Page 62 - Coespu 2019-1

MEDICAL

during acute measles infection fur- nerates higher returns than do tra- tract infections, reduces mortality
ther deteriorated the condition of de liberalization or malaria, water, from diarrhea, and enhances im-
malnourished children, leading to and sanitation programs. Vitamin munity. Measles also depletes the
further weight loss, wasting, and A maintains the integrity of the epi- body’s supply of vitamin A. Thus,
reduced serum levels of essen- thelium in the respiratory and ga- vaccination against measles often
tial amino acids. Increased ener- strointestinal tracts. The World He- includes a high dose of vitamin
gy consumption due to immune alth Organization estimates that, A. Vitamin E is an antioxidant that
responses may also affect the ef- worldwide, 100–140 million chil- scavenges free radicals. Vitamin E
ficacy of live attenuated vacci- dren are vitamin A deficient, cau- supplementation has been shown
nes in populations ridden with sing 1.2–3 million deaths per year. to improve immune function in the
PEM. Arginine treatment has Vitamin A deficiency increases the elderly, with delayed hypersensi-
been shown to improve nitrogen risk of diarrhea, Plasmodium fal- tivity skin response and antibody
balance and lymphocyte function ciparum malaria, measles, and production after vaccination. Vita-
and stimulate arginine transport in overall mortality. Vitamin A defi- min E increases both cell-dividing
the liver. These benefits have made ciency and measles, which is esti- and interleukin-producing capaci-
arginine an essential constituent of mated to kill 2 million children per ties of naive T cells but not of me-
immunonutritive formulas current- year, are closely linked. Measles in mory T cells. This enhancement of
ly in use for critically ill patients. In a child is more likely to exacerba- immune function is associated with
added to amminoacid arginine, te any existing nutritional deficien- significant improvement in resi-
important to the immune system, cy, and children who are already stance to influenza virus infection
are micronutrients, including vi- deficient in vitamin A are at much in aged mice and a reduced risk
tamins A, C, and E and minerals greater risk of dying from measles. of acquiring upper respiratory in-
like zinc, iron, and iodine. Micro- Post measles diarrhea is particular- fections in nursing home residen-
nutrients have a relationship to an- ly difficult to treat and has a very ts. Vitamin D supplements may
tibody formation and the develop- high mortality. Vitamin A deficien- offer a cheap and effective immu-
ment of the immune system. The cy increases the risk of developing ne system boost against tubercu-
Copenhagen Consensus project respiratory disease and chronic losis. Vitamin D was used to treat
on hunger and malnutrition even ear infections. Vitamin A supple- tuberculosis in the pre antibiotic
suggested that efforts to provide vi- mentation sustains gut integrity, era, when special sanatoria were
tamin A, iron, iodine, and zinc ge- lowers the incidence of respiratory built in sunny locations, such as
the Swiss Alps. Investigators repor-
Table 1. Conditions of Under- and Overnutrition and Their Influence on Host Defense
Functions ted that a single 2.5-mg dose was
Deficiency Infections Response Mechanisms Infections sufficient to enhance the immune
Affected/Promoted
Acute PEM Phagocytosis, RNIs, ROIs, Opportunistic, respiratory, and system’s ability to withstand in-
antigen presentation, leukocyte intestinal infections, helminths,
extravasation, inflammation, T tuberculosis, measles, fection. These findings came from
cell activation, T cell memory, influenza, P. carinii a study that identified an extraor-
antibody titres (IgG, IgA),
cytokine secretion, leptin levels, dinarily high incidence of vitamin
macrophage activation
Chronic PEM Thymus development, T cell Respiratory and intestinal D deficiency among tuberculo-
differentiation, T cell infections, helminths, BCG, sis- susceptible women in Muslim
expansion, T cell memory, IgA, malaria, AIDS, measles,
IgG, complement and leptin influenza, skin infections, noma communities in London. Zinc is a
levels decreased, macrophage
activation trace mineral that is essential for
all species and is required for the
Vaccine efficacy BCG, encapsulated bacteria,
measles activities of 1300 enzymes, car-
Overnutrition Permanent preactivation of Opportunistic and fungal
leukocytes, IFN-γ/TNF-α infections bohydrate and energy metaboli-
increased, suppressed NK and T sm, protein synthesis and degra-
cell activation, reduced
phagocytosis, increased leptin dation, nucleic acid production,
concentrations often paired with
leptin resistance heme biosynthesis, and carbon
Diabetes Neutrophil, macrophage Tuberculosis, diseases due to dioxide transport. It is a cofactor in
functions (i.e., phagocytosis, opportunistic, multibacterial,
chemotaxis, extravasation), and fungal infections, the formation of enzymes and nu-
ROIs due to NADPH osteomyelitis, diabetic foot
consumption by polyol pathway (P.aeruginosa, Staphylococcus cleic acids and plays a critical role
aureus, S. pneumoniae, in the structure of cell membranes
Enterococcus)

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