Pediatric Nutrition in Practice

140 Shahrin  Chisti  Ahmed

body’s demand for them to ensure growth, main-
tenance and specific functions [1].
Primary malnutrition in children is most com-
monly seen in low- and middle-income countries.
The factors responsible for primary malnutrition
include household food insecurity, poverty, poor
nutrition of women during pregnancy, intrauterine
growth restriction, low birth weight, poor breast-
feeding and inappropriate complementary feeding,
frequent infectious illnesses, poor quality of water,
sa n it at ion a nd hyg iene, etc. Most c a ses of ma l nut r i-
tion seen across the globe are primary in nature.
Although there is enough food in the world to feed
all, it is sad to see hunger and malnutrition ravage
through many countries primarily because of ineq-
uity and inequality affecting access to nutritious
food. The problem of primary malnutrition is,
therefore, mostly social rather than biomedical in
origin. It is also multifactorial. For example, poor
water quality, sanitation and hygiene practices are
increasingly believed to be the cause of the condi-
t ion ca l led ‘env iron menta l enteropat hy’ t hat resu lts
in children becoming stunted [2]. A child who is
repeatedly exposed to pathogens in the environ-
ment has bacterial colonization of the small intes-
tine. There is an increased accumulation of inf lam-
matory cells in the small intestinal mucosa, the in-
testinal villi are damaged and distorted by the
inflammatory process, and, consequently, they
malabsorb nutrients, which results in malnutrition.
Chronic inf lammatory processes also suppress the
production of IGF-1, upset the growth hormone
axis and lead to linear growth retardation [3].
Secondary malnutrition, in contrast, results
from an underlying disease that compromises
growth directly or through its deleterious effect
on appetite or the absorption of nutrients. The
underlying disease can cause poor appetite as a
result of a release of inf lammatory mediators in-
cluding TNF-α; the disease also affects nutrition-
al status by inducing a catabolic state in the body.
Infectious illnesses result in malnutrition by re-
ducing the intake of nutrients and their bioavail-
ability, by increasing nutrient and energy expen-

diture and by diverting nutrients away from

growth. In patients with extensive burns, in-

creased catabolism, anorexia and loss of plasma

proteins from the exposed skin surfaces lead to

malnutrition. Nutrient loss in Crohn’s disease

and increased energy expenditure in congenital

heart disease also contribute to malnutrition.

The main cause of malnutrition seen in devel-

oped countries is secondary malnutrition. If not

identified early on, or if left untreated, secondary

malnutrition increases the risk of infection, de-

layed wound or burn healing and an overall poor

response to treatment of the underlying cause.

Table 1 lists common conditions that can lead to

secondary malnutrition, although not all of them

are commonly seen in developed countries.

The Burden of Malnutrition

Globally, an estimated 165 million children <5

years of age (or 26%) were stunted (height-for-age

Z score ≤ –2 based on the WHO Child Growth

Standards) in 2011 [4]. The estimated number of

underweight children (weight-for-age Z score

<–2) globally is 101 million or 16%. Wasting af-

fects 52 million children <5 years of age, which is

8% of all children of that age group. Severe wasting

or severe acute malnutrition (SAM), defined as a

weight-for-height Z score <–3, affects nearly 19

million children, with a global prevalence of 2.9%.

Stunting is the cause of 14.7% of deaths in children

<5 years old. Underweight is responsible for 14.4%

of deaths, while wasting kills 12.6% of the children

<5 years of age. It has been estimated that fetal

growth restriction, stunting, wasting and deficien-

cies in vitamin A and zinc along with suboptimal

breastfeeding cause 3.1 million child deaths annu-

ally or 45% of all child deaths in 2011. The overall

risks of mortality from any cause (diarrhea, pneu-

monia, malaria or measles) for severe stunting, se-

vere wasting and severe underweight are 4.1, 9.4

and 9.7, respectively. Among those who survive,

impaired intellectual or cognitive and motor de-

Koletzko B, et al. (eds): Pediatric Nutrition in Practice. World Rev Nutr Diet. Basel, Karger, 2015, vol 113, pp 139–146

DOI: 10.1159/000367880