Kwashiorkor
Overview
Plain-Language Overview
Kwashiorkor is a form of severe malnutrition that primarily affects children who have an inadequate intake of protein despite consuming enough calories. It often occurs in regions where food scarcity or famine is common. Children with Kwashiorkor may appear swollen due to fluid retention and have a distended belly. Other symptoms include irritability, an enlarged liver, and thinning hair. This condition can lead to serious health problems if not treated promptly.
Clinical Definition
Kwashiorkor is a severe form of protein-energy malnutrition characterized by adequate caloric intake but insufficient protein consumption, leading to hypoalbuminemia and subsequent edema. It predominantly affects young children in developing countries during weaning when dietary protein is inadequate. The pathophysiology involves decreased plasma oncotic pressure causing fluid to accumulate in the interstitial space, resulting in peripheral and abdominal edema. Clinical features include a distended abdomen, hepatomegaly due to fatty liver infiltration, skin changes such as hyperpigmentation and desquamation, and hair abnormalities including depigmentation and thinning. Patients often present with irritability and lethargy. Laboratory findings typically show low serum albumin, anemia, and electrolyte imbalances. Kwashiorkor differs from marasmus, which is characterized by overall calorie deficiency without edema. The condition requires prompt nutritional rehabilitation to prevent morbidity and mortality.
Inciting Event
- Sudden transition from breastfeeding to a diet low in protein but high in carbohydrates.
- Episodes of acute infections that increase metabolic demands.
- Periods of famine or food shortage.
Latency Period
- none
Diagnostic Delay
- Misattribution of edema and abdominal distension to other causes such as infections or liver disease.
- Lack of awareness of protein malnutrition signs in early stages.
- Limited access to healthcare in affected regions.
Clinical Presentation
Signs & Symptoms
- Generalized edema causing swelling of limbs and face.
- Irritability and lethargy due to malnutrition.
- Anorexia and poor appetite.
- Diarrhea and increased susceptibility to infections.
- Delayed growth and developmental milestones.
History of Present Illness
- Progressive edema, especially in the lower extremities and face.
- Abdominal distension due to ascites and hepatomegaly.
- Irritability and lethargy.
- Poor appetite and failure to thrive.
- Skin changes such as hyperpigmentation and 'flaky paint' dermatosis.
Past Medical History
- History of inadequate dietary protein intake.
- Previous episodes of infections such as diarrhea or respiratory illness.
- Recent weaning from breast milk.
Family History
- none
Physical Exam Findings
- Presence of edema, especially in the lower extremities and face.
- Enlarged liver (hepatomegaly) due to fatty infiltration.
- Dry, thin, and peeling skin with areas of hyperpigmentation or hypopigmentation.
- Thinning, brittle, and depigmented hair often described as 'flag sign'.
- Muscle wasting with relative preservation of subcutaneous fat.
Diagnostic Workup
Diagnostic Criteria
Diagnosis of Kwashiorkor is based on clinical evidence of severe protein malnutrition with characteristic peripheral edema, hypoalbuminemia, and a history of inadequate protein intake despite sufficient caloric consumption. Key diagnostic features include bilateral pitting edema, a distended abdomen, hepatomegaly, and skin or hair changes such as hyperpigmentation or depigmentation. Laboratory tests typically reveal low serum albumin levels and may show anemia or electrolyte disturbances. Differentiation from marasmus is essential, as marasmus lacks edema and involves overall calorie deficiency.
Pathophysiology
Key Mechanisms
- Kwashiorkor results from severe protein deficiency despite adequate caloric intake, leading to hypoalbuminemia and subsequent edema.
- The lack of protein impairs synthesis of essential plasma proteins, causing decreased oncotic pressure and fluid leakage into interstitial spaces.
- Oxidative stress and impaired antioxidant defenses contribute to cellular damage and clinical manifestations.
- Impaired immune function due to protein malnutrition increases susceptibility to infections.
| Involvement | Details |
|---|---|
| Organs | Liver: Central organ affected with fatty change and decreased protein synthesis. |
| Kidneys: May be affected by electrolyte imbalances and dehydration. | |
| Gastrointestinal tract: Impaired absorption and increased risk of infections. | |
| Tissues | Muscle tissue: Shows wasting due to protein catabolism. |
| Adipose tissue: May be depleted but less so than muscle in Kwashiorkor. | |
| Liver tissue: Exhibits fatty infiltration and impaired function. | |
| Cells | Hepatocytes: Liver cells that show fatty change due to impaired protein synthesis in Kwashiorkor. |
| Adipocytes: Fat cells that may be relatively preserved despite overall malnutrition. | |
| Immune cells: Reduced function and number contribute to increased susceptibility to infections. | |
| Chemical Mediators | Albumin: Low serum levels cause decreased oncotic pressure leading to edema. |
| C-reactive protein (CRP): Elevated in response to inflammation and infection. | |
| Cytokines: Increased pro-inflammatory cytokines contribute to metabolic disturbances. |
Treatment
Pharmacological Treatments
Multivitamin supplements
- Mechanism: Replenish essential vitamins and minerals deficient in malnutrition
- Side effects: Rare allergic reactions
Antibiotics
- Mechanism: Treat secondary infections common in malnourished patients
- Side effects: Gastrointestinal upset, allergic reactions
Electrolyte replacement
- Mechanism: Correct electrolyte imbalances such as hypokalemia and hypomagnesemia
- Side effects: Hyperkalemia if overdosed
Non-pharmacological Treatments
- Provide gradual nutritional rehabilitation with a high-protein, energy-dense diet to restore body protein stores.
- Ensure adequate hydration with oral rehydration solutions to prevent dehydration.
- Monitor and treat any underlying infections or complications promptly.
- Educate caregivers on proper infant feeding practices to prevent recurrence.
Prevention
Pharmacological Prevention
- Supplementation with multivitamins including vitamin A and zinc.
- Use of iron supplements to prevent anemia in at-risk populations.
Non-pharmacological Prevention
- Ensuring adequate protein and calorie intake in infants and children.
- Promoting exclusive breastfeeding for the first 6 months of life.
- Improving food security and access to nutritious foods.
- Education on proper weaning and complementary feeding practices.
- Improving sanitation and reducing exposure to infections.
Outcome & Complications
Complications
- Sepsis due to impaired immune function.
- Hypoglycemia from inadequate nutritional intake.
- Electrolyte imbalances leading to cardiac arrhythmias.
- Hepatic failure from fatty liver infiltration.
- Skin infections and ulcerations.
| Short-term Sequelae | Long-term Sequelae |
|---|---|
|
|
Differential Diagnoses
Kwashiorkor versus Marasmus
| Kwashiorkor | Marasmus |
|---|---|
| Pitting edema due to hypoalbuminemia is a hallmark of Kwashiorkor | Severe wasting with loss of muscle and fat but without significant edema |
| Serum albumin is markedly decreased in Kwashiorkor | Serum albumin levels are usually normal or only mildly decreased |
| Skin changes such as flaky paint dermatosis and hair depigmentation are characteristic | Skin changes such as hyperpigmentation or dermatosis are absent |
Kwashiorkor versus Nephrotic Syndrome
| Kwashiorkor | Nephrotic Syndrome |
|---|---|
| Edema in Kwashiorkor is due to hypoalbuminemia from protein malnutrition, not renal loss | Massive proteinuria (>3.5 g/day) is a defining laboratory feature |
| Fatty liver and skin/hair changes are characteristic of Kwashiorkor | Hyperlipidemia and lipiduria are common laboratory abnormalities |
| Serum albumin is low due to inadequate intake rather than renal loss | Edema is often periorbital and generalized but without malnutrition signs |
Kwashiorkor versus Vitamin B6 (Pyridoxine) Deficiency
| Kwashiorkor | Vitamin B6 (Pyridoxine) Deficiency |
|---|---|
| Edema and hepatomegaly due to fatty liver are typical in Kwashiorkor | Peripheral neuropathy and seizures are common neurological features |
| Flaky paint dermatosis and hair changes are distinctive skin findings | Cheilitis and glossitis are prominent mucocutaneous signs |
| Serum albumin is significantly decreased in Kwashiorkor | Serum pyridoxal phosphate levels are low |