Kwashiorkor

Kwashiorkor was first described in Ghana, in west Africa, in 1932 — the word is the Ghanaian name for the condition. In addition to the wasting of muscle tissue, loss of intestinal mucosa and impaired immune responses seen in marasmus, children with kwashiorkor show a number of characteristic features which distinguish this disease  

The underlying cause of kwashiorkor is an inadequate intake of food, as is the case for marasmus. Kwashiorkor traditionally affects children aged between of 3 and 5 years. In many societies a child continues to suckle until about this age, when the next child is born. As a result, the toddler is abruptly weaned, frequently onto very unsuitable food. In some societies, children are weaned onto a dilute gruel made from whatever is the local cereal in others the child may be fed on the water in which rice has been boiled - it may look like milk, but has little nutritional value. Sometimes the child is given little or no special treatment but has to compete with the rest of the family for its share from the stew-pot. A small child has little chance of getting an adequate meal under such conditions, especially if there is in any case not much food for the whole family. 

Very commonly, an infection precipitates kwashiorkor in children whose nutritional status is inadequate, even if they are not yet showing signs of malnutrition. Indeed, paediatricians in developing countries expect an outbreak of kwashiorkor a few months after an outbreak of measles. 

The most likely precipitating factor is that, superimposed on general food deficiency, there is a deficiency of the antioxidant nutrients such as zinc, copper, carotene and vitamins C and E (section 7.4.3). As discussed in section 7.4.2.2, the respiratory burst in response to infection leads to the production of oxygen and halogen radicals as part of the cytotoxic action of stimulated macrophages. The added oxidant stress of an infection may well trigger the sequence of events that leads to the development of kwashiorkor. 

Once the patient has begun to develop a more normal intestinal mucosa (when the diarrhoea ceases), ordinary foods can gradually be introduced. Recovery is normally rapid in children, and they soon begin to grow at a normal rate. 

---

Organoselenium compounds in particular, once ingested, are slowly released over prolonged periods and result in foul-smelling breath and perspiration. The element is also highly toxic towards grazing sheep, cattle and other animals, and, at concentrations above about 5 ppm, causes severe disorders. Despite this, Se was found (in 1957) to play an essential dietary role in animals and also in humans — it is required in the formation of the enzyme glutathione peroxidase which is involved in fat metabolism. It has also been found that the Incidence of kwashiorkor (severe protein malnutrition) in children is associated with inadequate uptake of Se, and it may well be involved in protection... 

All 20 of the amino acids present in proteins are essential for health. While comparatively rare in the Western world, amino acid deficiency states are endemic in certain regions of West Africa where the diet relies heavily on grains that are poor sources of amino acids such as tryptophan and lysine. These disorders include kwashiorkor, which results when a child is weaned onto a starchy diet poor in protein and marasmus, in which both caloric intake and specific amino acids are deficient. 

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

Diseases of people come in many flavors. There are infectious diseases (measles, mumps, influenza, AIDS,...), nutritional deficiency diseases (scurvy, beriberi, kwashiorkor,...), degenerative diseases (Alzheimer s disease, osteoporosis,...), cancer (of the lung, breast, prostate, liver,...), and single-gene inherited diseases or molecular diseases. In the last category, an important and instructive example is provided by sickle cell anemia. Let s consider this disease and begin to develop a sense of how we can understand it on the basis of what we now know about proteins. 

A special form of undemutrition that particularly affects children is known as protein-energy malnutrition (PEM) which is a spectrum of syndromes from marasmus (lack of energy intake) to kwashiorkor (deficient protein intake). 

Malnourished children can have two very different appearances. In marasmus, the limbs are wasted and the whole of the body assumes a shrunken skin and bone appearance, as muscle is sacrificed to support more vital tissues. The shranken cheeks are caused by a loss of the Bidet fat depots, hi kwashiorkor, children have pot-bellies partially explained by generalised oedema and hepatomegaly. Both have brittle, bleached hair, skin lesions and a deeply apathetic demeanour. Although the two conditions intergrade they show some geographical separation with kwashiorkor being restricted to tropical and subtropical regions while marasmus can occur anywhere. 

Marasmus is considered to be due to inadequate food intake. It is not usually the quantity but the quality of the food that is deficient, e.g. low nutritional value of bulky vegetables. Kwashiorkor is considered to be caused, more specifically, by a low-protein diet. This condition frequently develops at the time of weaning when protein-rich milk is replaced by protein-deficient solid food. It did not appear in the medical literature until 1934 when it was reported by Cicely Williams who studied the condition while she was working among tribes of Western Africa. She gave it the name kwashiorkor, which was used by the Ga tribe to describe the condition that develops when the baby is taken away from mother s breast, usually because another baby has been bom. It has generally been held that the oedema is a consequence of a low plasma albumin concentration and a reduction in the colloid osmotic pressure which reduces the movement of water from tissue fluid back into capillaries. The low albumin level results from a decreased rate of synthesis of albumin by the liver. However, if marasmus is due entirely to lack of energy... 

Donbts have, however, been expressed about protein deficiency being the sole cause of kwashiorkor. There is only a poor connection between its occurrence and the protein content of the diet and recovery from kwashiorkor is not simply related to protein consumption. Other factors may be involved, such as ... 

The serum protein concentrations, especially of albumin, are low in kwashiorkor but normal in marasmus. 

The plasma fatty acid levels are increased in both but especially in kwashiorkor. 

Fatty liver occurs in kwashiorkor, probably due to lack of protein in the diet, which reduces the synthesis of the structural protein for VLDL (apolipoprotein B). The increased triacylglycerol produced in the liver from fatty acids removed from the blood (i.e. the inter-tissue triac-... 

The ratio of essential to non-essential amino acids is high in kwashiorkor but normal in marasmus. The cause of this may be low activities of the enzymes for metabolising the essential amino acids. These are required for any protein synthesis that must take place even in kwashiorkor. 

Serum Ig Levels in Young Infants with Kwashiorkor. 167... 

The joining chain (J in Figs. 1 and 2) is attached to IgA in the submucosa, forming the 10 S dimer which, by the process of pinocytosis, enters the mucosa and there becomes attached to the secretory component (SC), giving rise to the 11 S dimer. Secretory component prevents hydrolysis of S IgA in the lumen of the gut. The 7 S IgA monomer does not become attached to the J chain but enters the circulation via the venous-lymphatic circulation. This physicochemical property of IgA probably accounts for its relatively increased values in the serum of some children with kwashiorkor. 

In Egyptian children with kwashiorkor whose clinical disease became apparent before 7 months of age there was a regular long-delayed and... 

Using semiquantitativc immunoclectrophoresis in 21 Egyptian children with kwashiorkor without evidence of infections, serum IgG precipitin arcs were more or less unchanged and were similar to the normal pattern. Thirteen of the children with severe kwashiorkor had serum IgM precipitin arcs that were shorter and less dense than the normal arcs. The majority of the rest had normal scrum IgM lines. Eighteen of the chil-... 

Refer- ence Country Number of subjects Kwashiorkor patients Controls Age (months) IgG IgA IgM... 

---