nutritional disorders
Protein Energy Undernutrition (PEU)
Classification and Etiology of PEU
PEU is graded as mild, moderate, or severe. Grade is determined by calculating weight as a percentage of expected weight for length or height using international standards (normal, 90 to 110%; mild PEU, 85 to 90%; moderate, 75 to 85%; severe,<75%). PEU may be Primary: Caused by inadequate nutrient intake Secondary: Results from disorders or drugs that interfere with nutrient use Worldwide, primary PEU occurs mostly in children and older people who lack access to nutrients, although a common cause in older people is Depressive Disorders . PEU can also result from fasting or In children, chronic primary PEU has 3 common forms: Marasmus Kwashiorkor Marasmic kwashiorkor The form depends on the balance of nonprotein and protein sources of energy. Starvation is an acute severe form of primary PEU. Marasmus(also called the dry form of PEU) is a severe deficiency of calories and protein that tends to develop in infants and very young children. It causes weight loss and depletion of fat and muscle. In marasmus, most of the body's subcutaneous fat and deeper fat stores are lost, making the ribs, hips, facial bones, and spine visible through the skin. In countries with high rates of food insecurity, marasmus is the most common form of PEU in children. (also called the wet, swollen, or edematous form) is a risk after premature abandonment of breastfeeding, which typically occurs when a younger sibling is born, displacing the older child from the breast. So children with kwashiorkor tend to be older than those with marasmus. Kwashiorkor may also result from an acute illness, often Overview of Gastroenteritis or another infection (probably secondary to cytokine release), in a child who already has PEU. A diet that is more deficient in protein than energy may be more likely to cause kwashiorkor than marasmus. Less common than marasmus, kwashiorkor tends to be confined to specific parts of the world, such as rural Africa, the Caribbean, and the Pacific islands. In these areas, staple foods (eg, yams, cassavas, sweet potatoes, green bananas) are low in protein and high in carbohydrates. Children with kwashiorkor have stunted growth; unnaturally blond, sparse, and brittle hair; and discolored patches of skin. In kwashiorkor, cell membranes leak, causing extravasation of intravascular fluid and protein, resulting in peripheral edema. Marasmic kwashiorkoroccurs when a child with kwashiorkor does not consume enough calories. It is characterized by features of marasmus and kwashiorkor—edema and wasting. In both marasmus and kwashiorkor, cell-mediated immunity is impaired, increasing susceptibility to infections. Bacterial infections (eg, Overview of Pneumonia , Starvationis a complete lack of nutrients. It occasionally occurs when food is available (as in fasting or anorexia nervosa) but usually occurs because food is unavailable (eg, during famine or wilderness exposure). This type most commonly results from the following: Disorders that affect gastrointestinal function:These disorders can interfere with digestion (eg, pancreatic insufficiency), absorption (eg, enteritis, enteropathy), or lymphatic transport of nutrients (eg, retroperitoneal fibrosis, Milroy disease). In disorders with wasting (eg, Human Immunodeficiency Virus (HIV) Infection , These conditions include Manifestations of Infection , 