INTRODUCTION. a. Background:

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1 INTRODUCTION a. Background: Protein Energy Malnutrition is a range of pathological conditions arising from coincident lack of protein and calories in varying proportions, occurring most frequently in infants and young children and usually associated with infections and deficiency of micro-nutrients. (WHO, 1973). These are conditions due to varying degrees of protein and calories deficiencies in which there is failure to maintain adequate weight gain or growth rate in the early stages but as the condition progresses, there is loss of weight associated with loss of subcutaneous fat and muscle mass. Resulting dysfunction of many vital organs leads to a variety of clinical features. With increasing severity there is increasing failure in the homeostatic mechanisms of the body and damage to the immune defences, which may result in infections and death. Mention of nutritional disorders in infants and children dates back as far as the sixteenth century under names such as macies, atrophy, atrepsy etc. Specific interest in what we now know as the syndromes of protein energy malnutrition (PEM) began early in this century. Zerny and Kellen in used the term 'mehlnährshaden' for infant malnutrition resulting from imbalanced (excess starch) feeding habit and had described a clinical picture similar to kwashiorkor. The term "Kwashiorkor" was used by the Ga Tribe of Accra, the capital of the Gold Coast (now Ghana) for the sickness of the weanling child. The term translated literally refers to a deposed child i.e. deposed from the breast when the next baby is born or when its mother again becomes pregnant. Cicely Williams (1933), while working in Gold Coast found a history of abnormal diet in all cases of kwashiorkor. They had been weaned into maize gruels that had low protein content and within 3-4 months children began to sicken. Williams considered kwashiorkor a protein deficiency, a question of proportion rather than of quantity. 1 (Brock and Autret (1952) in the WHO/ FAO reports, describing kwashiorkor as the "the most serious and widespread nutritional

2 disorder known to medical and nutritional science", firmly established the name kwashiorkor for the syndrome in Africa and its relationship to a low protein diet. 2 Soon later it became obvious that the disease affected poorly fed infant all over the world and was not confined to countries that may be described as tropical. The first detailed account about kwashiorkor was given by Trowell et al (1954) in his book which gives a excellent outline of what was known at the present time of the history, clinical signs, pathology and treatment of kwashiorkor. 3 Jelliffe (1959) proposed the term protein calorie (energy) malnutrition to cover the spectrum of syndromes that range from marasmus to kwashiorkor. 4 b. Global Scenario From the available evidence, PEM is an extremely serious problem in the developing regions of Asia, Africa and Latin America. According to WHO estimates, about one third of the world's children are affected by PEM, 76% of these children live in Asia (mainly southern Asia), 21 % in Africa and 3 % in Latin America. As many as 206 million children in developing countries are stunted which is associated with poor developmental attainment in children and functional impairment in adults. Apart from this, malnutrition is associated to a significant extent with a number of other childhood diseases, which are the major causes of childhood mortality in developing world. In 1997, there were 10.4 million deaths among children under 5 years of age, 97% of them in the developing world and most of them due to infectious diseases such as pneumonia and diarrhoea, combined with malnutrition. Fig. 1 Main causes of death among children under age 5, developing world,

3 Neonatal tetanus 0.4 (20%) Neonatal sepsis and meningitis 0.4 (30%) Birth trauma 0.4 (30%) Malnutrition (Excl. IUGR) 0.3 (100%) Diarrhoea 2.0 (70%) Congenital anomalies 0.5 (30%) Birth asphyxia 0.9 (35%) Measles 1.1 (65%) All other causes 0.2 (40%) Malaria 0.7 (40%) Tuberculosis 0.1 (60%) Pertussis 0.4 (50%) Prematurity 1.0 (40%) ALRI 2.1 (44%) Total Deaths: 10.4 million Percentages within the parentheses show the proportion of deaths, which is associated with malnutrition. c. National Scenario Nepal is one of the least developed countries in the world with poor demographic indicators. Under-five mortality in Nepal is 118 deaths per 1000 births, so 1 out of every 8 children born in Nepal will die before the fifth birthday. Approximately two out of three under-five deaths occur in the first year of life; infant mortality is 79 deaths per 1000 births. During infancy the risk of neonatal death (50 per 1000) is nearly twice as high as the risk of post-neonatal death (29 per 1000). 6 There is considerable malnutrition among children in Nepal. Forty-eight percent of children under age of 3 years are stunted, 11 percent are wasted and 47 percent are underweight. Variation by place of residence is marked with rural children, children living in the Mountains and in the Far-Western region of Nepal more likely to be malnourished than other children. 6 While stunting is very high

4 nationally, it is even higher in the mountain region. As many as five out of six children suffer from stunting in this region. 7 d. Aetiological Factors of PEM PEM is an ultimate result of many factors operating in children of underprivileged communities both in urban and rural areas. The basic feature of the high prevalence of PEM is the extreme inequality in the distribution of food among different socio-economic groups. It would not be unreasonable for a newcomer to the subject to assume that the term 'Protein Energy malnutrition' implied a well-established and simple aetiology. Deficiencies of protein and energy are indeed the major cause but there is a great deal more to the syndrome. In addition to shortage of protein and calorie, a number of epidemiological factors are implicated in the causation of PEM. Food shortage Low cash income High food prices Child ill Malnutrition Lack of knowlegeg Mother ill Many young children Heavy work on the or pregnant land Fig. 2 Multiple aetiological factors of PEM. 8 e. Effects of PEM on Structure and Functions of Organs In PEM, virtually every tissue and organ of body in affected to a variable extent. In the words of Alleyne (1966) 9 the heart does not escape the wasting that affects other organs'. With the help of autopsy, chest X-ray and echocardiography, the pathophysiological and histological changes in PEM has been studied by Tanman (1971) 10 in Turkey, Viart (1977, 1978) 11 in Zaire and later by Bergman et al (1988) 12. Though there is variation in values obtained perhaps because of technical reasons, there is decrease in cardiac output of around 30 percent in the malnourished compared with the recovered state. During recovery, cardiac output is increased mainly as a result of increase in stroke volume but also by a rise in heart rate. With the use of cardiac catheterization systemic and pulmonary arterial

5 pressure was found to be increased while peripheral resistance was found to be significantly increased 11. Most of the studies have shown a decrease of around 10 percent in plasma volume during PEM than those after recovery. A child with PEM typically has a moderate anaemia ( Hb8-10 gm%) with normocytic - normochromic or normocytic hypochromic picture. Bone marrow may show normal erythropoiesis or be fatty and hypoplastic The liver is one of the most important organs affected by PEM but especially so in case of kwashiorkor and fatty liver has been accepted as an important feature of kwashiorkor. There is fatty infiltration of the hepatocytes and resolution has been noticed in return to normal diet. 13 Fatty liver occurs in marasmus but to a lesser extent. In pancreas, the most important change is atrophy of the acinar calls with loss of zymogen granules. Changes in islets of Langerhans have not been observed in PEM, but the atrophy of the exocrine pancreas may lead to a fine fibrosis of the organ. The production of pancreatic enzymes is significantly impaired. In PEM significant alternations in gut have been described. There is decrease in villius height while crypts become elongated. Brunser et al (1968) 14 reported that in kwashiorkor the mucosa was completely flat while crypts were elongated. There is delay in replacement of the cells exfoliated from the villus tips. All these will result in decrease in absorptive capacity with preservation of secretory activity. The change in kidney is not very striking but in severe cases hyalinization of the glomeruli and cloudy swelling and necrosis of tubular cells has been reported. There is reduction in kidney weight (in parallel with the reduction of body weight), glomerular filtration rate and, renal plasma flow. In addition to it there is reduction in ability to excrete acids and sodium and to produce a concentrated urine. f. Biochemical Parameters for the Assessment of PEM

6 Along with clinical and anthropometric assessments, biochemical measurements are also carried out for the assessment of PEM in a hospital. The major objectives of biochemical tests or measurements on blood (and urine) according to Waterlow JC 15 are: a) As early and sensitive indicators of the development of PEM. b) As indicators of severity and prognosis. c) As aids to distinguish between kwashiorkor and marasmus. d) To provide information about underlying processes. e) For indirect assessment of food intake