture.
- Skin lesions, depigmentation, and dermatitis.
- Lethargy and irritability.
Causes and risk factors
The roots of severe malnutrition are often complex and multi-faceted, ranging from socioeconomic factors to underlying health conditions.
- Food scarcity and poverty: Limited access to sufficient quantities of nutritious food is a primary driver, particularly in low- and middle-income countries and regions affected by conflict or disaster.
- Infectious diseases: Conditions like chronic diarrhea, measles, malaria, and HIV can trigger or worsen malnutrition. Frequent infections increase the body’s metabolic demands and impair nutrient absorption.
- Inadequate sanitation: Poor hygiene and unsafe water sources contribute to recurrent infections, perpetuating a vicious cycle of illness and undernutrition.
- Underlying medical conditions: Chronic illnesses such as cystic fibrosis, cancer, and chronic renal failure can interfere with nutrient absorption and increase metabolic needs.
- Inappropriate feeding practices: In infants, early weaning from breast milk without a nutritionally adequate replacement diet is a significant risk factor for kwashiorkor.
Diagnosis and clinical assessment
Diagnosis of severe malnutrition relies on a combination of physical examination, anthropometric measurements, and laboratory tests.
Diagnostic criteria for severe acute malnutrition (SAM)
The World Health Organization provides clear criteria for diagnosing SAM, especially in children aged 6 to 59 months:
- Weight-for-height Z-score (WHZ): A score below -3 standard deviations from the WHO Child Growth Standards median indicates severe wasting.
- Mid-upper arm circumference (MUAC): A measurement below 115mm is a diagnostic indicator.
- Bilateral pitting oedema: The presence of edema in both feet is a definitive clinical sign of kwashiorkor.
Other signs to assess
During an assessment, healthcare professionals also look for:
- Signs of infection.
- Hypoglycemia (low blood sugar) or hypothermia (low body temperature).
- Severe anemia, identified by severe palmar pallor.
- Clinical history of recent food intake, diarrhoea, or vomiting.
Treatment and management
Severe malnutrition is a medical emergency that requires careful and structured management to prevent life-threatening complications, such as refeeding syndrome. The standard approach, particularly for inpatient care, follows a two-phase process: stabilization and rehabilitation.
Stabilization phase (initial treatment)
This phase focuses on correcting life-threatening conditions. Key steps include:
- Treating hypoglycemia: Immediately providing a feed or 10% glucose solution.
- Treating hypothermia: Keeping the patient warm, often through skin-to-skin contact or using warm blankets.
- Correcting dehydration: Using a special oral rehydration solution (ReSoMal) designed for malnourished patients.
- Addressing electrolyte imbalances: Carefully replenishing potassium and magnesium over several weeks.
- Treating infections: Administering broad-spectrum antibiotics, as infections are common but signs like fever may be absent.
- Cautious feeding: Initiating small, frequent feeds with a low-protein formula (F-75) to prevent refeeding syndrome.
Rehabilitation phase (catch-up growth)
Once the patient is stable, the focus shifts to restoring weight and nutrients. Steps include:
- Achieving catch-up growth: Gradually increasing the energy and protein intake using a high-energy formula (F-100) or Ready-to-Use Therapeutic Food (RUTF).
- Correcting micronutrient deficiencies: Supplementing with vitamins and minerals, though iron is often withheld until weight gain begins to avoid exacerbating infections.
- Sensory stimulation and emotional support: Promoting development, especially in children.
- Follow-up: Providing ongoing support and monitoring after discharge.
Comparison of Marasmus and Kwashiorkor
| Feature | Marasmus (Wasting) | Kwashiorkor (Edematous) |
|---|---|---|
| Primary Deficiency | All macronutrients (protein, carbs, fats) | Predominantly protein, along with micronutrients |
| Key Clinical Sign | Severe muscle and fat wasting | Bilateral pitting edema |
| Appearance | Emaciated, shriveled skin, prominent bones | Bloated face, belly, and limbs; retained subcutaneous fat |
| Liver | Typically not enlarged | Enlarged, fatty liver is common |
| Metabolic Rate | Decreased to conserve energy | Significantly reduced due to metabolic dysfunction |
| Mood/Temperament | Often apathetic and irritable | Often irritable and apathetic |
| Recovery | Generally better prognosis if caught early | Often more dangerous due to multisystem involvement |
Conclusion
Severe malnutrition is a profound health crisis with devastating and lasting consequences, particularly for young children. By understanding what is severe malnutrition, recognizing its different forms like marasmus and kwashiorkor, and implementing rapid, carefully managed treatment plans, health outcomes can be significantly improved. The structured medical management, from stabilization to rehabilitation, is crucial for survival and recovery. Beyond clinical care, effective prevention strategies, including addressing food insecurity, promoting healthy feeding practices, and controlling infectious diseases, are essential for breaking the cycle of malnutrition and building a healthier future for the most vulnerable populations.
For more detailed information on inpatient management protocols, you can consult guidelines from authoritative sources such as the National Institutes of Health.
