1. The epidemiology and etiology of diarrhea

2. Diarrhea in young children
3-4 episodes /child / year
death / year
Causes about 30% of infant death in developing countries
80% death due to diarrhea occur in first years of life
Diarrhea is an important cause of malnutrition

3. Three clinical types of diarrhea
Acute watery diarrhea dehydration ,potassium loss
Bloody diarrhea tissue damage, toxemia
Persistent diarrhea malnutrition

4. Host factors that increase susceptibility to diarrhea
Failing to breast - feed until at least 2 years
Malnutrition
Measles
immunosuppression

5. Behavioral risk factors for diarrhea
Inadequate breast feeding
Using feeding bottles
Eating food hours after cooking it
Drinking contaminated water
Not washing soiled hands
Not disposing of feces

6. Prevention of diarrhea ( host factors)
Breast feed at least 2 years
Give plenty of good food ,start at age 4-6month
Immunize against measles

7. Fluids for home therapy
ORS solution
Water
Food - based fluids
soup
rice water
Yoghurt drink
Glucose water

8. Age of diarrhea
Most diarrhea episodes occur during the first 2 years of life
Incidence is highest in the age group 6-11 month
Declining levels of maternally acquired antibodies
The lack of active immunity in the infant
The introduction of food

9. seasonality In temperate climate ;
bacterial diarrhea occur more frequently during the warm season
whereas the peak Viral diarrhea particularly rotavirus is during the winter
In the tropical areas;
rotavirus diarrhea occurs throughout the year and increasing in cool month Whereas bacterial diarrheas peak during warmer ,rainy season
The incidence persistent diarrhea follows the same seasonal pattern as that acute watery diarrhea

10. Etiology of diarrhea Rotavirus Enterotoxigenic Escherichia coli
Shigella
Campylobacter jejuni
cryptosporidium
Vibrio cholera
salmonella (Non thyphoid )
Entropathogenic Escherchia coli

11. Pathogenic mechanisms ( viruses)
Replicate within the villous epithelium of small bowel
Patchy epithelial cell destruction and villous shortening
The Loss of normally absorptive villous cells
Replacement immature , secretary ,crypt- like cells
Loss of disaccharides , especially lactose

12. Pathogenic mechanisms )bacteria)
Mucosal adhesion to avoid being swept away
Entrotoxicogenic E.coli ,vibrio .cholera
Toxins that cause secretion that reduce the absorption of Na and increase the secretion of chloride
Entrotixigenic E.coli , v.cholera
Mucosal invasion occurs in the colon and distal ileum and destroying mucosal epithelial cells and cause bloody diarrhea
Shigella ,C.jejuni ,entroinvasive E. coli and salmonella

13. Pathogenic mechanisms )protozoa)
Mucosal adhesion and cause shortening of the villi
G,lambelia , cryptosporidum
Mucosal invasion in the colon or ileum and causing micro absess and ulcer
E, histolitica

14. Campilobacter jejuni C,jejuni causes disease mostly in infants
C,jejuni also infects animals and spread by contact with their
feces or consumption of contaminated food , milk , or water
C,jejuni can cause watery diarrhea or dysentery
Fever may be preset and episodes are not sever and last 2-5 days
Erythromycin shorten the illness

15. cryptosporidium
This parasite causes diarrhea in infants immunodeficient patients , and a variety of domestic animals
Infection is frequent in developing countries
Most episodes of illness occur in the first year of life
Diarrhea is usually neither severe nor prolonged
Diarrhea is sever in malnutrition , or AIDS , immunodeficient patients

16. Prevention of diarrhea
Give only breast milk for first 4-6 month
Do not use feeding bottle
Prepare and store food safely
Use clean water for drinking
Wash hands when soiled
Dispose of faeces safely

17. Treatment of acute diarrhea the main points
Replace lost water and salt
Continue to feed

18. Benefit of antibiotics in acute diarrhea
Helpful for patients with ; %
Bloody diarrhea
Suspected cholera with severe dehydration
No practical value for others because ; %
Ineffective for pathogen
Pathogen not known

19. Treatment acute diarrhea other points
Only give antibiotic for ;
Bloody diarrhea
Suspected cholera with severe dehydration
Only give anti protozoals ;
No response to treatment for shigella
Proven amebiasis

20. Treatment of diarrhea Replacement of fluids and electrolytes
Feeding should be continued in all types of diarrhea
Antimicrobial and anti parasitic agents should not be used

21. Treatment of diarrhea
Antimicrobial and anti parasitic agents should not be used exception is ;
Dysentery
Suspected cholera with sever dehydration
Persistent diarrhea when trophozoites or cysts of giardia or trophozoites of E,hystolytica are seen in feces or intestinal fluid or pathogenic enteric bacteria are identified by stool culture

22. Pathophysiology of watery diarrhea

23. Pathophysiology of watery diarrhea
Normally absorption and secretion of water and electrolytes occur throughout the intestine
Water and electrolytes are simultaneously absorbed by the villi and secreted by the crypts
More than 90% of the fluid entering the small intestine is absorbed
Only cc of water excreted each day in formed stools

24. Absorption and secration
 Villus
Active absorption of Na
Na absorbed with glucose and aminoacids
 Crypt ;
Active secretion of choloride

25. Pathophysiology of watery diarrhea
Watery diarrhea is caused by a disturbance in the mechanism of transport of water and electrolytes in the small intestine
Intestinal transport mechanisms are also the basis for the management of diarrhea

27. Intestinal absorption water and electerolytes
Absorption water from the small intestine is caused by osmotic gradients that created when Na are actively absorbed

28. Mechanisms of the watery diarrhea
There are several mechanisms for Na absorption
Na is linked to the absorption of chloride ion
Absorbed directly as Na ion
Exchanged for hydrogen ion
Or linked to the absorption of organic substances such as glucose or certain amino acids

29. Intestinal secretion of water and electrolytes
Secretion of water and electrolytes normally occurs in the crypts
Na is transported from the ECF into the epithelial cell
Na is then pumped back into the ECF by Na k ATPase
Secretory stimuli cause chloride ions to pass through the luminal membrane of the crypt cells into the bowel lumen
Osmotic gradient that causes water and electrolytes to flow passively from the ECF into the bowel

30. Mechanisms of the watery diarrhea
There are two principal mechanisms ;
Secretion
Osmotic action
 intestinal infection can cause diarrhea by both mechanisms.
Secretory diarrhea is more common
Both mechanisms may occur in a single individual

31. Secretory diarrhea
There is abnormal secretion of water and electrolytes into the small bowel
Absorption Na by the villi is impaired
Secretion chloride in the crypt cell cotinuous or increased
fluid secretion and Loss water and Na as watery stools , and dehydration

32. Causes of secretory diarrhea
Toxicogenic bacteria
Vibrio cholerae
E,choli
Campilobacter
Shigella
Salmonella
 Enteric viruses
ritaviruse

33. Osmotic diarrhea
Water and electrolytes move rapidly across the epithelium of small bowel mucosa to maintain osmotic balance
Diarrhea can occur when a poorly absorbed osmotically active substance is ingested

34. Osmotic diarrhea
If the substance is isotonic solution causing diarrhea but not dehydration (lactose , glucose , magnesium sulfate )
If non absorbed substance is hypertonic solution water move from the ECF into the gut ,that causes diarrhea with dehydration and hypernatremia

36. Causes of osmotic diarrhea
Product unabsorbed solution
Milk lactose ,small organic acids
Sweetened drink sucrose , glucose
Laxative salts magnesium sulfate

38. Isotonic dehydration  This is the most type of dehydration
 Losses of water and Na are in the same proportion
There is a balanced deficit of water and Na
Serum Na concentration is normal ( m mol / l )
Serum osmolality is normal ( )
Hypovolemia occurs as a result of loss of extra cellular fluid

39. Hypernatremic dehydration
 There is loss of water excess of Na
 It is usually results from ;
ingestion of hypertonic fluid that not efficiently absorbed
Insufficient intake of water or low –solute drink
There is a deficit of water and Na deficit of water is greater
Serum Na concentration is elevated (>150 mmol/l)
Serum osmolality is elevated (>295m osmol/l )
Thirst is severe and the child is very irritable
Sezures may occur (Na >165 mmol /l)

40. Hyponatremic dehydration
 There is loss of Na excess of water
It is usually from ;
drink large amounts of water or hypotonic fluid with low Na
IV infusion 5%glucose without Na
There is deficit of water and Na but the deficit of Na is greater
Serum Na concentration is low (<130 mmol /l)
Serum osmolality is low (<275 mosmol /l)
The child is lethargic , infrequently seizures

41. Metabolic acidosis
during diarrhea a large amount of bicarbonate may be lost in the stool if the kidneys have normal function much of lost bicarbonate is replaced
when patients have hypovolemia ;
Excessive production of lactic acid
there is poor renal flow and fail the compensating mechanism
 Serum bicarbonate concentration is reduced (<10 mmol/l)
 Arterial PH is reduced (<7.10)
 Breathing become deep and rapid
 Vomiting is increased

42. Metabolic acidosis
Serum bicarbonate concentration is reduced (<10 mmol/l)
Arterial PH is reduced (<7.10)
Breathing become deep and rapid
 Vomiting is increased

43. Metabolic effect of watery diarrhea
Loss of water and salt hypovolemia shock
Excess loss of bicarbonate acidosis
Excess loss of K K deplation

44.  Patients with diarrhea often develop K depletion
hypokalemia
 Patients with diarrhea often develop K depletion
 When K and bicarbonate are lost together hypokalemia does not usually develop
The signs of hypokalemia may include ;
General muscular weakness
Cardiac arrhythmias
Paralytic ileus

45. اثر گلوكز در جذب روده اي نمك و آب در زمان اسهال

46. Oral rehydration therapy
ORT is based on the principle that intestinal absorption of Na is enhanced by the active absorption of glucose and aminoacids

47. Oral rehydration therapy
ORT is based on the principle that intestinal absorption of Na is enhanced by the active absorption of glucose and aminoacids
This process is normal during secretory diarrhea
If patients with secretory diarrhea drink an isotonic salt solution without glucose or aminoacids Na is not absorbed
When a balanced isotonic solution of glucose and salt is given
glucose linked Na absorption occurs and this is accompanied by the absorption of water

48. ORS an osmolality similar to or less than plasma
The concentration of Na should be sufficient to replace the Na deficit
The ratio of glucose to Na should be at least 1:1
The concentration K should be 20 mmol/l
The concentration base should be 10 mmol /l for citrate or citrate or 30 mmol/l for bicarbonate
Na= 90 k=20 Cl=80 Hco3=30 Glucose =111

49. When ORT is not effective
Severe repeated vomiting
Severe diarrhea >15 cc /kg /h
Glucose malabsorption

50. ORT inappropriate for paralytic ileus abdominal distension
initial treatment of Severe dehydration because fluid must be replaced very rapidly
Patients who are unable to drink

51. Assessing the patient with diarrhea
Ask, look and feel for dehydration
General condition?
Well , alert?
Restless ,irritable?
floppy,lethargic, or unconscious?

52. Assessing the patient with diarrhea
Eyes:normal? Sunken? Very sunken and dry?
Tear: have tear?
Mouth and tongue: wet? dry?very dry?
Thirst: drinks normal?drinks eagerly?drinks poorly?
Skin pinch: immediately? Slowly(>2se) ? very slowly?
Additional sign: anterior fontanel?pulse? Breathing?

53. Determine the degree of dehydration and select tereatment
Two or more signs in one column including at least one key sign means that the patient falls in that category.
C-severe dehydration deficit equal more than 10%
B- some dehydration ( mild or moderate ) deficit equal %
A-no dehydration

54. Assessing the child for other problems
Dysentry?
Persistent diarrhea?
Malnutrition?
Feeding history? Pre-illness , feeding during diarrhea and mother,s beliefs
Physical finding? Sings of marasmus or kwashiorkor?

55. Treatment plan a to treat dirrhea at home
Explain 3 rules for treating diarrhea at home:
Give the child more fluid for prevent dehydration
Give the child plenty of food to prevent malnutrition
Take the child to the health worker if the child not get better in 3 days or develops any of the following:
Fever , eating or drinking poorly , bloody stool , marked thirst , repeated vomiting , many watery stools

56. Treatment plan a to treat dirrhea at home
Give ORS at home if:
they have been on treatment plan B or C
They can not return to the health worker if the diarrhea worse
It is national policy give ORS to all children

57. If the child will be given ORS at home
Age less than 24 months ml after each loose stool and 500ml /day at home
2-10 year ml after each loose stool and 1000ml / day
10 years or more as much as wanted and 2000ml/ day
Give a teaspoon every 1-2 minutes for under 2 year
If a child vomits wait 10 minutes and then every 2-3 minutes

58. Treatment plan B to treat dehydration
Estimate the amount of ORS solution to be given during the 4 hours
To show the mother how to give ORS
To continue breast- feeding
To monitor treatment and reassess the child
To identify patients who can not be treated satisfactory
After rehydration following planA

59. Treatment plan B Amount of ORS is75ml /kg in the 4 hours
If the child wants more ORS give more
The mother continue breast- feeding
For infant < 6 month who are not breast – fed give ml water
after 4 hours reassess the child then select plan A,B , C

60. Thanks…
But it’s not the end !!