Protein-energy malnutrition (PEM) is a form of undernutrition from an insufficient intake of dietary protein, energy, or both. It primarily affects children in developing countries and is often linked to social, economic, and environmental factors that lead to inadequate food supplies. PEM exists on a spectrum with two severe forms: kwashiorkor and marasmus. While both are serious, they stem from different nutritional deficiencies and present with unique clinical signs.
Understanding Kwashiorkor
Kwashiorkor develops in a child who consumes enough calories but not enough protein. This often occurs when a child is weaned from protein-rich breast milk to a diet high in carbohydrates, such as maize or rice. This dietary shift creates a significant protein deficit, even if the total energy intake is sufficient. The condition is frequently seen in regions where staple foods are low in protein.
The most prominent sign of kwashiorkor is generalized edema, which is swelling caused by fluid retention in the abdomen, legs, and feet. This swelling can mask the true extent of muscle and fat loss, making the child appear plump. The lack of protein impairs the body’s ability to maintain fluid balance, causing fluid to leak from blood vessels into surrounding tissues.
Other signs relate to changes in skin and hair. A child with kwashiorkor may develop “flaky-paint dermatosis,” where the skin darkens and peels away in patches. Hair may become dry, brittle, and change color to a reddish-yellow or gray. The liver often becomes enlarged with fatty deposits due to impaired fat metabolism.
Understanding Marasmus
Marasmus results from a severe deficiency of all nutrients, including proteins, carbohydrates, and fats. It is a state of starvation where the body does not receive enough energy to sustain basic functions. This condition is common in infants and young children who experience prolonged periods of insufficient food intake, such as a lack of breast milk without a suitable replacement.
The physical appearance of a child with marasmus is one of severe emaciation. There is a significant loss of muscle mass and subcutaneous fat, which leaves the child looking like “skin and bones” with prominent ribs and loose, wrinkled skin. The face may take on an aged appearance.
Edema is absent in marasmus, and the child’s body weight is less than 60% of what is expected for their age. Despite their frail physical state, children with marasmus are often alert and may have a notable appetite if food is offered. Their disposition is frequently irritable and fretful.
Key Distinctions
The presence of edema in kwashiorkor versus its absence in marasmus is the most visible dividing line between the two conditions. This core distinction is driven by the different underlying nutritional deficiencies.
Body composition also differs significantly. In kwashiorkor, some subcutaneous fat may be preserved, and the swelling can cause the child’s weight to be between 60% and 80% of the normal weight for their age. A child with marasmus has virtually no subcutaneous fat, and their body weight is characteristically below 60% of the norm.
Internal organ changes and behavioral attributes further separate the two conditions. An enlarged, fatty liver is a common finding in kwashiorkor but not in marasmus. A child with kwashiorkor is often apathetic with a poor appetite, while a child with marasmus can be alert and may exhibit a voracious appetite.
Medical Management and Recovery
Treating severe malnutrition is a phased process that requires medical care. The first priority is stabilization, which involves correcting dehydration, electrolyte imbalances, and treating any coexisting infections. During this phase, aggressive feeding is avoided to prevent refeeding syndrome, a dangerous complication from reintroducing nutrients too quickly.
Once the child is stabilized, feeding begins with small, frequent amounts of a specially formulated therapeutic milk. The diet is gradually advanced to provide enough energy and protein to support catch-up growth. This nutritional rehabilitation aims to restore lost body tissues and requires careful monitoring.
Long-term recovery involves providing caregivers with education on appropriate child feeding practices and ensuring access to a balanced diet to prevent relapse. While effective treatment can lead to recovery, some children may face long-term physical and cognitive challenges. The mortality rate for PEM can range from 5% to 40%, depending on the severity and availability of medical care.