Kwashiorkor

Kwashiorkor is the oedematous form of severe acute malnutrition, characterised by bilateral pitting oedema with skin and hair changes, and often a fatty liver. It occurs when energy and protein intake is inadequate and is usually precipitated by infection.

It is most common in children aged 6 months to 3 years in settings of food insecurity, especially around weaning, after measles, diarrhoea or HIV infection. Bilateral pitting oedema of any grade defines severe acute malnutrition irrespective of weight, and carries a higher mortality than non-oedematous disease.

Pathophysiology.

The cause is not fully explained by protein deficiency alone. Contributing factors include oxidative stress with low antioxidant reserves, altered gut microbiota, aflatoxin exposure, infection and reduced capacity to handle free radicals.

Hypoalbuminaemia, increased capillary permeability, sodium retention and low cardiac output produce oedema. Fatty liver results from impaired lipoprotein synthesis. The gut mucosa is atrophic, with malabsorption and bacterial translocation.

• Bilateral pitting oedema starting in the feet and legs and spreading to the hands, face and trunk. The child may appear deceptively well nourished.
• Skin: hyperpigmented patches that peel, leaving raw hypopigmented areas (flaky paint dermatosis), and fissures in the skin folds.
• Hair: thin, sparse, straight and depigmented, with a flag sign of alternate dark and pale bands.
• Apathy, irritability and misery, anorexia, hepatomegaly, diarrhoea, hypothermia, and signs of vitamin A deficiency (xerophthalmia).

Red flags.

• Shock, lethargy or reduced consciousness, hypothermia, hypoglycaemia or severe dehydration.
• Severe anaemia, jaundice, eye signs of vitamin A deficiency, or cough with fast breathing.
• No appetite (failed appetite test), persistent vomiting or severe infection.

• Clinical diagnosis from bilateral pitting oedema, with mid-upper-arm circumference, weight and length to define the severity of any wasting.
• Complicated disease: no appetite, medical complications or oedema grade 3 (generalised oedema including the face). Uncomplicated disease: good appetite and clinically well.
• Blood glucose on admission, malaria test where endemic, HIV test, haemoglobin, urine microscopy and culture, and chest X-ray. Albumin, potassium, magnesium and phosphate if available.
• Screen for tuberculosis, and for HIV in all children with severe acute malnutrition.

Differential diagnosis. Nephrotic syndrome, protein losing enteropathy, heart failure, liver disease, severe anaemia, hypothyroidism and allergic or angioedema.

Stabilisation phase (days 1 to 7).

• Treat hypoglycaemia (glucose under 3 mmol/L) with 10% glucose 5 mL/kg IV or oral glucose solution, then feed every 2 to 3 hours. Keep warm and treat hypothermia.
• Feed with a low lactose therapeutic milk providing 75 kcal and 0.9 g protein for each 100 mL, at 100 kcal/kg/day in 8 to 12 feeds.
• Do not give diuretics, and do not give IV fluids except in shock, because of the risk of heart failure. Oedema resolves with feeding.
• Dehydration: low sodium rehydration solution 5 mL/kg every 30 minutes for 2 hours, then 5 to 10 mL/kg/h alternating with feeds for up to 10 hours. For shock, 15 mL/kg of compound sodium lactate solution in 5% glucose over 1 hour, reviewed after each bolus.
• Antibiotics for all: amoxicillin 15 mg/kg orally every 8 hours for 5 days. For complicated disease: ampicillin 50 mg/kg IV every 6 hours with gentamicin 7.5 mg/kg IV once daily for 7 days, and adjust to the local pattern of resistance.
• Micronutrients: potassium 3 to 4 mmol/kg/day, magnesium 0.4 to 0.6 mmol/kg/day, zinc 2 mg/kg/day, copper 0.3 mg/kg/day, folic acid 5 mg on day 1 and then 1 mg daily, and vitamin A for eye signs (50 000 units under 6 months, 100 000 units at 6 to 12 months, 200 000 units over 12 months). Withhold iron until the infant is feeding and gaining weight.
• Treat infections, including malaria, HIV and tuberculosis.

Rehabilitation phase.

• Transition over 2 days to a therapeutic milk providing 100 kcal for each 100 mL, or ready-to-use therapeutic food, with a target intake of 150 to 220 kcal/kg/day and 4 to 6 g/kg/day of protein.
• Iron 3 mg/kg/day once appetite has returned, usually from week 2. Stimulation and play, and counselling for the carer.
• Discharge or transition to outpatient care when oedema is resolved, appetite is good, and the child is clinically well.

Monitoring. Weight daily, oedema, temperature, pulse and respiratory rate for early heart failure, and glucose in the first days. Weight gain over 5 g/kg/day indicates recovery.

Referral and escalation. Admit children with complications or no appetite, and refer to nutrition rehabilitation programmes. Test for and treat HIV.

Special groups. Infants under 6 months need breastfeeding support or relactation and inpatient care. Children with HIV or tuberculosis need concurrent treatment with adjusted timing.