Lecture The digestive system in children

1. Morpho-functional Peculiarities
of the Digestive System in Children.
Methods of an examination.
Semiology of diseases.
Chief of Department of Propedeutic of Pediatrics N2
Kharkiv National Medical University
Klymenko Victoria Anatoliivna
Kharkiv National Medical University

2. Contents
 Embryogenesis of the digestive system.
 Morphofunctional peculiarities of organs of the digestive
system in children.
 The main clinical methods of investigation of the digestive
system.
 The main paraclinical methods of investigation.
 Semiotics of diseases of organs of the digestive system.
Main pathological syndromes.

3. Embryogenesis of the digestive system
Originates from endoderm
7-8th days – primary intestine
12th day – division into two parts:
1. Intraembryonal (future digestive tract)
2. Extraembryonal (yolk sack)
4th week – differentiation primary intestine
into 3 parts:
1. Foregut
2. Midgut
3. Hindgut

4. Embryogenesis of gastrointestinal system
Three parts of the primary intestine (foregut, midgut and hindgut)
are formed by the end of the 4th week of gestation.
parts of the
duodenum and
the small intestine
large intestine
The liver,
pancreas, and
spleen
develop from a
specialized
layer of the
fore- and
midgut.

5. Foregut Derivatives
 Oropharyngeal membrane (cranial end)
 Pharynx (derivatives of the pharyngeal pouches, tongue, thyroid gland)
 Thoracic esophagus (lung buds)
 Abdominal esophagus
 Stomach
 Cranial half of duodenum (liver, gallbladder, pancreas)
 Caudal end = Ampulla of Vater (common bile and pancreatic ducts drain)

6. Cleft palate
Worldwide, oral clefts
in any form (i.e., cleft
lip, cleft lip and palate,
or isolated cleft
palate) occur in about
one in every 700 live
births (WHO, 2001)

7. Anomalies - Foregut
 Esophageal
stenosis (narrowing)
– abnormal
recanalization
 Esophageal atresia
(abnormal opening)
 Trachea-esophagus
fistula

8. Anomalies - Foregut
Stomach
Pyloric stenosis –
hypertrophy of smooth
muscle, projectile
vomiting

9. Anomalies - Foregut
Pancreas:
 Annular pancreas – Pancreatic tissue
encircling the duodenum sometimes
causing obstruction
 Heterotopic pancreatic tissue -
Misplaced pancreatic cells
Liver:
 Biliary atresia – abnormal hepatic duct
formation – varying severity postnatal jaundice

10. Midgut derivatives
 Caudal half of duodenum
 Jejunum
 Ileum
 Cecum
 Appendix
 Ascending colon
 Right 2/3 of transverse colon

11. Herniation and rotation
of the midgut into the umbilical cord
6th – 10th weeks
of gestation

12. Anomalies - Midgut
 Duodenal stenosis and atresia – abnormal
recanalization
 Omphalocele - failure of the umbilicus to close -
organs protrude from the abdominal wall

13. Hindgut derivatives
 Left 1/3 of transverse colon
 Descending colon
 Sigmoid colon
 Rectum
 Cloacal membrane at caudal end

14. Anomalies - Hindgut
 Hirschsprung’s Disease – Dilation of the colon – defective
neural crest migration - absence of parasympathetic ganglia
in the colon wall
 Hindgut Fistula - connecting the hindgut to the urogenital
system
 Imperforate anus – absence of anal opening

15. The anus and rectum
develop from the cloaca as
it is divided by the urorectal
membrane into the rectum
posteriorly and urogenital
sinus.
 Anomalies of development
of this system are possible.
Embryogenesis of rectum

16. Organs of the Digestive System

17. Functions of the digestive system
 Digestive - mechanical and chemical
digesting of food, break-down of nutrients for
their absorption, elimination of the waste
products.
5 basic activities:
1. Ingestion
2. Mixing and movement
3. Digestion
4. Absorption
5. Defecation
 Endocrine

18. The main type of nutrition in fetus and child
 Hystotrophic - the embryonic period
 Chemotrophic –
- after formation of the placenta
- based on intracellular digestion
 Amniotrophic –
- after 16-20 weeks of gestation
- the fetus starts to get nutrients
(proteins, glucose, water, minerals)
from the amniotic fluid.
- activity of organs of the digestive
system appears
 Lactotrophic
- after birth

19. Oral cavity
 Breaks down food into
small pieces
 Saliva produces amylase
and lubricates food
 Begins starch digestion
(amylase)
 Moves food into
esophagus
 Epiglottis covers trachea

20. Morphofunctional peculiarities of organs of the digestive system in children
Oral cavity
 Relatively small
 Palatine convexity is not clearly defined
 Tongue is well developed and wide
 Muscles of the lips is well developed
 Inside the cheeks there are well-defined
pads of fat (described by Bichat)
 Secretion of the saliva is very sparse in newborns
 A constant dribbling of saliva is observed at the age of 3-4
months (physiological salivation)
 Neutral reaction (not alkaloid)
 The oral mucosa is extremely delicate, dry and possesses an
abundant vascular network

21. Esophagus
 A straight muscular tube
 It begins at the level of the cricoid cartilage,
inferior to the larynx behind the trachea and
extends through the chest cavity, pierces the
diaphragm at the esophageal hiatus, and
meets with the stomach at an opening called
the cardiac orifice
 It transports food to the stomach and
secretes mucus, which aids transport
 Heartburn- when HCl from the
stomach regurgitates back into the lower
esophagus resulting in a burning sensation

22. Morphofunctional peculiarities of organs of the digestive system in children
Esophagus
 Almost complete absence of glands
 Insufficiency of the elastic and muscular
tissue
 Abundant vascularization
 The narrowings of an esophagus are not
defined
 Its length is 10-11cm (newborn),
12 cm (one year)
16 cm (five-years old child)

23. Morphofunctional peculiarities of organs of the digestive system in children
Stomach
 The fundus is weakly defined
 The cardiac sphincter is in a rudimentary
state
 The pylorus is well developed
 Gastric motility consists of peristalsis, and
periodic closure and dilation of the pylorus
 The automatic innervations - the central
nervous system through the branches of
vagus and the sympathetic nervous system
 The stomach of breast-fed babies is emptied
within 2-3 hours after a feeding, in bottle-fed
babies nursed on cow`s milk evacuation
occurs in 3-4 hours.

24. Volume of stomach in different age
 At birth – 7 ml
 4 days – 40-50 ml
 10 days – 80 ml
After that increase on 25,0 ml/month occurs
 At 1 year – 250 ml
 At 3 year – 400-600 ml
 At 12 year – 1300-1500 ml

25. Function of stomach
Name of stomach’s
glands cells
Secretion Region of stomach
Chief (zymogenic) Pepsinogen
(Chymosin = rennin in
infant)
Fundus only
Parietal (oxyntic) Gastric acid and
intrinsic factor
Fundus only
Mucous neck Mucus gel layer Fundus, cardiac, pyloric
Enteroendocrine
(APUD)
Hormones - gastrin,
histamine, endorphins,
serotonin,
cholecystokinin and
somatostatin
Fundus, cardiac, pyloric

26. Morphofunctional peculiarities of the digestive system in children
Stomach
 The number of chief, parietal cells and glands per unit of the
mucosal surface is less than in adults
 This lack of differentiation in the histological structure is
retained up to the end of the 2nd year of life.
 Stomach digestion consists of two phases: the first is
coagulation of milk, the second includes hydrolysis of the fats
and digestion of casein.
 The absorptive function of the child`s stomach is not very high,
only a very small amount of electrolytes and sugar and also
partly water and the products of protein hydrolysis are absorbed
in the stomach.
 The main mass of food is delivered from the stomach to
intestines for assimilation.

27. Functions:
- Secretory - production HCl (parietal cells)
- Excretory - pepsin (chief cells)
mucus (mucoid and mucoproteins) - additional cells
- Endocrine – pepsinogen, uropepsin, gastrin - autoregulation of enzyme’s
production
- Motor
Peculiarities in children:
- Low acidity (it’s determined by Lactic acid up to 2 months, then -
hydrochloric acid)
- Reduced enzyme activity of gastric juice
- Immunoglobulins of breast milk is stored
- Hydrolysis of fats by gastric lipase in the absence of bile acids
- Evacuation of gastric contents (food) occurs in 3.5 - 4 hours
- Pilorospazm as a manifestation of increased tone of stomach pyloric
sphincter
Functional peculiarities of stomach

28. Morphofunctional peculiarities of organs of the digestive system in children
Small intestine
 The longest section of the digestive tube and consists of
three segments forming a passage from the pylorus to the large
intestine:
 Duodenum - a short section that receives secretions from the
pancreas and liver via the pancreatic and common bile ducts.
 Jejunum - considered to be roughly 40% of the small gut in man,
 Ileum - empties into the large intestine; considered to be about 60%
of the intestine in man,
 Digestion is finished here
 Peristalsis finishes mechanical digestion
 Pancreatic juice produces enzymes to finish chemical digestion of
fats, proteins and carbohydrates

29. Morphofunctional peculiarities of organs of the digestive system in children
Small intestine
 The absorptive surface area of the small intestine is roughly 250
square meters - the size of a tennis court
 The small intestine incorporates three features which account for its
huge absorptive surface area:
 Mucosal folds - the inner surface of the small intestine is not flat, but thrown into
circular folds, which not only increase surface area, but aid in mixing the ingested food
as baffles.
 Villi - the mucosa forms multitudes of projections which protrude into the lumen and
are covered with epithelial cells.
 Microvilli - the luminal plasma membrane of absorptive epithelial cells is studded with
densely-packed microvilli.
 The intestines of an infant is relatively longer than that of adults.
 The intestinal mucosa is well-developed and abundantly vascularized,
rich in cellular elements, very delicate, and contains a great number of
lymph nodes and villi.

30. Morphofunctional peculiarities of organs of the digestive system in children
Small intestine
Intestinal Villi& Microvilli
Mucosal Fold
Three major types of cells in the small intestine
•Enterocytes - the epithelial cells which mature into absorptive epithelial cells
that cover the villi
•Enteroendocrinecells - part of the enteric endocrine system sense the luminal
environment and secrete hormones such as cholecystokinin and gastrin into blood
•Goblet cells, which secrete a lubricating mucus into the intestinal lumen

31.  The infant’s intestine is relatively longer than an adult’s
one:
newborn - 1m per 1 kg; adult - 10 cm to 1 kg of weight
 Intestinal loops are more compact
 The intestineal mucosa is well-developed and
abundantly vascularized, rich in cellular elements, very
delicate, and contains a great number of lymph nodes
and villi.
 High rate of epithelialization
 The relative weakness of the ileocecalis valve
Anatomical and physiological features of small
intestine in children
Three functions – digestion, absorption and motility
 Lactase is an enzyme essential to the complete digestion of lactose
 Low absorption of fat
 Small intestine of infant contains many gases (up to 7 years) –
meteorism
 Permeability is higher
 Muscle fibers (especially longitudinal) are underdeveloped

32. Mesocolon
 Mesocolon–a fold of
peritoneum that binds the large
intestine to the posterior
abdominal wall.
 It is divided into ascending,
transverse, descending, and
sigmoid or pelvic portions,
according to the segment of
the colon to which it gives
attachment.

33.  High motor activity combined with a weak fixation determines
intussusception
 Intussusception occurs when a portion of the intestine folds
like a telescope, with one segment slipping inside another
segment.
Anatomical and physiological features of
large intestine in children
 It is the most common
cause of intestinal
obstruction in children
between 3 months and
6 years of age

34. Intussuseption – typical pathology in infants

35.  The descending colon is larger than the ascending one.
The sigmoid colon and the sigmoid flexure are relatively
longer. The cecum and vermiform appendix are mobile.
 The rectum is relatively long, its mucous and submucous
membranes are loosely attached, hence there is a
tendency to prolapse.
 A more intensive growth of the large intestine is observed
up to puberty.
 Bacteria produce vitamins B and K
Morphofunctional peculiarities of organs of the digestive system in children
Large intestine

36. Intestinal microflora
Phases of microflora formation:
1 - Aseptic - 10-20 hours after birth
2 - Colonization - 2-4 days
3 - Stabilization - 6 months. up to 2 years
Microflora depends on infant’s feeding
Breast feeding
Bifidobacterium bifidum
Artificial feeding
In equal amounts
Bifidobacterium bifidum
Lactobacillus acidophilus
Е. coli

37. Morphofunctional peculiarities of organs of the digestive system in children
The pancreas
The child’s pancreas lacks differentiation, it is
abundantly vascularized and poor in connective
tissue.
Its weight in a newborn is 3g, in a three-months
baby – 6g, in an adolescent – 70-78g, in adults
– 90-120g.
The pancreas possesses an endocrine function
(insulin) and exocrine (pancreatic juice contains
all the enzymes necessary for digesting the
child`s food - amylase, lipase, trypsin)
The duodenal juice is a mixture of the secretions
of the stomach, intestine, pancreas and liver.

38. Anatomical and physiological features of liver
 The biggest organ of abdomen - it takes up to 4% of the body
weight in a newborn, and 2% in an adult.
 Extremely plethoric - a rapid response to infections,
intoxication and circulatory disturbances
 Hepatic cells is not completed differentiated until the age of 6-
8 years – (5% of cells have hematopoietic function in
newborn)
 An intensive growth of the organ is observed in the
prepubertal period.
 Choleresis is slow, but the content of bile acids is higher in
bile (syndrome cholestasis in newborn)
 Difference in chemical structure of bile - taurocholic acid vs
glycocholic
 Antiseptic properties of taurocholic bile acid

39. Features stool in children
 Meconium is composed of materials ingested during the
time the infant spends in the uterus: intestinal epithelial
cells, lanugo, mucus, amniotic fluid, bile, and water.
 Transited stool – 2-5 days
 From 5 day – yellow stool, acid reaction
 Number of defecation:
 newborn - 6-7 times per day
 from 2 mo. – 3-6 times per day
 1 year – 2-3 times per day

40. The methods of clinical investigation of the
digestive system
1. interrogation
2. observation
3. palpation
4. percussion
5. auscultation

42. Caput medusae

43. Abdominal regions

44. Obese abdomen
Hepatomegaly
Observation
1. Ask the patient to lie on a level examination
table that is at a comfortable height for both
of you
2. The patient's hands should remain at their
sides with their heads resting on a pillow
3. The patient should be undressed
4. The patient should be examined in
horizontal and vertical positions
5. Keep the room as warm as possible and
make sure that the lighting is adequate

45. Caput medusae
also known as palm tree sign
It is a symptom of portal hypertension.
It is caused by dilation of the paraumbilical veins, which
carries oxygenated blood from mother to fetus in utero and
normally closes within one week of birth, becoming re-
canalised due to portal hypertension caused by liver failure.

46. Observation
Geographic tongue
 is a common condition, associated with life stresses
(common cold, work/home stresses), allergy

47. Observation
Furrowed tongue
 The grooves tend to appear and get deeper or more
prominent
 Chronic diseases of digestive system

48. Observation
Hairy tongue
•due to the fact that the filiform papillae elongate
and do not desquamate normally.
•It can be triggered by many things, such as
smoking, medications like antibiotics, and others.

49. Observation
Smooth tongue
 Vitamin deficiency (vit. B) and anemia

50. Auscultation
Compared to the cardiac and
pulmonary exams, auscultation of
the abdomen has a relatively minor
role.
It is performed before percussion or
palpation as vigorously touching the
abdomen may disturb the intestines,
perhaps artificially altering their
activity and thus bowel sounds.
Bowel sounds can, however, add
important supporting information in
the right clinical setting.

51. Percussion
There are two basic sounds
which can be elicited:
 Tympanitic (drum-like)
sounds produced by
percussing over air filled
structures.
 Dull sounds that occur
when a solid structure (e.g.
liver) or fluid (e.g. ascites)
lies beneath the region
being examined.

52. Palpation
 The patient lies on back,
shoulders raised slightly and
legs flexed to relax the
abdomen.
 He should keep his mouth open
and breathe quietly and deeply.
 The abdomen is palpated with
the flat of the hand initially and
the fingers are used to locate
the margins of any viscera or
tumour.
 The patient should have an
empty bladder.

56. The main methods of paraclinical investigation
 Laboratory
 Coprogramma – clinical analysis of feces
 Bacteriological investigation of stool
 Investigation feces for worms (helminthes) and eggs
of worms
 Biochemical methods
 Instrumental
 Ultrasound method
 Functional investigation of the digestive organs
 Roentgenological methods
 Computer tomography
 Cholyscintigraphy
 Endoscopy
 Angiography

57. Coprology examination
 Patient Age
̶ Form
̶ Consistence
̶ Color
̶ Mucus
̶ Pus
̶ Blood
̶ Chemical examination presence
of stercobilin
 Microscopic examination
̶ Connective tissue
̶ Muscular fibres
̶ Neutral fat
̶ Fatty acids
̶ Soaps
̶ Not digested cellulose
̶ Digested cellulose
̶ Starch
̶ Mucus
̶ Leukocytes
̶ Erythrocytes
̶ Epithelium
̶ Protozoas
̶ Eggs of worms

58. The ultrasound method

59. Endoscopy

60. Colonoscopy

61. Biopsy during endoscopy

63. The main pathological syndromes of the
digestive system’s diseases
 Pain syndrome
 Dysphagia
 Dyspepsia
 Gastro-esophageal reflux
 Gastro-entero-colitis
 Bleeding
 Malabsorption
 Jaundice syndrome
 “Acute abdomen”

64. Pain syndrome
 Connection with feeding
 Localization
 Irradiation
 Character
 Seasonality

65. Pain syndrome depended on localization

70. Syndrome gastroenterocolitis
 Gastritis
 Vomiting
 Pain in epigastric region
 Enteritis
 Toxicosis
 Fluid stool without pathological admixture
 Dehydration
 Colitis
 Volume of stool is little
 A lot of mucus, blood
 Dehydration is absent – toxicosis is prevalent

71. Bleeding syndrome
 Hematemesis
vomiting blood
red: from esophagus
black & granular
 “coffee grinds”
 from stomach
 Melena
black, tarry stools
 Occult bleeding

73. Syndrome of mechanical obstruction
pain
vomiting
abdominal distention
lack of stools
hyperactive bowel sounds

74. Mechanical Obstruction
 Hernias
 protrusion of bowel
through a hiatus or
defect

75. Mechanical Obstruction
 Intussusception
telescoping of
bowel where distal
segment
“swallows” proximal
segment

76. Malabsorption Syndrome
 Malabsorption is a state arising from abnormality in
absorption of food nutrients across the gastrointestinal tract.
 Clinical signs
 Diarrhoea, often steatorrhoea
 Weight loss
 Growth retardation, failure to thrive, delayed puberty
 Swelling or oedema from loss of protein
 Anaemias, commonly from vitamin B12, folic acid and iron
deficiency
 Muscle cramp (decreased vitamin D, calcium absorption) -
osteomalacia and osteoporosis
 Bleeding tendencies from vitamin K and other coagulation
factor deficiencies

77. Icterus Syndrome
 Level bilirubine more than 20,5-34,5 mкmol/l
(newborns – more than 68,4-85,5 mкmоl/l)
 Types of icterus
Mechanical obstruction
Parenchymal
Hemolytic

82. Thank your for attention!