Malnutrition Protein deficiency

PROTEIN MALNUTRITION. Protein deficiency is common worldwide. This is primarily because in many underdeveloped areas of the world protein intake is marginal, but energy intake is so low that the protein eaten is not spared for its essential functions. The name, protein-energy (calorie) malnutrition is applied to a whole spectrum of protein and energy deficiencies. At one end of the spectrum is kwashiorkor—a severe clinical syndrome caused by a deficiency of protein. Pertinent protein malnutrition information follows ... 

In arterioles, the hydrostatic pressure is about 37 mm Hg, with an interstitial (tissue) pressure of 1 mm Hg opposing it. The osmotic pressure (oncotic pressure) exerted by the plasma proteins is approximately 25 mm Hg. Thus, a net outward force of about 11 mm Hg drives fluid out into the interstitial spaces. In venules, the hydrostatic pressure is about 17 mm Hg, with the oncotic and interstitial pressures as described above thus, a net force of about 9 mm Hg attracts water back into the circulation. The above pressures are often referred to as the Starling forces. If the concentration of plasma proteins is markedly diminished (eg, due to severe protein malnutrition), fluid is not attracted back into the intravascular compartment and accumulates in the extravascular tissue spaces, a condition known as edema. Edema has many causes protein deficiency is one of them. 

Types of protein-energy malnutrition are marasmus (deficiency in total intake or nutrient utilization), kwashiorkor (relative protein deficiency), and mixed marasmus-kwashiorkor. 

The amonnt of protein synthesised and then released in (iv) and (v) is abont 70 g each day. Even under conditions of starvation or malnutrition, proliferation and differentiation of stem cells located in the crypts of the villi are important to provide the cells necessary for replenishment of those lost from the villi. New cells move up the villus to replace those lost at the top. Under these conditions, amino acids are not available from the intestine and have to be taken up from the blood across the basolateral membrane. A low level of amino acids in the blood, due to chronic malnutrition, will prevent or reduce the rate of proliferation of these cells, so that digestion of even the small amount of food ingested during malnutrition, or refeeding after starvation, is difficult. A vicious circle thus results from protein-deficient diets which increase the risk of development of protein-energy-malnutrition. This is especially severe in children but may also contribute to the clinical problems that occur in the elderly whose diets are of low quality. 

The antibody response to yellow fever vaccine was impaired in protein-deficient children with kwashiorkor compared to the well-nourished controls. Polio antibody production was normal in the malnourished children, all of whom also responded in the normal fashion to smallpox vaccination. They had no evidence of disseminated vaccinia (B8). In Guatemala, on the other hand, smallpox vaccination of children who had fully recovered from severe protein-calorie malnutrition led to a drop in their nitrogen retention with the added complication of disseminated vaccinia (V3). 

The atrophied changes of the thymolymphatic system is thought to be in part due to the high levels of plasma glucocorticoids in malnutrition (M12, S4, S12). In accordance with this view is the observation that protein-deficient rats had a very marked increased uptake of 1,2- H2-... 

As pointed out by Anderson et al. (15), starvation, malnutrition, and protein deficiency may all cause differences in drug disposition and thereby differences of drug action. Even relatively minor food deficiencies as observed in Berlin after the second World War (16) caused some unusual reactions, e.g., death from injection of the old and generally safe local anesthetic drug procaine (17). 

Kwashiorkor is a type of malnutrition associated with insufficient protein intake, usually affecting children aged 1-4 years, although it can also occur in older children and adults. It is likely caused by a combination of factors (protein deficiency, energy and micronutrient deficiency). The absence of lysine in low-grade cereal proteins (used as a dietary mainstay in many underdeveloped countries) can lead to kwashiorkor. 

There is a wide variation of deficiencies between energy and protein deficient diseases as in the cases described by marasmus and kwashiorkor. The term protein-energy malnutrition (PEM) is used to describe those differences. PEM is the result of poverty as well inadequate information on diet. In some countries there is the mistaken belief that the child should not be given high protein food, which is served to the father, while the child drinks the fluid the meat was cooked in. 

Animal experiments have shown that faulty nutrition, i.e. > 90% fat, < 10% protein and < 2 mg choline per day, leads to pronounced fatty fiver and even fatty cirrhosis within a few weeks. The same changes could be observed when the protein intake remained more or less normal, while extremely little methionine and choline was offered. With a partial surplus of certain foodstuffs, the special nature of the excessive nutritional components is also of considerable importance. The term partial malnutrition may, for example, be associated with a pronounced protein deficiency (and thus possibly inadequate production of lipoproteins) or a lack of lipotropic substances (such as methionine, choline, cystine, glycocoUbetaine, pyridoxine, casein and various N- or S-methylated substances). Protein deficiency has particularly severe consequences when toxic substances are absorbed at the same time or when the organism has to fight bacterial or parasitic infections. A diseased liver reacts to both a serious deficiency in and an excessive supply of different nutrients (e.g. proteins, certain kinds of amino acids, various lipids, trace elements) with unfavourable or even complicative developments during the course of disease. 

Severe malnutrition is a complex problem. Factors involved include the overall availability of food the availability only of starchy protein-deficient foods and contaminated water supplies, infants and young children are special targets because they are rapidly growing, are unusually susceptible to infections, and may not be able to find food for themselves. 

It has to be mentioned that non-genetic or environmental influences may also have great impact. Starvation, malnutrition, and protein deficiency can all cause a decreased rate of drug disposition, but so can even relatively minor food deficiencies. Some foods or drugs cause enzyme induction and others... 

Selenium sulfide is used as an antiseborrheic agent and as a shampoo in the treatment of Tinea versicolor. Selenite is also found in mineral supplements and is used in parenteral nutrition. However, selenium has gained undeserved popularity as a constituent of health foods and alternative tonics, perhaps because selenium deficiency has been implicated in the pathogenesis of some forms of malnutrition in children. However, even in children with selenium deficiency the benefit to harm balance has not been estabhshed. Indeed, in protein deficiency it seems to be particularly toxic. Nor is there any serious basis for its reputation as a remedy for cystic fibrosis, to prevent aging, or as a sexual stimulant. 

At special risk of vitamin A toxicity are those whose liver function is compromised by drugs, viral hepatitis, or protein-energy malnutrition (12). Elderly people may also be at increased risk for similar reasons but also from different causes. In addition to protein deficiency, alcohol intake and co-existing liver and renal disease may be present (86). 

Measurements of the levels of semm proteins such as albumin, transthyretin (also known as prealbumin), transferrin and retinol-binding protein are used as biochemical parameters in the assessment of protein energy malnutrition (Table 17-1). An ideal protein marker should have rapid turnover and present in sufficiently high concentrations in semm to be measured accurately. Transthyretin has these properties it is a sensitive indicator of protein deficiency and is effective in assessing improvement with refeeding. 

ALB was one of the first identified biochemical markers of malnutrition and has long been used in population studies. ALB is a relatively insensitive index of early protein malnutrition because there is a large amount normally found in the body (4 to 5 g/kg of body weight), it is highly distributed in the extravascular compartment (60%), and it has a long half-life (18 to 20 days). However, chronic protein deficiency in the setting of adequate nonprotein calorie intake leads to marked hypoalbuminemia because of a net ALB loss from the intravascular and extravascular compartments (kwashiorkor). Serum ALB concentrations also are affected by moderate-to-severe calorie deficiency hepatic, renal, and GI disease and infection, tramna, stress, and burns. In many cases, interpretation of serum ALB concentrations relative to nutrition status is difficult however, a positive correlation between decreased serum ALB concentrations and poor clinical outcome has been demonstrated in a variety of settings. Additionally, serum ALB concentrations of 2.5 g/dL or less can be expected to exacerbate ascites and peripheral, pulmonary, and GI mucosal edema due to decreased colloid oncotic pressure. 

Pure red cell aplasia that responded to the administration of riboflavin was reported in patients with protein depletion and complicating infections. Nutritionists induced riboflavin deficiency in human beings and demonstrated that a hypoproliferative anemia resulted within a month. The spontaneous appearance in human beings of red cell aplasia due to riboflavin deficiency undoubtedly is rare, if it occurs at all. It has been described in combination with infection and protein deficiency, both of which are capable of producing a hypoproliferative anemia. However, it seems reasonable to include riboflavin in the nutritional management of patients with gross, generalized malnutrition. 

The term kwashiorkor refers to a disease originally seen in African children suffering from a protein deficiency. It is characterized by marked hypoalbuminemia, anemia, edema, pot belly, loss of hair, and other signs of tissue injury. The term marasmus is used for prolonged protein-calorie malnutrition, particularly in young children. 

By analogy with the effects of malnutrition and sulfur enrichment on the high-sulfur proteins of the keratin-associated proteins in wool fiber [44,45], these effects of a lower cystine content in hair are probably a result of a decreased synthesis of the sulfur-rich proteins because of malnutrition. Studies of the effects of diet in persons suffering malnutrition (i.e., protein deficiencies) show that diet supplementation can influence the protein composition of human hair. However, such effects have only been demonstrated among persons suffering from severe malnutrition and never among healthy persons on a normal diet see the section on the keratin-associated proteins of human hair later in this chapter. 

A negative nitrogen balance represents a state of protein deficiency, in which the body is breaking down tissues faster than they are being replaced. The ingestion of insufhcient amounts of protein, or food with poor protein quality, cau result in serious medical conditions in which an individual s overall health is compromised. The immune system is severely affected the amount of blood plasma decreases, leading to medical conditions such as anemia or edema aud the body becomes vulnerable to infectious diseases and other serious conditions. Protein malnutrition in infants is called kwashiorkor, and it poses a major health problem in developing countries, such as Africa, Central and South America, and certain parts of Asia. An infant with kwashiorkor suffers from poor muscle and tissue development, loss of appetite, mottled skin, patchy hair, diarrhea, edema, and, eventually, death (similar symptoms are preseut in adults with protein deficiency). Treatment or prevention of this condition lies in adequate consumption of protein-rich foods [106]. 

The concept advanced by Marsh and Drabkin that protein deficiency leads to hyperlipoproteinemia does not seem to apply to other protein-deficiency states such as cirrhosis of the liver (Man et al. 1945), malnutrition (Man and Gildea, 1938), kwashiorkor (Schwartz and Dean, 1957), or idiopathic hypoalbuminemia (Gordon et al, 1959). It should be pointed out, however, that the conclusions by Marsh and Drahkin were based on experiments conducted in the early stage of experimental... 

K. is common in hot, humid areas, but not in dry. hot areas. It is especially prevalent in the wet season. Furthermore, it is never found in temperate regions. These observations suggest the contribution of other factors, in addition to protein deficiency. There is now strong evidence that K. is caused by a combination of malnutrition and aflatoxin poisoning [R. G. Hendrickse, British Medical Journal (1982) 843-846 S.M.Lamplugh R.G. Hendrickse, Annals... 

Protein deficiency see Protein-energy malnutrition, Kwashiorkor, Marasmus. 

Among the various forms of malnutrition that continue to afflict the human race, protein deficiency is one of the most common. Typical of protein deficiency is kwashiorkor. Although the condition is frequently seen, its pathogenesis remains poorly understood and requires appropriate knowledge of the fate of dietary proteins. 

The total body water content increases in patients with severe protein malnutrition. The increase involves both the extracellular fluid, in which the water content may rise up to 400 ml/kg compared to 250 ml/kg in normal individuals, and in the intracellular fluid, in which the water content may reach values above 80%, compared to the normal 67% values in normally fed individuals. Fluid accumulation in the extracellular tissues leads to edema. The severity of the edema may be masked somewhat by the loss of body solids and fats. However, in the later stages of the disease, edema becomes obvious. The edema fluid is not distributed uniformly throughout the body of the victim—swelling usually starts in the inferior limbs, probably as a result of gravity and deficient circulation. The back of the hand and the face are frequently swollen. A patient with kwashiorkor— particularly an older patient— may have edema in the lower part of the body and be dehydrated in the upper part. In younger children, this does not occur because the upright position is not maintained constantly and does not play such an important role in the accumulation of fluid in the inferior limbs. The pathogenesis of the edema in protein deficiency is discussed in the section on body fluids. 

Anomalies in the secretion of the antidiuretic hormone and aldosterone have been implicated in the pathogenesis of this protein-deficient edema. However, little convincing information is clinically available, and the experimental data are still controversial. An increase in the available amounts of antidiuretic hormone has been suggested to occur in malnutrition as a result of the inability of the liver to break down the antidiuretic hormone. 

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