Dr. Soad Jaber2009

Objectives

Criteria for establishing a diagnosis of diarrhea

Explain the major risks and identify the sign and symptoms of high risk patients.

Find clues in hx and examination to D.D Select laboratory tests Select management options.

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© 2007 Elsevier

b. Non infectious:

1. Feeding difficulties 2. Anatomic defects.

Short bowel syndromeMalrotationMicro villous atrophyfecal impaction

3. MalabsorptionDisaccharidase deficienciesPancreatic insufficiencycystic fibrosis

4. Endocrinopathies:ThyrotoxicosisAdrenogenital syndrome

5. Food poisoning – heavy metals.e.g copper ,mushroom toxines

6. Neoplasm:NeurofibromatosisPheochromocytoma

7. Miscellaneous:Milk allergyCrohn’s diseaseProtein loosing enteropathyLaxatives abuseAcrodermatitis enteropathicaAIDS enteropathy

Viral Bact ParasitesRota virus Campylobacter. Giardia lambiaNorwalk virus Escherichia coli entameba

Adeno virus Salmonella

ShigellaVibrio choleraclostridium dificile

o Young ageo Immune deficiencyo Measles o Malnutrition o Low gastric acidity

o Poor nutrientso Living or visiting endemic areao Exposure to unsanitary conditionso Ingestion of contaminated food or watero Level of maternal educationo Day care center attendanceo Abnormal bowel flora (antibiotics)o Lack of breast feeding

o \

Sterile IgA content Lactoferrin Antiviral factors

Clinical manifestation Physical examination The patho physiological mechanism of

entero Pathogen.a. Inflammatory diarrhea : Usually by bacteria which invade the intestine directly or produce cytotoxinb. Non inflammatory through Enterotoxin production by some bacteria Destruction of surface cell by virus

Entero pathogens that are infectious in small inoculums.

ShigellaGiardia LambiaE. ColiCrypto Sporidium

Rota virus Entamoeba histolytica

Mode of infection person → person Feco-oral route**cholera are a consequence of contaminated food or

water.

Viruses Secretory type of diarrhea Invade the epithelium of the

small intestine. Lysis of enterocytes … interfere

with brush borderfunction - malabsorption of electrolytes _ and sugar

1. Rota Virus

I.P. 1-3 d Duration diarrhea 7-10 d

vomiting 3 - 4 d Cause 70% of episodes in children below 2 years old

both in developed and under developed countries. winter Often preceded by respiratory illness. Maternal antibodies can protect infants below 3

months of age

Diagnosis : ELISA Rotazyme

2. Norwalk Virus I.P. 1-3 days

duration 1 – 2 daysEpidemics of acute gastro enteritis in school, camps outbreaks in adults and young childrenAttack rate of family contacts high

3. Enteric adeno Virus I.P. 8- 10 days

duration 5 - 14 days Asymptomatic Watery diarrhea vomiting +

fever Stool -ve RBCs .-ve WBCs Respiratory symptoms

Mechanism of action:1. Elaboration of toxins (Entero toxigenic

pathogen)

- Bacteria colonize the intestine.- Bacteria do not invade the small bowel or

destroy enterocytes- Bacteria multiply and produce enterotoxins that bind the receptors on the surface of the mucosal cells.- Secret isotonic fluid from crypt cells. example: staphylococcus aureus.

CIP: Watery diarrheaLarge volume-ve WBC&RBCs in stoolNo tenesmus or fever

or myalgia nausea vomiting

Inflammation of the intestine: abdominal cramps + pain.

Systemic signs: myalgia – fever – arthralgia. Irritability. Loss of appetite.

Frequent passing of small amount of stool (mucous)

WBC + RBC+++

Example: ShigellaInvasive E-coliSalmonellaCampylobacter

Enteropathogens cause non inflammatory diarrhea through enterotoxins

Destruction of the villous surface by viruses,adherence by parasite

Salmonella:Common pathogen in infants 6m

Nosocomial infection

20 times more common in patients with:› AIDS› SCD› RES dysfunction

Ingestion of contaminated meat, dairy ,poultry products

Need large inoculumsRare persons Person

Resistant to drying (Commercial products)

Invade distal ileum inflammation of intestine

Toxigenic diarrheaI.P. 24 – 36 hMild short illness 2-3daysVomiting – abdominal cramps - bloody

diarrhea

EPEC - Epidemics in nursery + day careETEC - toxins – induce intestinal secretion

absorptionTravelers diarrhea

EIEC - Invade colonic epitnelium. mucosal injury inflammation

EAECEHEC - HUS

IP 1-7 days2/3 watery diarrhea1/3 bloody diarrhea

invasive – enterocolitis 1 year of life Reservoirs : animal species,

chicken,dogs Fecal – oral route -

PersonTO person

Giardia LambiaProminent cause of diarrheaIngestion of only a few organism –

infectionSpread – contaminated water supply

person to personChild Care Center

Multiply in small bowelRarely invade mucosaSymptoms; Abdominal distention

crampingmild nausea? Severe weight loss

D/ cyst in stool x3 Elisa in stool.

Mild diarrheaSevere colitisMultiple bloody stoolsSerious infection in patients less

than 2years,high mortality, amoebic liver abcess

management

1st discriminate if the child have a serious problem which mandate a major management

Is dehydration electrolyte imbalance or acidosis present

Is it acute diarrhea of viral origin which is self limited.

Evaluation of serious condition

Systemic sepsis:.invasive bac infection NEC,pseudo membranous colitis,

HUS,Parasitic colitisStep 1:evaluate for sepsisStep2:evaluate for acute abdomenStep3:stool ex for blood and leukocytes

(PMN or eosinophils)Step4:evaluate the stool for

bacteria .routine or special media.

Enteric infection can cause:1. GIT symptoms

Diarrhea Cramps emesis

2. Systemic Fever Malaise Seizure

3. Extra Intestinal infection Osteomyelitis Meningitis Pneumonia Hepatitis

4. Immune mediated extra intestinal manifestation of enteric pathogen usually occur after diarrhea has resolved

Reactive arthritisSalmonella

ShigellaGuillian Barre

Campylobacter

1. Assess the degree of dehydration Provide fluid and electrolyte

replacement2. Prevent spread of enteropathogen3. In selected cases determine the

etiologic agent and provide specific therapy if indicated.

Ask about: Oral intake Frequency and volume of stool output General appearance and activity of the

child Frequency of urination

Symptoms:

Fever - inflammatory process

- dehydration

Non specific - nausea- emesis

Vomiting → organism in upper intestinal tract (viruses)

Severe abdominal pain + tenesmus → large intestine

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© 2007 Elsevier

Stool analysis: Blood Leukocytes - Invading bacteria cytotoxin producing Shigella, Salmonella, Ecoli Stool culture early: Special media for V. Cholera Campylo bacter Procto… Segmoidoscopy

1. Dehydration:More severe in childrena. greater basal fluid + elect requirement / kgb. dependent on others for the demands

Assess the degree of dehydration:Clinical signs and symptomsOngoing lossesdaily requirement

Mod 5-Mod 5-9%9%

Mild <5%Mild <5% Severe Severe >10%>10%

Blood Blood PressurePressure

Pulse Pulse pressurepressure

Heart rateHeart rate

SkinSkin

FontanelFontanel

Mucous Mucous memomemo

ExtremitiesExtremities

Mental Mental statusstatus

Urine outputUrine output

ThirstThirst

NormalNormal

NormalNormal

NormalNormal

NormalNormal

NormalNormal

Slightly Slightly drydry

PerfusePerfuse

NormalNormal

Slightly Slightly

N to N to N to N to TurgorTurgor

NormalNormal

DryDry

Delay capill Delay capill refillrefill

N or N or lethargiclethargic

TachycardiaTachycardia turgorturgor

SunkenSunken

DryDry

Cool ,mottleCool ,mottledd

Lethargic, Lethargic, comacoma

AbsentAbsent

To all patient but:1. Severe dehydration in patient whose care

giver can’t administer fluids.2. If ongoing losses can’t be compensated

orally.3. Severe vomiting.

Value:Rapid rehydration with rapid replacement of ongoing losses during the first 4-6 hours.Once rehydrated – oral maintenance solutions.

WHOWHO PEDIALYTPEDIALYTEE

CHOCHO

NaNa

KK

HCO3HCO3

OsmolariOsmolaritt

2%2%

90 mmol/L90 mmol/L

20 mmol/L20 mmol/L

30 mmol/L30 mmol/L

310310

2.5%2.5%

4545

2020

3030

250250

Home remedies?› Decarbonated soda beverages› Fruit juices› Tea

Not suitable:› Inappropriate high osmolarities

due to CHO conc.› Low Na content → hypo natremia› Inappropriate CHO to Na ratio

Introduce food Oral electrolyte solution is

continued to replace ongoing losses from stool

Breast feeding

Action:a. Alternation of intestinal motilityb. Absorption of fluid and toxinsc. Alternation of intestinal micro florad. Alteration of fluid and electrolyte

secretion

Minimal benefit Potential for side effects

Campylobacter ErythromycinCholera Tetracycline

or TMP / SMXSalmonella Ampicillin

or chloramphenicol

or TMP / SMXShigella TMP / SMX

Cefixime

Giardia lambiaMetronidazole

Entameba HistolyticaMetronidazole

Hospitalization:Enteric Precaution

Soiling – hand washTouching – gloves

Vaccines:Salmonella typhiCholera

Food productsAlteration of dietary habitsLack of recognition of methods of prevention Should be considered when two or more

persons who have ingested common food or water develop a similar acute illness that usually is characterized by: nausea, emesis, diarrhea

Pathogenesis and severity depend on: - whether organisms perform toxins Staph

Aureus- Invasive organism- Whether they replicate in the food.

Severity of disease depend on amount of inoculated organism in food or water.

Incubation period: 1 hour - chemical poisoning, fish

performed toxins S. Aureus

Symptoms:Nausea and vomiting 1-6 h A aureusWatery diarrhea and abd cramps 8-12 h C

perfingens1648 h

Vibrio choleraDiarrhea, fever, abd cramps 16-72 h Salmonella

ShigellaBloody diarrhea, abd crap 72 h E.H., E ColiParalysis, nausea, vomiting 18-48 h

ClostridiumBotulism