Protein-energy malnutrition, sometime referred to as protein-energy undernutrition, generally manifests as marasmus, kwashiorkor or starvation, according to Merck Manuals. Marasmus is caused by an overall caloric- intake deficiency, and is characterized symptoms of fat and muscle tissue loss. Kwashiorkor is caused specifically by protein deficiency with symptoms of tissue swelling.
Protein-calorie malnutrition that results in kwashiorkor is identifiable by swelling in the feet, ankles, abdomen and liver. Additionally, tooth loss, skin depigmentation, thinning hair and dermatitis are reported to be symptoms by Wikipedia. Children suffering from kwashiorkor may develop anorexia, according to Wikipedia. Physical and mental development are severely impacted by prolonged kwashorikor. In severe, untreated cases, kwashiorkor can lead to shock or coma, notes Healthgrades.
Marasmus, sometimes referred to as "wasting" or "wasting-away," is a result of both dietary protein deficiency and overall caloric deficiency, explains Healthgrades. The primary characteristic of marasmus is the degradation of fat, muscle and other bodily tissue. Symptoms include dizziness, a distended abdomen, fatigue, dry or peeling skin, an emancipated appearance and chronic diarrhea.
Protein-energy malnutrition occurs most frequently in developing regions of the world, especially during famine conditions, but also occurs in developed countries in poor, urbanized areas. Protein energy malnutrition may also occur as a result of a variety of diseases, including cystic fibrosis, intellectual disability, cardiovascular disease and neurological disease, according to Wikipedia.