BacterialBacterial Gastrointestinal InfectionGastrointestinal Infection2-Year Medical Students2-Year Medical Students

Prof .Dr. Asem ShehabiProf .Dr. Asem ShehabiFaculty of MedicineFaculty of MedicineUniversity of JordanUniversity of Jordan

Diarrheagenic Diarrheagenic E. coli-1E. coli-1

There are There are 6 groups of 6 groups of E. coli E. coli strainsstrains which have which have virulence factors causing human diarrhea..Widely virulence factors causing human diarrhea..Widely distributed in water, animals & Birds..distributed in water, animals & Birds..4 most important4 most important

1-Enterotoxigenic E. coli 1-Enterotoxigenic E. coli (ETEC). Common in domestic (ETEC). Common in domestic animals, Poultry, Humans ..Produces animals, Poultry, Humans ..Produces Heat Heat stable stable //Heat –labile enterotoxinsHeat –labile enterotoxins (plasmid borne) or both (plasmid borne) or both ((LT+ STLT+ ST).. fimbrial adhesins attached to enterocytes of ).. fimbrial adhesins attached to enterocytes of the proximal small intestine epithelium..the proximal small intestine epithelium..

LT Subunit BLT Subunit B.. attached to GM1 Ganglioside.. release .. attached to GM1 Ganglioside.. release Subunit A.. Activate adenylyl cyclase .. increase Subunit A.. Activate adenylyl cyclase .. increase cellular cellular cAMP release cAMP release .. Heat-stable toxin .. Heat-stable toxin (ST) (ST) activates activates cGMPcGMP.. Both cause prolonged hyper .. Both cause prolonged hyper secretion of water .. Sodium + chloride.. Inhibit secretion of water .. Sodium + chloride.. Inhibit reabsorption of sodium.. Mild/severe watery diarrhea, reabsorption of sodium.. Mild/severe watery diarrhea, vomiting, abdominal pain.. No fever.vomiting, abdominal pain.. No fever.

E. coliE. coliMucosal Attachment .. Mucosal Attachment ..

AdhesionsAdhesions Fimbriae-Pili.. CFA I & CFAFimbriae-Pili.. CFA I & CFA II II

Diarrheagenic Diarrheagenic E. coli-2E. coli-2 ETECETEC strains strains are an important cause of diarrhea in are an important cause of diarrhea in

infants – very young children in developing countriesinfants – very young children in developing countries Common cause of Common cause of Traveler’s diarrhea Traveler’s diarrhea in developed in developed

countries.. Contaminated water .. Dairy products.. countries.. Contaminated water .. Dairy products.. fresh vegetable food. fresh vegetable food.

Self- limited with Rehydration.. Self- limited with Rehydration.. Antibiotics are rarely Antibiotics are rarely needed. needed.

2-2- Entero-haemorrhagic Entero-haemorrhagic E. coli E. coli (EHEC) (EHEC) or Vero-or Vero-toxigenictoxigenic E. coli (VTEC).. E. coli (VTEC).. mostly serotypemostly serotype O157: H7.. O157: H7.. Produces Shiga-like toxinProduces Shiga-like toxin.. common in intestines of .. common in intestines of animals.. cows.. contamination milk & ground beef animals.. cows.. contamination milk & ground beef meat.. causes outbreaks of gastroenteritis ..4000 meat.. causes outbreaks of gastroenteritis ..4000 cases, 600 HUS, 55 deaths.. 2012,Germany cases, 600 HUS, 55 deaths.. 2012,Germany

Diarrheagenic Diarrheagenic E. coli-3E. coli-3 Complications..Complications.. severe inflammation & ulceration colon.. severe inflammation & ulceration colon..

bleeding.. bleeding.. Haemorrhagic colitisHaemorrhagic colitis.. .. If toxin reached blood.. If toxin reached blood.. Haemolytic Uraemic Syndrome Haemolytic Uraemic Syndrome (HUS).. More severe in (HUS).. More severe in children.. Blood+ Protein in urine.. Kidney failure ..fatal children.. Blood+ Protein in urine.. Kidney failure ..fatal

Prevention is better than treatment with antimicrobials.Prevention is better than treatment with antimicrobials. 3-3-Entero-pathogenicEntero-pathogenic E.coli E.coli (EPEC).. adherence to GI (EPEC).. adherence to GI

epithelium.. distortion.. Numerous serotypes.. K, epithelium.. distortion.. Numerous serotypes.. K, LPSLPS Antigens .. Common infection in neonates.. Outbreaks in Antigens .. Common infection in neonates.. Outbreaks in babies nurseries aged less 6 months.. watery diarrhea & babies nurseries aged less 6 months.. watery diarrhea & vomiting.. Chronic diarrhea.vomiting.. Chronic diarrhea.

4-4-Entero-invasiveEntero-invasive E.coli E.coli ( (EIEC).. like Shigella.. cause EIEC).. like Shigella.. cause bloody diarrhoeabloody diarrhoea.. Vomiting.. Abdominal pain.. Fever.. by .. Vomiting.. Abdominal pain.. Fever.. by invasion of damaging intestinal epithelial cells.. necrosis.. invasion of damaging intestinal epithelial cells.. necrosis.. Affect all ages..more pathogenic in children.Affect all ages..more pathogenic in children.

Lab DiagnosisLab Diagnosis Detection of Diarrheagenic E. coli strains Detection of Diarrheagenic E. coli strains in the in the

laboratory is difficult.. complicated by the fact that non-laboratory is difficult.. complicated by the fact that non-virulent E. coli strains are normally present in the virulent E. coli strains are normally present in the feces.. Lactose+vefeces.. Lactose+ve

Stool culture.. MacConkey agar.. Identification by Stool culture.. MacConkey agar.. Identification by PCR PCR more accurate than biochemical and serotyping.. more accurate than biochemical and serotyping..

Antibiotic treatment is recommended in severe & Antibiotic treatment is recommended in severe & chronic cases.. Ciprofloxacin, Co-trimoxazole is chronic cases.. Ciprofloxacin, Co-trimoxazole is recommended for drug-sensitive strains.... parenteral recommended for drug-sensitive strains.... parenteral second-generation or third-generation cephalosporin second-generation or third-generation cephalosporin for systemic complications. for systemic complications.

No vaccines are availableNo vaccines are available

CampylobacterCampylobacter Campylobacter spp. are Microaerophlic.. Gram-negative ..Campylobacter spp. are Microaerophlic.. Gram-negative ..Spiral Spiral

shape.. Bipolar flagella.. shape.. Bipolar flagella.. Motile.. Isolation on Motile.. Isolation on selective special selective special medium at 42 Cmedium at 42 C. .

Commonly present in the GIT of Commonly present in the GIT of domestic animals.. poultry & domestic animals.. poultry & petspets .. Contaminate easily Meat.. Dairy products.. Food .. Contaminate easily Meat.. Dairy products.. Food contamination & direct contact with animals.. Common cause of contamination & direct contact with animals.. Common cause of diarrhea in Western countries..Less in Arab countries.diarrhea in Western countries..Less in Arab countries.

Campylobacter jejuniCampylobacter jejuni.... common cause common cause acute enteritisacute enteritis.. Bloody .. Bloody diarrhea.. Infants, children > adults, Elderly, Immune- diarrhea.. Infants, children > adults, Elderly, Immune- compromised.. Rare septicemia.. Reactive arthritis.. Infection compromised.. Rare septicemia.. Reactive arthritis.. Infection mostly mostly self-limited without treatmentself-limited without treatment.. few days.. Pathogenesis.. .. few days.. Pathogenesis.. Endotoxin & various enterotoxin, cytotoxins..Prolong carriage Endotoxin & various enterotoxin, cytotoxins..Prolong carriage associated with imunodeficincey. associated with imunodeficincey.

C. fetusC. fetus.. .. Less common in human.. Causes sepsis & abortion Less common in human.. Causes sepsis & abortion in animals. in animals.

Serological test is not significant in diagnosis clinical cases.Serological test is not significant in diagnosis clinical cases. Treatment: Macrolides/Azithromycin, Ciprofloxacin, AmpicillinTreatment: Macrolides/Azithromycin, Ciprofloxacin, Ampicillin

Campylobacter- Campylobacter- Vibrio choleraVibrio cholera

Helicobacter pyloriHelicobacter pylori H. pylori H. pylori infection is expected to be present in infection is expected to be present in

stomach of stomach of 30%-9030%-90% of world’s population ..causes no % of world’s population ..causes no signs or symptoms and doesn't lead to any signs or symptoms and doesn't lead to any complications in the majority of persons.. complications in the majority of persons.. H. pylori H. pylori infection infection discovered 1983 as cause of discovered 1983 as cause of chronic chronic gastritisgastritis.. Serious complications.. Serious complications.. .. Peptic /dudenal Peptic /dudenal ulcers.. Lymphoma,ulcers.. Lymphoma, stomach cancer stomach cancer in 2% of colonized in 2% of colonized persons persons worldwide worldwide over a long period over a long period

H. pyloriH. pylori ....Microaerophlic to Anaerobes.. Gram-ve Microaerophlic to Anaerobes.. Gram-ve bacteria, spiral shape, motile, polar 4-6 flagella .. bacteria, spiral shape, motile, polar 4-6 flagella .. produces potent produces potent urease, urease, support its survive in gastric support its survive in gastric mucous layer near the epithelial surface.. neutralize mucous layer near the epithelial surface.. neutralize stomach acidity. stomach acidity. Protease & outermembrane Protease & outermembrane antigens (Cytotoxins) antigens (Cytotoxins) Causing chronic inflammation Causing chronic inflammation of the inner lining of the stomach mucosa of the inner lining of the stomach mucosa

Helicobacter infectionHelicobacter infection

Diagnosis & TreatmentDiagnosis & Treatment Infection is most likely acquired by ingesting Infection is most likely acquired by ingesting

contaminated food, water , personal contact Causes contaminated food, water , personal contact Causes Re-infection is common..No vaccineRe-infection is common..No vaccine

Optimal growth..Special culture medium, 90%, Co2 Optimal growth..Special culture medium, 90%, Co2 37C.37C.

Urease breath testUrease breath test by drink a harmless liquid and in by drink a harmless liquid and in less than 1 hour, a sample of breath is tested.. Rapid less than 1 hour, a sample of breath is tested.. Rapid urease test for identification urease test for identification H. pylori H. pylori in gastric biopsy in gastric biopsy taken by endoscope or culture taken by endoscope or culture

Giemsa /silver stainGiemsa /silver stain.. histological biopsy specimens. .. histological biopsy specimens. Treatment: Metronidazole + Clarithromycin or Bismuth Treatment: Metronidazole + Clarithromycin or Bismuth

sulfate + Metronidazole + Amoxicillin + H2 Blockers..sulfate + Metronidazole + Amoxicillin + H2 Blockers..

Vibrios-1Vibrios-1

VibriosVibrios are Gram-negative straight or curved rods, are Gram-negative straight or curved rods, oxidase-positive, motile.. single polar oxidase-positive, motile.. single polar flagellum ..widely distribute in sea water ..2-3% NaCl.. flagellum ..widely distribute in sea water ..2-3% NaCl..

Classical Classical V. choleraeV. cholerae (serotypes 01, 0139).. Cause (serotypes 01, 0139).. Cause Epidemic- Pandemic Cholera.. Noninvasive.. Affecting Epidemic- Pandemic Cholera.. Noninvasive.. Affecting small intestine through secretion of an small intestine through secretion of an Enterotoxin- Enterotoxin- Heat-labile /Cholera ToxinHeat-labile /Cholera Toxin... . Increasing cAMPIncreasing cAMP.. ..

Incub. 8-24hIncub. 8-24h..Severe watery diarrhea, dehydration, ..Severe watery diarrhea, dehydration, shock, acidosis, death within 24 h.. Cause Only shock, acidosis, death within 24 h.. Cause Only Human Infection.Human Infection.

Partial immunity developed following infection.. Partial immunity developed following infection.. Specific developed antitoxin antibodies in intestine last Specific developed antitoxin antibodies in intestine last for 1-year ..Oral Vaccine used in endemic areas.. for 1-year ..Oral Vaccine used in endemic areas.. prevent re-infection up to 50%prevent re-infection up to 50%

Vibrios-2Vibrios-2 Non-01 Non-01 V. choleraeV. cholerae.. .. Less virulentLess virulent.. .. watery diarrhea watery diarrhea

due to due to CytotoxinsCytotoxins..found in water with ..found in water with o-1 V.cholerae o-1 V.cholerae V. parahaemolyticusV. parahaemolyticus.. .. Halophilic VibrioHalophilic Vibrio.. .. CytotoxinsCytotoxins Raw fish.. Swimming..Raw fish.. Swimming.. GastroenteritisGastroenteritis.. .. RareRare Sepsis, Sepsis,

Wound infection.. Contaminated fish Wound infection.. Contaminated fish * * Lab Diagnosis:Lab Diagnosis: Stool culture.. TCBS, Biochemical & Stool culture.. TCBS, Biochemical &

serotyping confirmation.serotyping confirmation. * * Treatment:Treatment: Oral re-hydration is the main treatment.. Oral re-hydration is the main treatment..

Replacement of fluid loss.. Water & Electrolytes.. Replacement of fluid loss.. Water & Electrolytes.. doxycycline, cotrimoxazole (children), ciprofloxacindoxycycline, cotrimoxazole (children), ciprofloxacin

PreventionPrevention:: Safe water & Food.. Early detection of Safe water & Food.. Early detection of

positive infected cases prevent outbreak of cholera in positive infected cases prevent outbreak of cholera in community..No Healthy carriers. community..No Healthy carriers.

Foodborne Toxigenic Bacteria-1Foodborne Toxigenic Bacteria-1

Staphylococcus aureusStaphylococcus aureus strains associated with strains associated with particular bacteriophage types can produce a particular bacteriophage types can produce a Heat-Heat-stable enterotoxinstable enterotoxin in food ( 20 minutes 100C), in food ( 20 minutes 100C), Absorbed from small Intestine.. Blood, CNSAbsorbed from small Intestine.. Blood, CNS

Staphylococcal food poisoningStaphylococcal food poisoning is commonly is commonly associated with salty foods, cream cakes, grounded associated with salty foods, cream cakes, grounded meat.. Fresh dairy products.. White chesses meat.. Fresh dairy products.. White chesses

Main SymptomsMain Symptoms.. Mostly Vomiting.. starts between .. Mostly Vomiting.. starts between 30 30 minutes and 6 hoursminutes and 6 hours following the consumption of the following the consumption of the contaminated food.. contaminated food.. No Fever and rarely DiarrheaNo Fever and rarely Diarrhea.. .. One day.. Self-Limited.One day.. Self-Limited.

Foodborne Toxigenic Bacteria-2Foodborne Toxigenic Bacteria-2 Bacillus cereusBacillus cereus.. .. G+ve Aerobic Spore-Forming G+ve Aerobic Spore-Forming

BacilliBacilli .. ..Common in NatureCommon in Nature.... Spores survive boiling and Spores survive boiling and cooling in Food.. Various cooling in Food.. Various Enterotoxins Enterotoxins produced during produced during bacilli sporulation either in bacilli sporulation either in Food or IntestineFood or Intestine.. .. Associated with Associated with two main gastrointestinal symptoms. two main gastrointestinal symptoms.

1-Intoxication 1-Intoxication .. Heat-stable .. Heat-stable EmeticEmetic EnterotoxinsEnterotoxins ..Typically developed within ..Typically developed within 24 hours24 hours of of eating contaminated fried rice.. Meat.. last for few eating contaminated fried rice.. Meat.. last for few hours without diarrhea and fever. hours without diarrhea and fever.

2- Diarrheal Toxins2- Diarrheal Toxins ..watery mild diarrhea.. No Fever ..watery mild diarrhea.. No Fever or Vomiting.or Vomiting.

3- Both Types of toxins may produce by certain 3- Both Types of toxins may produce by certain B. B. cereus strainscereus strains.. Mostly outbreaks in family, schools.. .. Mostly outbreaks in family, schools.. Commonly associated with Chinese food.. fried Rice Commonly associated with Chinese food.. fried Rice

Foodborne Toxigenic Bacteria-3Foodborne Toxigenic Bacteria-3

Clostridium perfringensClostridium perfringens.. .. G+ve G+ve Anaerobic Spore-Anaerobic Spore-FormingForming .. .. Widely distributed in the environment.. Widely distributed in the environment.. Common Intestines of humans and animals.. Produce Common Intestines of humans and animals.. Produce Various Various Enterotoxins, Cytotoxins, EnzymesEnterotoxins, Cytotoxins, Enzymes

C. C. perfringensperfringens toxin-type Atoxin-type A .. .. Food-poisoningFood-poisoning.. .. Incubation Period..8-24 Hrs.. Diarrhea.. Nausea.. Incubation Period..8-24 Hrs.. Diarrhea.. Nausea.. Abdominal Pain.. Vomiting.. No Fever.. Mostly Self-Abdominal Pain.. Vomiting.. No Fever.. Mostly Self-limited.. 1-2 Days.. No Antibiotic treatment limited.. 1-2 Days.. No Antibiotic treatment

C. perfringens C. perfringens toxin-Type Ctoxin-Type C.. Released following .. Released following multiplication in intestine.. Sever Diarrheamultiplication in intestine.. Sever Diarrhea.. .. No No vomiting.. vomiting.. Necrotizing EnteritisNecrotizing Enteritis.. Rare Sepsis.. Can be .. Rare Sepsis.. Can be fatal in certain Conditions.. Antibiotic treatment fatal in certain Conditions.. Antibiotic treatment

Detection toxin in blood.. Food specimens.Detection toxin in blood.. Food specimens.

Clostridium difficileClostridium difficile Anaerobic, spore-forming Gram+ve; Part of normal Anaerobic, spore-forming Gram+ve; Part of normal

intestinal flora (5-20%).. Rapidly increased and intestinal flora (5-20%).. Rapidly increased and become danger following become danger following antibiotic treatment antibiotic treatment for more for more than 1 week.. with all wide-spectrum peniciilins.. than 1 week.. with all wide-spectrum peniciilins.. clindamycin cephalosporins.. Often among clindamycin cephalosporins.. Often among hospitalized patients.. Compromised ..hospitalized patients.. Compromised ..Antibiotic-Antibiotic-associated enterocolitisassociated enterocolitis ..nosocomial infection. ..nosocomial infection.

Produce two exotoxins types A,B.. Bloody diarrhea.. Produce two exotoxins types A,B.. Bloody diarrhea.. Pseudomembranous colitisPseudomembranous colitis.. .. Discontinue potentialDiscontinue potential causative antibioticscausative antibiotics.... use oral metronidazole or use oral metronidazole or vancomycin.. to stop disease complication. vancomycin.. to stop disease complication.

Foodborne Toxigenic Bacteria-4Foodborne Toxigenic Bacteria-4

Clostridium botulinumClostridium botulinum G+veG+ve Anaerobic Spore-Anaerobic Spore-FormingForming ..Botulism.. Food-Intoxication.. ..Botulism.. Food-Intoxication.. Incubation1-24 Incubation1-24 hh

Consumption improperly or inadequately processed Consumption improperly or inadequately processed canned food.. Spores.. Vegetative cells.. Release canned food.. Spores.. Vegetative cells.. Release highly potent highly potent heat-stable neurotoxin heat-stable neurotoxin ( A-G types).. ( A-G types).. inactivation 30min boiling. inactivation 30min boiling.

Botulinum toxin Botulinum toxin binds to binds to presynaptic nerve ending of presynaptic nerve ending of peripheral nervous system & cranial nerves..peripheral nervous system & cranial nerves.. Inhibits Inhibits acetylcholine release acetylcholine release .. Flaccid paralysis, Respiratory .. Flaccid paralysis, Respiratory or Cardiac failure.. Death.. Early Specific Antitoxin or Cardiac failure.. Death.. Early Specific Antitoxin Treatment may help.. No AntibioticsTreatment may help.. No Antibiotics

Other Bacteria speciesOther Bacteria species YersiniaYersinia enterocoliticaenterocolitica ..Gram-ve bacilli, common in ..Gram-ve bacilli, common in

cold water, pigs.. Less in dogs, cats, other animals.. cold water, pigs.. Less in dogs, cats, other animals.. the bacteria are most likely to be found on the tonsils the bacteria are most likely to be found on the tonsils and intestines..Contaminate often and intestines..Contaminate often dairy products dairy products infect infect mostly children younger< 1 year & compromised host .mostly children younger< 1 year & compromised host .

Common symptoms in children are Common symptoms in children are fever, abdominal fever, abdominal pain, bloody diarrheapain, bloody diarrhea.. complications such as skin .. complications such as skin rash, joint pains, or blood sepsis can occur in rash, joint pains, or blood sepsis can occur in compromised patients.compromised patients.

AeromonasAeromonas species species.. Gram-ve bacilli, common in .. Gram-ve bacilli, common in natural water sources.. a significant cause of bacterial natural water sources.. a significant cause of bacterial gastroenteritis ..cytotoxins .. young children.. Diarrhea, gastroenteritis ..cytotoxins .. young children.. Diarrhea, dehydration.. Less Fever, vomiting.dehydration.. Less Fever, vomiting.