Nutritional Pathology SCBM341: General Pathology

Transcription

1 Nutritional Pathology SCBM341: General Pathology Assistance Professor Amornrat N.Jensen, Ph.D. Department of Pathobiology School of Science, Mahidol University

2 Nutrients: Chemicals needed for growth and survival Essential nutrients : Cannot be synthesized by the body at all (or not enough) Non-essential nutrients : Can be synthesized by the body from food sources Macronutrients : Primary source and needed in large quantities : Carbohydrates, Proteins, Fats Micronutrients : Needed in relatively small quantities : Vitamins, Minerals

3 Adequate diet The diet must contain: 1. Energy - from carbohydrates, fats, and proteins 2. Amino acids and Fatty acids - building blocks for biosynthesis of proteins and lipids 3. Vitamins and Minerals - coenzymes, hormones, and structural components

4 Nutritional disorders Nutrition disorders are caused by nutritional imbalance An insufficient intake of food or nutrients OR An over-consumption of food or nutrients

5 Hypoalimentation/ Undernutrition Deficiency of one or more nutrients Results from various factors including: - Decreased dietary intake - Increased nutritional requirements - Impaired ability to absorb or utilize nutrients Modified from Assessment - Adult: Degree of weight loss - Children: Height and weight comparing with reference growth charts

6 Undernutrition Protein-energy malnutrition Vitamin deficiency Mineral deficiency

7 Protein-energy malnutrition (PEM) An energy deficient results from chronic deficiency of macronutrients Primary PEM - Caused by an inadequate nutrient intake Secondary PEM - Caused by disorders or drugs that interfere with nutrient use

8 Diagnosis of PEM Main parameter: comparison of the body weight for a given height with the standard Other parameters: - Skinfold thickness (indication for fat storage level) - Muscle mass (indication for somatic protein) - Serum proteins such as albumin and transferrin (indication for visceral protein)

9 Primary protein-energy malnutrition Results from an inadequate nutrient intake - No access to nutrients - Depression - Fasting - Anorexia nervosa malnutritionimprovement.blogspot.com

10 Two common forms of primary PEM in children 1) Marasmus - Decrease in somatic protein compartment 2) Kwashiorkor - Decrease in visceral protein compartment

11 Anorexia Nervosa an eating disorder that involves an inability to stay at the minimum body weight considered healthy for the person's age and height (PubMed Health) Person with anorexia nervosa will have an intense fear of gaining weight or becoming fat Symptoms also include 15% or below underweight and lack of menstrual cycles (in women)

12 Bulimia An illness in which a person binges on food or has regular episodes of significant overeating and feels a loss of control (PubMed Health) Person with bulimia will prevent weight gain by vomiting the food out, using laxative, or excessive exercise

13 Protein-energy malnutrition (PEM) An energy deficient results from chronic deficiency of macronutrients Primary PEM - Caused by an inadequate nutrient intake Secondary PEM - Caused by disorders or drugs that interfere with nutrient use

14 Secondary protein-energy malnutrition Commonly found in 1) Disorders that affect GI function 2) Chronically ill or hospitalized patients such as in patients with cancer or HIV 3) Conditions that increase metabolic demands Patients can have either marasmus-like or kwashiorkor-like syndromes

15 Undernutrition Protein-energy malnutrition Vitamin deficiency Mineral deficiency

16 Vitamin deficiency Vitamin A Vitamin D Vitamin E Vitamin K Thiamine Niacin Vitamin C Folate

17 Vitamin A deficiency The first sign of vitamin A deficiency is night blindness The retina of the eye needs retinol for low-light and color vision Vitamin A deficiency can lead to blindness by making the cornea very dry and damaging the retina and cornea

18 Vitamin D deficiency Vitamin deficiency can lead to rickets in children and osteomalacia in adults Rickets is a disease characterized by a failure of bone tissue to properly mineralize, resulting in soft bones and skeletal deformities Osteomalacia is the softening of the bones due to defective bone mineralization

19 Groups at risk for Vitamin D deficiency Breastfed infants Older adults People with limited sun exposure People with dark skin People with fat malabsorption pixmule.com

20 Vitamin E deficiency Depression Ataxia Loss of position and vibration sense Muscle weakness Impaired vision Impairment of the immune response

21 Vitamin K deficiency Dietary sources: mainly in green vegetables and some fruits Essential for production of prothrombin and other factors involved in blood clotting Regular diet usually provides sufficient amount of vitamin K Symptoms of vitamin K deficiency include heavy menstrual bleeding in women, anemia, bruising, and bleeding of the gums or nose

22 Thiamine (Vitamin B1) deficiency Nervous system and the heart are particularly sensitive to thiamine deficiency Thiamine deficiency lead to the following syndromes 1) Polyneuropathy (dry beriberi) - toedrop, footdrop, wristdrop 2) Cardiovascular syndrome (wet beriberi) - high-output cardiac failure, peripheral edema 3) Wernicke-Korsakoff syndrome - confusion, ataxia, vision changes, loss of memory, hallucination

23 Niacin (vitamin B3/ nicotinic acid) deficiency Niacin deficiency lead to the development of pellagra Symptoms of pellagra: 3D 1) Dermatitis 2) Diarrhea 3) Dementia Niacin can be synthesized in the body from tryptophan and thus having too less tryptophan can cause pellagra as well

24 Vitamin C (Ascorbic acid) Vitamin C cannot be synthesized in the body and so we have to receive it from food sources only Vitamin C plays a role in collagen synthesis as well as in free radicals protection

25 Vitamin C deficiency Vitamin C deficiency leads to the development of scurvy Hemorrhagic spots on the skin Spongy gums, loosing teeth Bleeding from the mucous membranes liveonearth.livejournal.com

26 Undernutrition Protein-energy malnutrition Vitamin deficiency Mineral deficiency

27 Mineral Chemical elements required by living organisms, other than carbon, hydrogen, nitrogen, and oxygen Zinc Iron Magnesium Chromium Selenium Manganese Molybdenum Copper Calcium Potassium Sodium Chlorine Phosphorus Iodine Hubpages.com

28 Mineral deficiency Major causes: Inadequate supplementation in preparations used for intravenous feeding Interfere in mineral absorption by other diet components Inborn defect in metabolism leading to abnormalities in mineral absorption

29 Zinc deficiency Zinc has a ubiquitous biological roles including metabolism of RNA and DNA, gene expression, signal transduction, etc. Example of zinc deficiency features: - Acrodermatitis enteropathica - Growth retardation in children - Impaired wound healing - Hypogonadism with infertility skory.choroby.biz.pl

30 Nutritional disorders Nutrition disorders are caused by nutritional imbalance An insufficient intake of food or nutrients OR An over-consumption of food or nutrients

31 Hyperalimentation Obesity Vitamin poisoning Mineral overload

32 Obesity A medical condition in which excess body fat has accumulated to the extent that it may have an adverse effect on health, leading to reduced life expectancy and/or increased health problems (wikipedia) Often use BMI (Body Mass Index), skinfold measurements, or body circumferences as a measurement for obesity. phsj.org

33 Body Mass Index (BMI) Overweight: BMI between 25 kg/m 2 and 30 kg/m 2 Obese: BMI greater than or equal to 30 kg/m 2

34 Causes of obesity Diet Lifestyle Genetics Medical illness Psychiatric illness

35 Obesity as a risk factor for chronic diseases Cardiovascular disease Diabetes High blood pressure Stroke Hypertriglyceridemia Sleep-breathing abnormalities bjty568.com Gallstones Some cancers e.g. colon cancer, breast cancer

36 Hyperalimentation Obesity Vitamin poisoning Mineral overload

37 Vitamin poisoning Toxic levels of vitamins are usually from high intake of supplement and not from dietary sources Example: Hypervitaminosis A - birth defects, painful joint, hair loss Hypervitaminosis D - hypercalcemia which can cause over-calcification of the bones, soft tissues, heart and kidneys Hypervitaminosis E - bleeding problems

38 Mineral overload Example: Iron overload Iron supplements Leading cause of fatal accidental poisonings among U.S. children under six years old Hereditary iron overload (hemochromatosis) Intestines absorb iron at a high rate despite the excess iron building up in body tissues Symptoms: Early symptoms: fatigue, mental depression, abdominal pain Late symptoms: liver failure, abnormal heartbeats, etc.

39 Nutritional disorders Nutrition disorders are caused by nutritional imbalance An insufficient intake of food or nutrients OR An over-consumption of food or nutrients

40 Suggested sources for reading Internet sources: U.S. National Library of Medicine, Wikipedia, Pubmed Basic Pathology Kumar, Abbas, Fausto, and Mitchell, 8th Edition, 2007 Pathologic basis of disease Robbins and Cotran, 8th Edition, 2010