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MALNUTRITION INFECTION AND DISEASEYOU ARE WHAT YOU EAT!!!!

Genesis 1 verse 29 “Then God said ,I have given you every herb & seed bearing plant in the face of the whole earth and

every tree that has fruit with seed in it. They will be yours for food.”

presented by

Dr E.G.C. Muchaneta-Kubara (Senior Lecturer)(HND Applied Biology UK, MSc Applied Immunology UK, PhD Nephrology UK)Dr P. Nziramasanga (Senior Lecturer) and Ms C. Berejena (Chief Tech)

Department of Medical MicrobiologyUZ- College of Health Sciences UNIVERSITY of ZIMBABWE

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ABSTRACT• Malnutrition is the condition that results from taking an

unbalanced diet in which certain nutrients are lacking , in excess (too high intake), or in the wrong proportions. A number of different nutritional disorders may arise depending on which nutrients are over or under abundant in the diet. In most of the world, malnutrition is present in the form of under nutrition, which is caused by a diet lacking adequate calories and protein.

• The World Health Organization cites malnutrition as the greatest single threat to the world’s public health. Improving nutrition is widely regarded as the most effective form of aid. Nutrition-specific interventions, which address the immediate cause of under nutrition , have proven to deliver among the best value for money of all development interventions.

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ABSTRACT (contd)

• Malnutrition is responsible, directly or indirectly for 54% of the 10.8million deaths per year in children under five years and contributes to every second death(53%) associated with infectious diseases among children under five years of age in developing countries. Infection causes energy loss on the part of the individual , which reduces productivity on the community level and perpetuates the alarming spiral of malnutrition, infection, disease and poverty.

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BARRIER DEFENSES

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Background:THE IMMUNE SYSTEM

• Immune system protects body against infection and disease • It is a complex network of cells and organs defending the body against

pathogenic organisms and the development of cancer. It is divided into two parts – Innate and Adaptive System.

• Innate is an immediate nonspecific response to harmful substances (first line defense against invading pathogens)

• Composed of physical barriers such as skin and chemical and microbiological barriers including mucuos secretions in respiratory/genital tract and normal microflora of the gut

• Primary components include monocytes, macrophages, and neutrophilis involved in phagocytosis

• Complement directly kills bacteria (composed of 20 serum proteins) found in the blood

• Any breach of the barrier defense will ultimately result in disease

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INNATE IMMUNE SYSTEM

• When innate system fails to eliminate invading microorganism and resulting infection then adaptive immune response is summoned via messenger proteins called cytokines

• Key component is the complement classical and alternative pathway which is a biochemical cascade of at least 20 serum proteins

• Complement kills invading pathogens by direct lysis (cell rupture) or promotion of phagocytosis

• Complement proteins float freely in blood, and help to destroy pathogens (change the surface of bacteria)

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Adaptive(acquired) immune system

• Develops over a long period several days or weeks• More complex involving antigen- specific responses and

immunologic “memory” (vaccination, immunization)• Subsequent responses to same antigen are stronger and

more efficient• Major mediators are specialized white cells (T and B

lymphocytes)• T-cell responsible for cell –mediated immunity • B-cell responsible for humoral immunity (antibody)• Innate and adaptive immune responses interact to protect

the body from infection and disease

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Immune system and Nutritional Status

• Ability of the immune system to prevent infection and disease depends on nutritional status of host

• Poor overall nutrition can lead to inadequate intake of energy and macronutrients as well as selected micronutrients

• Deficiencies can cause immuno-suppression and dysregulation of immune responses

• Can impair phagocyte function (innate) cytokine production (acquired) as well as adversely affecting aspects of humoral and cell-mediated immunity

• Can compromise the integrity of immune system thus increasing susceptibility to infection

• Nutritional status can modulate actions of immune system

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Nutrition and Immunology• Protein-energy malnutrition (PEM) is the most common

nutritional problem• Causes are insufficient intake of protein or energy (developing

world)• Industrialized nations PEM is due to chronic disease in certain

subgroups, elderly and those hospitalized interferes with nutrient metabolism in diseases such as inflammatory bowel, chronic renal failure and cancer

• PEM affects cell-mediated immunity (thymus atrophy) )• Affects the number of circulating T cells and decreases

responsiveness of the memory cells to antigen (opportunistic infections)

YOU ARE WHAT YOU EAT !!!FOOD SECURITY• Ability to have food all year roundSupport a healthy life style- accessibility of food supply•Availability –purchase adequate amountsKnowledge of how to utilize the food effectively (disease absorption) •Policy– conducive polices, environmental conditions.

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Malnutrition

• Lack of nutritional elements necessary for human health

• Nutrient deficient foods• Poor dietary practices• Diseases that prevent body from absorption

of nutrients• Education and capacity building are key

components

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Nutrition and Immunology

• Humoral antibody affinity and response is decreased also reduction of cytokines ,several complement proteins and phagocyte dysfunction

• Secondary PEM is common in developed countries• PEM compromises the integrity of mucosal barriers

increasing susceptibility to respiratory , gastrointestinal and urinary tract infections

• PEM occurs in combination with deficiencies in essential micronutrients Vitamin A, zinc, copper, selenium and magnesium

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Poverty

Severe or frequent infections: Diarrhoea, Pneumonia

Insufficient supply of protein, energy or micronutrient

Insufficient child maternal care

Little education of women

Insufficient household food

security

Unhealthy environment

Malfunctioning of society Injustices War, Natural disaster

MALNUTRITIONModerate, severe (Marasmus-Kwashiorkor

Micronutrients deficiencies

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The Malnutrition-Infection Complex

• Can be viewed under two aspects;• Malnutrition compromises host defense, infection can aggravate

a previous existing deficient malnutrition state triggering malnutrition through disease pathogenesis

• Malnutrition facilitates pathogen invasion and propagation• A consequence of health issues such as gastroenteritis, chronic

illness especially HIV/AIDS pandemic, and/ diabetes• Diarrhea and other infections can cause decreased nutrient

absorption and intake of food, increased metabolic requirements and direct nutrient loss

• Parasite infection also causes malnutrition such as in giardiasis (Giardia lamblia) and helminthic infections

Water

• Link between water , sanitation an health are well understood in Zimbabwe following 2008 cholera outbreak and recurrent episodes of typhoid/cholera to quality of life both urban and rural.

• It is a nutrient food and non food resource essential for daily living

• Access to water may affect nutrition• African women walk long distances to fetch water

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Sanitation

• Over 48% of population defeacate in the open• Microorganisms in faeces can contaminate

into food or water• Construction of latrines can hide faeces from

flies• Improved hygiene will cut off faecal

contamination- reducing transmission routes • Promoting a culture of healthy communities

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The Malnutrition-infection Complex

• Haemophilus influenza type b – mostly an opportunistic infection pathogen causing invasive infections e.g. pneumonia in children under 5 years.

• Can increase probability of a secondary infection• Can modify disease pathogenesis and prognosis• There is a relationship between malnutrition immune suppression and

infection complex• Infection can contribute to malnutrition; in gastrointestinal infection leading

to diarrhea, or chronic infections that cause cachexia and anaemia, intestinal parasites (hookworms, malaria) can cause anaemia and nutrient deprivation (protozoa and helminth)

• Despite availability of antibiotics mortality and morbidity rates remain high especially in malnourished children below 24 months.

• Pneumonia and malnutrition are two of the biggest killers in childhood disease

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The Malnutrition-Infection Complex Contd

• Acute diarrhea and pneumonia occur frequently in first 2-3 years of life

• In these immuno-competence is impaired when first exposed to pathogens

• Infection can suppress appetite and this directly affects nutrient metabolism

• These events lead to poor nutrient utilization • Streptococcus pneumonia leading cause of bacterial pneumonia,

meningitis and sepsis in children worldwide.• Pneumococcal disease precede by asymptomatic nasopharyngeal

colonization especially high in children• This is natural route of infection of S.pneumoniae - may progress to

invasive diseases if immunological barriers are crossed.

Infection

• Metabolic effects of infectious process are accompanied by a significant reduction in food intake

• Due to anorexia and most cultures restrict food intake to the sick ( children)

• Nutrient loss due to diarrhea and ↑ energy loss due to fear will aggravate the already unfavourable condition

• Malnutrition makes the infection worse due to unhealthy micosal surfaces – which allow early introduction of microorganisms

• Also poor immune system permits rapid multiplication of invading microoganisms

• Recovery is slow and less available to repair damaged tissue 19

Diarrhoea

• Affects nutritional status in child by losing appetite

• Associated vomiting• Severe dietary restriction and mal-absorption• result in weight loss and malnutrition• Diarrhea is both cause and an effect of

malnutrition

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Relationship Between Malnutrition and Infection

• Field studies have shown that relationship is bidirectional• Site of interaction and type of pathogen determines the type

of immune response• Initiation of both innate and adaptive responses involve

activation and proliferation of immune cells• There is synthesis of an array of cells, associated DNA

replication, RNA expression and protein synthesis which all consume anabolic energy

• Nutritional status of host determines the outcome of resulting infection

• Poor overall nutrition can lead to nutritional deficiencies

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Relationship between Malnutrition & Infection

Infection

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Measurement of Growth/Repair (Serum levels (ng/ml) of Insulin-like growth factor-1 (IGF-1))

• IGF-1 increases protein synthesis and suppresses protein degradation• It is a mediator of growth hormone effects and circulates in blood bound

to binding protein 3• Important effects on muscle metabolism through stimulation of amino

acid and glucose transport• Fasting causes a decline in serum IGF-1 and hepatic mRNA, re-feeding

reverses this• Routine assessment of nutritional status employ anthropometric

measurements• Cannot be done retrospectively• The simple IGF-1 Elisa assay can be used to assess accurately large sample

numbers• IGF-1 is a nutritional status marker that can be used in monitoring and

measuring the impact of a particular dietary manipulation

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Malnutrition and Infection

• In malnourished children a greater proportion suffer from bacterial GI and respiratory infections

• In these types of infection the first line defense is innate epithelial barriers and the mucosal immune response

• PEM greatly compromises these responses vitamin A deficiencies induces loss of mucus producing cells which increases susceptibility to infection by pathogens ordinarily trapped

• The barrier defects are critical in the pathogenesis of respiratory and GI infections

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Malnutrition and Infection Contd

• Upper respiratory infection most prevalent in children with acute malnutrition. Lower respiratory infection most prevalent in acute/chronic malnutrition. (Cherish et al).

• The group studied moderate – severe degrees of malnutrition and found out that these increases mortality risk. Pneumonia is more common among children with Marasmic Kwashiokor than other types of malnourishment.

• Klebsiella species and Staphylococcus aureus were most common causative aspects in severely malnourished children.

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Malnutrition and Infection Contd• Also pathogenic viruses isolated from malnourished children with

pneumonia. Mycobacterium tuberculosis also detected in malnourished children with pneumonia.

• Role unclear – present in acute lower respiratory infection in severely malnourished children.

• In absence of organized effective immune response antibiotic alone incapable of eliminating bacterial pathogens innate response provides 1st line of defense against infection estimates that 98% protection.

• Effective respiratory host defense depends on specific Abs, complement, neutrophils and other phagocytic cells.

• If pathogens overcome these – and given entrance into blood stream, systemic protection mediated by anti capsular antibodies – reduced mucosal immune response might lead to persistent and reccurrent colonization and subsequence infection.

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“YOU ARE WHAT YOU EAT”

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WHAT IS A BALANCED DIET?ESSENTIAL MINERALS and VITAMINS

• Best place to find vitamins and minerals (anti-oxidant role) is food and together contribute to many body functions

• Needed by the body as trace small amounts (micro nutrients) or macro (large amounts)

• Prevent damage to tissues and cells by electrons (free radicals) generated as by-product of inflammation and other body functions

• Supplements should be taken with food for absorption• Temporal fluctuations as a result of viral infection

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ESSENTIAL MINERALS

• Calcium most abundant in the body needed for developing and maintaining healthy bones and teeth

• Requires the presence of phosphorous, magnesium, vitamin D and K for adequate absorption

• Deficit contributes to osteoporosis, hypertension, elevated cholesterol and rickets

• Dietary source: cheese, milk, yogurt, almonds, dark leafy green vegetables, broccoli, oysters and sardines

• Many foods are fortified with calcium such soy milk, juices and cereals

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Essential Minerals

• Chloride electrolyte works together sodium, potassium and carbon dioxide to maintain acid balance of body fluids

• Increased levels may suggest dehydration or alkalosis• Low levels : may be a result of Addison disease, congestive

heart failure or vomiting• Dietary sources: salt, sea salt, tomatoes, celery, olives and

seaweed• Dietary requirement according to age, sex and health status

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Essential Minerals

• Magnesium necessary for bone and teeth formation• Normal function of nerves and muscles• Enzyme to work properly• Deficiency may cause sleepiness, muscle spasms, nausea and

seizures• Too much : low blood pressure, difficult breathing and cardiac

arrest• Dietary source halibut, white beans, oat bran, spinach ,

cashew and brazil nuts

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Essential Minerals

• Potassium active in muscle and nerve communication• Moving nutrients into cells and waste out of cells• Deficiencies may arise from Addison’s disease kidney failure

and blood transfusion where the levels are high• Low levels include Cushing syndrome, chronic diarrhea,

vomiting and diuretics• Dietary sources: bananas, pears, peaches, grapes, kiwi,

watermelon, tomatoes, pumpkin, sweet potato(skin) green beans and carrots

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Essential Minerals

• Phosphorous second most abundant mineral in the body

• Helps build strong teeth and bones• Filters waste in kidneys• Helps body to store and use energy• Active role in tissue ands cell growth and milk and • repair• Dietary source: milk and meats• Adequate calcium and protein will provide enough

phosphorus (zviyo)

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Essential Vitamins- Organic food substances in plants/animals

• Vitamin A (beta-carotene)converted in the body when needed • Maintains the integrity of barrier defenses and is increased vulnerability to respiratory and

diarrheal diseases• Protects against flu and infections of the kidneys , bladder, mucous membranes, counteracts

night blindness and builds resistance to infection• Derivative retinoic acid functions as hormone to 500 genes several of which are involved in

controlling, production, proliferation and differentiation of immune cells• Stabilizes CD4 counts in HIV positive individuals• Deficiency affects cell-mediated immunity and antibody response to antigen • A common deficiency worldwide especially developing countries• Has detrimental effects on maternal and child health• Severe deficiency in children increases morbidity and mortality related to measles, malaria

and diarrheal infections • Loss of appetite, frequent fatigue, retarded growth and defective teeth and gums• Dietary source: coloured yellow, red orange vegetables and fruits including carrots,

tomatoes, apricots and sweet potato • Papaya rich in carotene (good for eye sight)

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Essential Vitamins• Vitamin B1(thiamin) is essential in the formation and

maintanance of muscle• Protects the body from • Efficient use of carbohydrates as energy• Required during feverish conditions• Dietary source ; whole grain, whole-meal bread, brown rice and

pulses • Vitamin B2(riboflavin) is the building block for glutathione a key

cancer fighting anti-oxidant • Deficiency symptoms include cracking at the corner of lips/mouth• Dietary sources : dairy products, leafy vegetables, fruits -

watermelon, meat and cereals

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Essential Vitamins

• Vitamin B6 (pyridoxine) is involved in the formation of new cells and maintaining immunity

• Can reduce the toxicity of TB drugs• Reduce the risk of heart attack• It is suggested that the use of ARV increases

the need for this vitamin• Dietary source; wheat germ and walnuts good

source of B vitamins, bananas, avocado pears

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Essential Vitamins• Vitamin B12 protects against nerve damage and neutropenia

disorders• If injected in (toe) HIV patients improves mental functioning• Supplementation (months) improves mental function• Reduce risk of neutropenia and anaemia following ARN treatment • Deficiency of B12 before treatment prone to neutropenia/anaemia • Absorption of this vitamin is poor if gastro intestinal problems present• All vitamin B operate in combination and in conjunction with each

other and minerals • Dietary source fish ,eggs dairy products if supplementing take as

vitamin B complex

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Essential Vitamins

• Vitamin C : can prevent HIV from infecting new cells, activation or replication of HIV in dormant infected cells

• Potent anti-viral – required by immune cells which fight bacteria and fungal infections

• High levels assist phagocytes in identifying and destroying candida species

• Dietary source: kiwi fruit ,orange, apple, guava, papaya• High doses cause diarrhea, kidney stones due to excess

acidity (use oxalic excretion testing urine)• More serious effect intravenous in people with glucose-6-

phosphate dehydrogenase deficiency

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“YOU ARE WHAT YOU EAT”

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LET US CHOOSE WHAT WE EAT AND LIVE LONG

• Hosea 4 verse 6 My people perish because of lack of knowledge because you have rejected knowledge I ALSO REJECT YOU AS MY PRIEST because you have ignored the law of your God I WILL ALSO IGNORE YOUR CHILDREN

•EAT FRUIT ON AN EMPTY STOMACH

• DRINKING COLD WATER AFTER A FATTY MEAL CAUSES CANCER• REDUCE SALT INTAKE- Replace with herbs rosemary, thyme,

marjoram, sage • DRINK NATURAL fruits and vegetables use blender or

pestle/mortar

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Nutrition and Immunology

• MALNUTRITION – INFECTION COMPLEX• Increases probability of a secondary infection• Compromises host defense• Facilitates pathogen invasion and propagation in chronic

illness such as HIV and AIDS• Diarrhoea decreases nutrient intake• Infection can suppress appetite • Nutrient loss related to poor nutritional utilization• Barrier defense critical in the defense of respiratory and GI

infections

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Adaptive(acquired) immune system

• NUTRITION AND IMMUNITY

• PEM – most severe?? Insufficient intake of protein• Chronic disease• Elderly hospitalized• Interferes with nutrition metabolism (chronic renal failure and cancer)• Affects cell mediated immunity (circulating Tcells decrease

responsiveness of memory to antigen)• Increases susceptibility to respiratory, gastro and urinary tract infection• Occurs in combination with deficiencies in Vitamin A, Zinc, Copper,

Selenium and Magnesium

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CONCLUSION

• Malnutrition major intervention is at risk in community based/health care• Nutritional supplements are concentrated sources of nutrients with expected

nutritional/physiological benefits• May be used to correct nutritional deficiencies and maintains an adequate intake of

given nutrients• Atnut – Catholic Relief Services also in Zimbabwe – lack of evidence on impact• Corn Soya Blends – protein source for targeted groups. Fortified with vitamins and

minerals• Plumpy nut – peanut based paste – administered at home enriched with vitamins

and minerals• Advocating natural traditional foods – 9 nutripack as a supplement – available locally

and sustainable• Zimbabwe experiencing major burden of malnutrition and working with several

NGOs• Need to evaluate a Nutripack – name given and accessible for sustainable assistance.

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REFERENCES

• Bonn 2011: No food and Nutrition Security without Water , sanitation and Hygiene, Nexus Conference, Hot Topic Session 7, Issue Paper, Convener German WASH Network.

• Briend A, et al (22 May 1999). The Lancet Volume 253, Issue 9166. Ready to use therapeutic food for treatment of marasmus, pages 1767 -1768

• Biesel, W.R. (1996). Nutrition and immune function: an overview. Journal of Nutrition, 126 (suppl); 2611S-2615S

• Chandra, R.K. and Kumari, S. (1994). Effects of nutrition on the immune system. Nutrition, 207-210

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YOU ARE WHAT YOU EAT!!!!!

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THANK YOU