. . Theme of the lecture““Peculiarities of

Carbohydrate and Lipid

Metabolism in Childhood Age,

Semiotics of Disturbances” ”

Chair of Children’s Surgery and Propedeutics of Pediatrics

Plan of the lecture

The role of carbohydrate metabolism in the general metabolism.Peculiarities of carbohydrate metabolism in children.Semiotics of carbohydrate metabolism disturbances in children.-The role of fat metabolism in the general exchange of substances .Peculiarities of fat metabolism in children.Semiotics of fats metabolism in children.

Carbohydrates are divided into 3 large groups: mono-, oligo-, polysaccharides

Function of carbohydrates in the organism:Glucose - the main source of energy for the

development of fetus, and is the only deliverer of energy for the cells of the brain and erythrocytes. Insufficient amount of carbohydrates inhibits fats metabolism (“fats burn in the flame of carbohydrates”).

Carbohydrates are in the structural elements of the cells in the form of gly coproteids and lipopolysaccharides, in the contents of biological elements (enzymes, hormones, immune cells), in the form of mucopolysaccharides – in the connective tissue.

Carbohydrates regulate digestion. They are divided in 2 groups: those assimilated in the human organism and those not assimilated. (oligo- and polysaccharides, coming into the tissues, regulate digestion). The need in carbohydrates – 10-12g/kg in breast feeding age, 14-15g/kg in children of the older age groups. In the mother’s milk the main carbohydrate is lactose, which promotes the growth of bifidoflora. It does not cause fermentation processes in intestines, is better assimilated.

Peculiarities of carbohydrate metabolism in children

Carbohydrate metabolism in fetus depends on the nutrition of a pregnant women. Violation of proportion insulin/glucose in a pregnant women because of wrong nutrition leads to disturbances of carbohydrate metabolism in a child.In new born children high activity of carbohydrates burning -by 30-35 % -is higher than in adults.After the birth the amount of glucose in the blood decreases in 4-6 hours. Reaches the minimal size and in 10-14 hours obtains the age norm. Premature children have insufficient glycogen. In general, for early age babies insufficient glycogen synthesizing ability of the liver is characteristic and also quick exhaustion of carbohydrates reserves takes place.

Digestion of carbohydrates

The start is in the oral cavity, where from the mucous glands amylase is discharged, which is inactive up to 3 months. In the stomach digestion of amylase by mucus is going on. Mostly are digested carbohydrates (hydrolysis) in small intestine (proximal portion) under the action of delta-amylase of pancreas, where they are splitted into mono- (glucose, galactose) and disaccharides.

Disaccharidase transforms disaccharides into monosaccharides , which are able to be absorbed.The main hormone, holding the level of sugar in the organism and regulating its metabolism is adrenalin (increases the level of glucose) and insulin (decreases the level of glucose).

Synthesis of reserve carbohydrate – glycogen

Takes place with the help of a number of enzymes, when necessary, glycogen is splitted into glucose. A process of glycogen formation in fetus and adult person is identical, but there are differences in the activity.In the last 2-3 months of intra-uterine development there is active process of glycogen synthesis, which in the first days of the child is splitted for energy supply of the organism. Its synthesis in the first 2-3 months is almost absent. The glycogen contents in the last weeks of pregnancy reaches 10% of the mass of the organ, during the first day – 1%.

Diabetes mellitusDM – a disease caused by absolutely or relatively insulin insufficiency, accompanied with violation of metabolism of proteins, fats and carbohydrates and gradual disturbances in all organs and systems.

Clinical signs of diabetes mellitusDryness in the mouth, thirst;Polyuria;polydipsia;thinning;itching and purulent spots on the skin;Atrophy of the muscles and osteoporosis.

Complications:myocardial dystrophy;diabetic nephroangiopathy;retinopathy;fatty infiltration of the liver, cholestasis.

Differential diagnosis of hyperglycemia and hypoglycemia

  Clinical signs Hyperglycemia Hypoglycemia

Skin and mucous membranes

dry, turgor decreased  skin is wet, turgor saved

Muscular tone low increased, convulsions

Complaints loss of appetite, vomiting, nausea, weakness, apathy, inhibition

Severe hunger, feeling of fear, anxiety

Pains in the abdomen often severe no

ACT decreased normal or increased

Aceton smell from the mouth

there is no

Disturbed urination polacuria no

Lactase insufficiency (LI)LI is insufficient activity of intestinal lactase (disaccharidase, which splits lactase sugar).Primary LI – congenital defect of enzyme system. Secondary LI – at a back ground of diseases (for example, intestinal infection), constitutional.LI in premature and small weight children is transitory and connected with morphofunctional immaturity.

Clinical manifestation of LI thin stool with sour smell;abdominal pains;meteorism, flatulence in abdomen;noises in the abdomen;milk taking symptoms;In clinical picture there can be only definite symptoms, but their appearance always is connected with taking milk.

Laboratory diagnostics of LIdetermining carbohydrates in the stools without idendification;method with lactose exertion;determination of CO2 in the air around;undigested lactose serves a substrate for bacterial activity, producing carbonic acid. In LI concentration of carbon dioxide is increased.

Treatment of lactose

insufficiency 

• unlactose diet, excluding milk, in some cases excluding of sour milk products (butter, cheese is permitted);• breast fed babies are put on nonlactose or low lactose milk mixtures;• a medicine Kerulac (Yamanuchi Europe, Japan). Adding some drops to breast or cow milk with the following incubation for 2-3 hours gives non lactose product.

Galactosemia – a disease, connected with disability of lactose absorption by the organism.

Pathogenesis:deficit of galactose-1-phosphaturidiltransferase;disturbed transformation of galactoso-1-phosphate into glucose-1-

phosphate.Semiotics:

the first signs appear just after the child is born;hepatomegalia;vomiting, anorexia, aminoaciduria;hypotrophy;delay of intellectual development;sometime hemolytic anemia is diagnosed;in the urine there is galactose and galactose-1-phosphate.

Glycogenoses glycogenoses are genetically determined diseases of accumulation, in the basis – deficit of enzymes, taking part in glycogen metabolism.

The disease of Girke – insufficient glucose-6-phosphate. Characterized with :

hepatomegalia, convulsions, coma, ketosis;disproportion of the body (large abdomen and

head, short extremities);frequent hypoglycemias.

Pompe disease – insufficient of acidous lysosomal a-1,4-glucosidase. Glycogen structure is normal, but there is no possibility of its splitting. Clinical characteristics:appears just after the child is born;hepato- and cardiomegalia;muscular hypotonia;cardiac insufficiency develops, which leads to death.

  

Biological role of fats in the organism

  Fats are of high energetic value (1g-9 kcal);are in the contents of:nervous system cells membranes;cellular membranes of all organs and systems; take part in: synthesis of adrenal hormones and prostaglandins;defense of the organism for excessive hit discharge;transport of fat dissolving vitamins.

Biological role of fats in the organism

Fats are complicated fermentative complexes, taking part in:immunologic reactions;processes of digestion;blood coagulation.

Peculiarities of fats metabolism in children

Accumulation of fat in fetus takes place in the last months of pregnancy. - after the 25th week. In the 11th week of pregnancy in the organism of fetus there is about 2 % of fat. In 33 weeks – 6,5 %, in the organism of mature child – 12-16%.In 6 months in the child’s organism there is 26% of fat of the body mass. At this age half of a day calories is covered by fat. Further on the fat weight is decreasing and the lowest is in prepubertal age.With the beginning of sexual maturity the amount of fat is growing again and: in girls –higher than in boys.

Peculiarities of fat metabolism in children

Fats, unlike of glycogen, do not go through placenta, they are synthesized in the fetus .

Level of cholesterol:in the mother’s blood – 7,9 mmol/l (305mg%);in umbilical blood- 6,7 mmol/l (260 mg%);in the blood of a new born – 2,8 mmol/l (110mg%).

After the birth the structure of fat and chemical composition is changed: fatty tissue of a new born child contains 56% of water and 35% lipids, in an adult – the contents of lipids is 71,7%, water – 26,35. In a new born child fat contains more saturated acids than in older age children:Fatty acids:

palmitin acid: in new borns – 29%; in adults - 8 %;Olein acid in new borns - 69%; in adults - 90%.

Lipidogram of children’s blood has its peculiarities. The contents of general lipids in the blood increases, only in the first year it increases 3 times. Need in lipids - 8-6g/kg/day (8g/l – in children of the 1st half a year).

Age peculiarities of lipid content and its fractions in children

Indices 1 hour 6-10 days 1-2 months 2-14 years

General lipids, g/l

Triglycerids, mmol/l

Cholesterol, mmol/l

Unsaturated acids,mmol/l

Phospholipids, mmol/l

Lecitin, g/l

2

0,2

1,3

2,2

0,65

0,54

4,7

0,6

2,6

1,2

1,04

0,8

5

0,39

3,38

0,8

1,6

1,25

6,2

0,93

5,12

0,45

2,26

1,5

Lipid metabolism violation Disturbances in lipid metabolism can take place in different stages of metabolism. There hereditary genetic defects and diseases, acquired during life. Violation of lipid digestion and absorption can be:blocking of biliary ducts of various etiology;hypersecretion of saline acid, which inactivates the pancreatic acid;in pathology of digestive tract;in violation of lipid metabolism in the stool appears fat –steatorrhea

ObesityThe main features of the growing organism, don’t give the development of obesity. The child’s organism loses very much energy, connected with motor activity, processes of growth and development, large surface of the body on a unit of mass, and so high heat loss.If, in spite of this peculiarity of the child’s organism, obesity develops, this is an indication of serious violation of neuro-endocrine regulation of the activity of the inner organs, and also metabolism and indicates considerable difficulties in elimination of pathological process.

Obesity in the childhood age has often unfavourable prognosis: in modern conditions there are many stout children who carry the “load of fat” all the life. Obesity is expressed in the constitution of a person, leads to changes in the whole organism, the organs and systems, has negative action on the psychic development of a child.

ObesityObesityCalculation of IBM - Index, Body, Mass.IBM is calculated with a formula: IBM= m/h in quadrant , where m – mass of the body(kg), h – height (m); There are such measures of the IBM: less 15 –acute deficiency of mass; from 15 to 20- deficit of mass; from 20 to 25- normal mass; from 25 to 30- excessive weight , more than 30 - obesity.

There are 2 types of obesity – hypercellulary and hypertrophic

Hypercellular (multicellular, hyperplastic) obesity is every case of stoutness with increase of the amount of fat cells in the organism. The sizes of the cells may be large or normal.

Hypertrophic type of obesity is characterized by normal number of fat cells and their large sizes. The first type takes place in children, the second type develops in adult person.

10 reasons of excessive weight in children

1 Overfeeding, the parents give too much food to their “dear baby.” 2 Sweet food. Overeating of sweets gives more energy, the baby cannot spend all of it, and fat is accumulated on the body.3 Gaseous drinks and sweet juices.

44 Consequences of advertisements and bad education. 5 Stresses and fears. In these cases the children seek something in refrigerator. Eating inhibits the fears and stresses.6 Not sleeping enough. The organism tries to make a stress state milder with eating tasty sweet or fatty food.7 Automobils. The parents take the child to school, to the forest and other places, not giving them to move more actively.

8 TV or computer. They are enemy number 1 for family fight for slenderness.9 Genetic factors. If the parents are stout, there is a theme for thinking. Such parents must try to do something with nutrition regime of their child. 10 And only the 10th reason has medical basis - it is violation of endocrine system.

ObesityIn children more frequently are met 2 types:

Alimentary-constitutional (75-97%) and neuro-endocrine (hypothalamic) obesity.

Hypothalamic obesity develops after infection, intoxication, cerebro-cranial traumas, labor traumas, weak septic processes, encephalitis, disorders of CNS (adenoma of hypophysis, hemorrhage, cysts, etc.).

The plan of examination of patients with obesity at a background of endocrine

disturbances Hormonal investigation:for diagnosing hypothyrosis: determination of the level of TTG, in its change-free T4;If there is sexual maturity- FCG, LG, prolactinestradiol, testosterone, examination according to the corresponding protocol;In the signs of hypercorticysm – examination according to a special protocol;The level of leptin and insulin in the blood;In the symptoms of pseudohypoparathyrosis – determining the level of calcium, phosphorus, parathormone in the blood;  

Diet in obesity

 Lightly absorbing carbohydrates, sugar, sweet gaseous drinks, sweets are excluded, as well as fatty fish, macaroni, concentrated juices, etc.In strict diet cereals, potatoes, bread, sour cream, ice-cream are excluded.

Pathogenesis of congenital disturbances of lipid metabolism:

Violation of the structure or function of enzyme or protein, transporting metabolites through the cellular membrane;Over accumulation of toxic metabolites;Deficit of substances, necessary for normal metabolism.

Clinical manifestation of congenital disturbances in lipid

metabolism

Recurrent attacks of vomiting;Acidosis;Strange smell of urine or sweat;Hepatosplenomegaly;Delay in growth;Delay in mental development;Megaencephaly or atrophy of the brain,

Convulsions of unknown origin;Episodes of loss of consciousness, changing into coma; In the family anamnesis deaths of children in early age;Hyperamoniemia.

The main syndromes in lipid metabolism disorders

Sheldon syndrome – a syndrome of fat malabsorption, caused by the absence of pancreatic lipase.

Signs:celiac like syndrome (diarrhea, steatorrhea, hypotrophy);stroma and erythrocyte membranes are disturbed;slow rise of body mass is observed.

AbetalipoproteinemiaIt is absence of B-lipoproteins of low integrity, and disturbed fat transportation as a result.celiac like syndrome (diarrhea, steatorrhea, hypotrophy);the blood serum is transparent;lipid content in serum is low;decreased content of cholesterol, phospholipids, triglicerids in plasma;pigmental degeneration of retina;demielinization of cerebellum and oblique trunks of the spinal cord;cerebellar ataxia.

Glycolipidosis – disturbance in glycolipids disintegration processes

Goshe disease –loss of activity of glycocerebrosidase, as a result – accumulation of glycocerebroside in the cells of RES. The main symptoms: frequent nasal bleedings; skin hemorrhagic eruptions;intense uterine bleedings ;lagging in development, infantilism, stop in the growth.hepatosplenomegaly, pains in tubular bones while moving;hyperpigmentation of the skin of the hands, the face, hypersplenism, anemia.

Goshe disease

Goshe disease

Cells of Goshe The liver in Goshe disease

Hyperlipoproteinemia – frequent genetic disease

There are 5 types of hyperlipoproteinemias depending on the content of fat fractions.Clinical manifestation:xanthomes on palms, on the buttocks, in periorbital area;signs of pancreatitis;retinopathy;the early development of atherosclerosis;high content of cholesterol;hepatomegaly.

Tay-Sachs disease(early children’s amavrotic idiocy)

The disease had been called on the names of Brittish ophthalmologist Warren Tay (1843-1927) and American neurologist Bernard Sachs (1858-1944).This is disturbance in gangliosides metabolism, accompanied by their localization in the gray cells of the brain, the liver, the spleen. Clinical picture: psychic disturbances are progressing; degeneration of intellect is observed, disturbed eye sight and hearing(blindness, deafness), muscular hypotonia, paralysis of extremities, tonic convulsions.

Tay-Sachs disease There are 2 kinds of the disease:The 1st – early –develops just from the moment of the child is born, and the life duration of the child in this case is 4-5 years.With the late development- appears between the period of sexual maturity and 23-26 years of age. The life duration depends on the graveness of symptoms. Such patients can live normal life time, like all healthy people.

The eye fundus under the disease of Tay-Sachs

(the spot of dark-red colour) 

The disease of Niman-Picke (sphingomyelinlipoidosis)

• The disease develops as a result of accumulation in the cells of reticuloendothelium of phospholipid-sphingomyeline as a result of loss of activity of sphingomyelinase enzyme.• Clinical picture: lagging in psychomotor development, progressing hepatosplenomegaly, neurologic disturbances (spastic tetraparesis, blindness, deafness). The skin takes a brownish colour.Treatment - symptomatic, of low effectiveness • Frequency - 1 in 10000 children. Is met only in early childhood age and is characterized with malignant course.

The disease of Niman-Picke