In addition, malnutrition is frequently classified on the basis of deficits of weight-for-age (w/a) or height-for-age [Gomez, et al., 1955], [Water Low J.; et al., 1977]. In this system, children are classified into groups according to malnutrition severity based on their weight compared to the weight average for their age.
1. First degree or mild cases of malnutrition include children whose weight
76-90% of averaged weight.
76-90% of averaged weight.
2. Children with the second degree or moderates cases have weights between 61-75% of the average, and
3. Children with third degree of severe malnutrition weight 60% or less than their peers (Gomez, F.; et al., 1955].
With time, the so called “Gomez classification” has been used widely both to classify individual children for clinical referral and to assess malnutrition in communities [de Onis, M.; et al., 2000]. The satisfaction of malnutrition as mild, moderate or severe has helped to systematize clinical observation and has allowed for the comparison of finding between different researchers [Arroyo, P.; and Mandujanb Cravioto (1922-1998), 2000]. Moreover, the risk of death is directly correlated with the degree of malnutrition [Van den Brock, J.; et al., t 1993].
In developing countries about 3.5% of children under the age 5 of suffer from severe malnutrition. Although mild and moderate types of childhood malnutrition are even more prevalent, their significance in childhood morbidity and mortality is less well recognized [Ahmed, T.; et al., 2009].
Severe PCM appears in the principal clinical forms
1. Marasmus, characterized by chronic wasting condition and a gross underweight status that is habitant, associated with early weaning;
2. Kwashiorkor, characterized by moderate growth retardation, changes to hair and skin color, edema, moon facies, and hepatosplenomegaly; and
3. Merasmic kwashiorkor, characterized by severe wasting and the presence of edema.
Marasmus appears by caloric and protein in sufficiency whereas kwashiorkor develops from protein deficiency [water low, J. C. 1996]
Epidemiological and experimental observations have proven that malnourished children are more susceptible to infectious disease; therefore PCM is considered a strong risk factor for higher morbidity and mortality rates in infectious diseases [Wiodward, B., 1998]. Several studies on the effect of malnutrition at the immunological level been conducted in humans and in experiment animal models. Multiple immune system abnormalities, including lymphoid organ atrophy, profound T-cell deficiency, altered ratios of T-cells function, cytokine production and the ability of lymphocytes to respond appropriately to cytokines. In several malnourished children, both acquired immunity as well as innate host defense mechanism are affected [Bhaskaram, P. 1992]; [Rodrguez, L.;. et al., 2005].
In children under 5 years of age, malnutrition is responsible, directly or indirectly, for 54% of the 10.8 million death per year and contributes to every second death (53%) associated with infectious disease among this age group in developing countries (figure 2) [Benguiui, Y.; and Stein, F. 2005]. Additionally, mud and moderate forms of malnutrition primarily account for the burden of malnutrition world wide. For the surviving children, malnutrition has lifelong implications because it severely reduces child ability to learn and grow their full potential. Thus malnutrition leads to less productive adults and weaker national economic performance [Benguigui, Y.; and Stein, F .2006].
Figure 2: Distribution of 0.5 million deaths among children younger than 5 years of age in all developing countries. Adapted from Benguigui and stein [Benguigui, Y.; Sten, F. integrated management of childhood illness: An emphasis on the management of infectious diseases Sem.prediatr. infect. Dis. 2006, 17, 80-98].
The malnutrition infection complex can be viewed under two aspects, malnutrition compromising host defense, or infection either aggravating existing, deficient nutrition status or triggering malnutrition through diseases pathogenesis. Malnutrition can facilitate pathogen invasion and propagation; further, it can increase the probability of secondary infection occurring thus modifying both disease pathogenesis and prognosis [Borelli, P.; et al., 2004]. Certain infectious diseases also cause malnutrition. It appears in that there is a vicious cycle involved, where malnutrition increases disease susceptibility and diseases cause reduction in food intake.