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

Prof .Dr. Asem ShehabiProf .Dr. Asem Shehabi

Faculty of MedicineFaculty of Medicine

University of JordanUniversity of Jordan

IntroductionIntroduction Worldwide, At least one Worldwide, At least one billion of children & adults billion of children & adults

are affected by diarrhea each year. In developing are affected by diarrhea each year. In developing countries, where general sanitation is low, epidemics countries, where general sanitation is low, epidemics of bacterial gastroenteritis cause high of bacterial gastroenteritis cause high morbidity & morbidity & mortalitymortality among infants & Jung children . among infants & Jung children .

The commonest clinical manifestations of bacterial The commonest clinical manifestations of bacterial gastrointestinal infections are diarrhea, vomiting , gastrointestinal infections are diarrhea, vomiting , abdominal pain, fever. abdominal pain, fever.

Bacterial intestinal infection..followed Bacterial intestinal infection..followed water/Food water/Food contaminationcontamination.. incubation period .. incubation period 8-24 hrs .. 8-24 hrs .. rarely rarely involve other organs and systems.. involve other organs and systems.. Recovery Recovery 2 days 2 days

Watery diarrheaWatery diarrhea..involved small and large intestines..involved small and large intestines Bloody-diarrhea Bloody-diarrhea (Dysentery(Dysentery ) mostly Large intestine ) mostly Large intestine EnterocolitisEnterocolitis inflammation of both inflammation of both small & large small & large

intestines, intestines, bacteria & toxin..watery bloody diarrheabacteria & toxin..watery bloody diarrhea

Bacteria Food poisoningBacteria Food poisoning Bacterial food poisoning Bacterial food poisoning ..Food intoxication is ..Food intoxication is

another common cause GI illness associated with the another common cause GI illness associated with the presence of a pre-formed toxin in food released by presence of a pre-formed toxin in food released by Toxigenic bacteriaToxigenic bacteria.. Mostly associated first with .. Mostly associated first with vomiting & later watery diarheavomiting & later watery diarhea.. No fever.. Short .. No fever.. Short incubation period..2-8 hoursincubation period..2-8 hours

In many cases the toxin may be produced in the food In many cases the toxin may be produced in the food by bacterial growth during storage or preparation.. by bacterial growth during storage or preparation.. hand or environmental contamination. hand or environmental contamination.

Common Gram-ve: Common Gram-ve: Salmonella spp., Salmonella spp., Various types Various types diarrheagenicdiarrheagenic E. coli strains, Campylobacter spp., V. E. coli strains, Campylobacter spp., V. cholerae, Listeria & Aeromonas spp. cholerae, Listeria & Aeromonas spp.

Gram-positive : Gram-positive : Cl. perfingens, Cl.difficile, Cl. perfingens, Cl.difficile, Staphylococcus aureus, Bacillus cereusStaphylococcus aureus, Bacillus cereus

Salmonella GroupSalmonella Group

Salmonellae group:Salmonellae group: Gram-negative bacilli, Facultative Gram-negative bacilli, Facultative anaerobes.. By current classification there is only one anaerobes.. By current classification there is only one major species of Salmonella: major species of Salmonella: S. entericaS. enterica.. but there are .. but there are numerous serovars .. about 2000 types numerous serovars .. about 2000 types

A serovar is classified by presence of a specific set of A serovar is classified by presence of a specific set of O (cell wall) ,H (flagellar), Vi (virulence) antigensO (cell wall) ,H (flagellar), Vi (virulence) antigens. .

Human Salmonellosis Human Salmonellosis is divided into: is divided into:

1- 1- Enteric Fever Salmonellas Enteric Fever Salmonellas /Typhoid fever/Typhoid fever.. infect only .. infect only humans caused byhumans caused by enterica subtypeTyphi & Paratyhi enterica subtypeTyphi & Paratyhi A, BA, B, , C..C.. Cause severe human systemic diseases.. Cause severe human systemic diseases.. following invading GI with few salmonella cells..often following invading GI with few salmonella cells..often through contaminated water..Less fresh Food, rarely by through contaminated water..Less fresh Food, rarely by direct contact. Incubation period direct contact. Incubation period 1-3 weeks. 1-3 weeks.

Typhoid fever-2Typhoid fever-2 Typhoid fever is a severe Typhoid fever is a severe multisystemic illnessmultisystemic illness.. ..

Salmonella invade & multiply within Salmonella invade & multiply within intestinal mucosaintestinal mucosa .. .. Peyer patchesPeyer patches.. Enter intestinal lymphoid follicles.. .. Enter intestinal lymphoid follicles.. Macrophages carry cells to Reticuloendothelial Macrophages carry cells to Reticuloendothelial system ..Causing Lymphoid hyperplasia & hypertrophy system ..Causing Lymphoid hyperplasia & hypertrophy later spread to later spread to Blood, liver and other internal organsBlood, liver and other internal organs.. ..

Typhoid Fever Typhoid Fever is characterized by the prolonged & high is characterized by the prolonged & high fever, headache, malaise, liver & spleen fever, headache, malaise, liver & spleen enlargement ..Skin rash (Rose spots)..Mostly watery- enlargement ..Skin rash (Rose spots)..Mostly watery- bloody diarrhoea /constipation at the beginning.bloody diarrhoea /constipation at the beginning. Pathogenicity: Pathogenicity: Virulence factors.. Proteinous capsule (S. Virulence factors.. Proteinous capsule (S. typhi Vi antigen), Cell wall Lipopolysaccharides, release typhi Vi antigen), Cell wall Lipopolysaccharides, release specific cytotoxin. specific cytotoxin.

Salmonella-TyphoidSalmonella-Typhoid Fever -2Fever -2

Following necrosis of liver, spleen, gallbladder. lymph Following necrosis of liver, spleen, gallbladder. lymph tissues, peyer patches.. Salmonella re-enter intestinal tissues, peyer patches.. Salmonella re-enter intestinal tract.. causing severe intestinal inflammation, Bloody tract.. causing severe intestinal inflammation, Bloody diarrhea, enterocolitis, diarrhea, enterocolitis, intestinal perforation & toxic intestinal perforation & toxic shookshook. 10-30% of patients might died without . 10-30% of patients might died without antibiotic treatment.antibiotic treatment.

Tyhoid fever Tyhoid fever may be associated with meningitis, may be associated with meningitis, mostly in children & immune deficiency. Few mostly in children & immune deficiency. Few percentage complications presented as pneumonia, percentage complications presented as pneumonia, endocarditis, osteomyelitis, septic arthritis, hepatic endocarditis, osteomyelitis, septic arthritis, hepatic abscesses, soft tissue abscesses in any body part.abscesses, soft tissue abscesses in any body part.

Typhoid fever-3Typhoid fever-3 Up to 5% of infected persons become Up to 5% of infected persons become healthy healthy

carrierscarriers later..Females more than Males..Infection later..Females more than Males..Infection becomes chronic.. Carry the bacteria in their becomes chronic.. Carry the bacteria in their GallbladderGallbladder.. Less in .. Less in Peyer patchesPeyer patches.. execrate .. execrate bacteria in their feces long live. bacteria in their feces long live.

Healthy carriers maintain the cycle of Typhoid disease Healthy carriers maintain the cycle of Typhoid disease in the community. in the community.

Host responded to infection by production of specific Host responded to infection by production of specific antibodies antibodies ((Anti-O & anti-HAnti-O & anti-H) ) which can be detected which can be detected after 2 weeks.. These antibodies might prevent after 2 weeks.. These antibodies might prevent developing of severe complications and death.developing of severe complications and death.

Process of Tyhoidal Salmonella Process of Tyhoidal Salmonella InfectionInfection

Lab DiagnosisLab Diagnosis Definitive diagnosis Typhoid Fever: Definitive diagnosis Typhoid Fever: Requires culture & Requires culture &

isolation of the organism from isolation of the organism from blood, Feces, CSF, blood, Feces, CSF, Urine Urine Acute- sub-acute cases.Acute- sub-acute cases.

Chronic casesChronic cases.. bone marrow, Gallbladder.. .. bone marrow, Gallbladder.. Healthy Healthy CarriersCarriers.. execrate occasionally bacteria in stool... execrate occasionally bacteria in stool.

Presence S. typhi only in stool without clinical disease Presence S. typhi only in stool without clinical disease indicates often a carriage state. indicates often a carriage state.

Selective culture media: Selective culture media: S-S agar, Heckton-enteric S-S agar, Heckton-enteric agar… Lactose non-fermenter bacteria growthagar… Lactose non-fermenter bacteria growth

Serological test: Serological test: Widal test is used for the diagnosis Widal test is used for the diagnosis of Typhoid fever.. measures levels of antibodies of Typhoid fever.. measures levels of antibodies against (O, H ) antigens.. against (O, H ) antigens.. Titer > 160Titer > 160 or or rising titers.. rising titers.. positive (Vi ) antigen indicate positive (Vi ) antigen indicate S. typhiS. typhi.. acute infection... acute infection.

Treatment & PreventionTreatment & Prevention

Antibiotic therapy Antibiotic therapy is essential and should begin is essential and should begin empirically if clinical evidence of infection is strong.. empirically if clinical evidence of infection is strong.. Ciprofloxacin 4 weeks.. Ceftriaxone for pregnant Ciprofloxacin 4 weeks.. Ceftriaxone for pregnant women & Children..women & Children.. Chloramphenicol & Amoxacillin, Chloramphenicol & Amoxacillin, Augmentin Augmentin is currently less used due to resistance. is currently less used due to resistance.

Fatality is high without antibiotic treatmentFatality is high without antibiotic treatment Most developing countries is endemic with Tyhoidal Most developing countries is endemic with Tyhoidal

Salmonella.. Public health measures concentrate to Salmonella.. Public health measures concentrate to control safe drinking water, proper sewage disposal. control safe drinking water, proper sewage disposal. Detection of human carries.. Education programs on Detection of human carries.. Education programs on food hygiene. food hygiene.

Oral live attenuated Tyhoid vaccine or injectable Oral live attenuated Tyhoid vaccine or injectable vi-vi-capsular polysaccharide vaccinecapsular polysaccharide vaccine is used for short is used for short protection for army personals in endemic regionprotection for army personals in endemic region. .

Gastroenteritis/ Food-Poisoning Gastroenteritis/ Food-Poisoning Salmonellas-2Salmonellas-2

S.S. enterica var Typhimurium and S. enterica var enterica var Typhimurium and S. enterica var EnteritidisEnteritidis .. are most common serotypes of GI .. are most common serotypes of GI Salmonellosis in humans, Birds/chicken, animals, Salmonellosis in humans, Birds/chicken, animals, Rats. Each year Million food-borne cases worldwide, Rats. Each year Million food-borne cases worldwide, single & outbreaks..Contaminate commonly human single & outbreaks..Contaminate commonly human fresh prepared food..fresh prepared food..Grounded meat & Eggs.Grounded meat & Eggs.

After Salmonella ingestion.. invade epithelial cells After Salmonella ingestion.. invade epithelial cells small intestine, release enterotoxin/ cytotoxin causes small intestine, release enterotoxin/ cytotoxin causes inflammatory responseinflammatory response, , stimulates stimulates cAMPcAMP.. results in .. results in intense & prolonged hypersecretion chlorides ions & intense & prolonged hypersecretion chlorides ions & water, inhibiting the reabsorption of sodium water, inhibiting the reabsorption of sodium Incubation Incubation 8-24 hrs8-24 hrs, , Watery-bloody diarrhea, abdominal pain, fever.. Watery-bloody diarrhea, abdominal pain, fever.. Less vomiting. Less vomiting. Complications: Complications: septicemia, meningitis observed septicemia, meningitis observed mostly in neonates, infant, immune-suppressed patients. mostly in neonates, infant, immune-suppressed patients.

Intestinal Salmonella InfectionsIntestinal Salmonella Infections

GastroenteritisSalmonellas-2GastroenteritisSalmonellas-2 No antimicrobial drugs treatmentNo antimicrobial drugs treatment.. For normal .. For normal

healthy persons.. healthy persons.. Only RehydrationOnly Rehydration.. Antimicrobial .. Antimicrobial drugs should be given for drugs should be given for infants & immuno-infants & immuno-suppressed patients.suppressed patients.

Rare & Short human healthy carriers in intestine.. Rare & Short human healthy carriers in intestine.. Clinical cases execrate salmonella for few days-weeks Clinical cases execrate salmonella for few days-weeks in feces-short-period healthy carrier.in feces-short-period healthy carrier.

Stool cultureStool culture in S-S agar, Heckton-enteric agar in S-S agar, Heckton-enteric agar Prevention hand-food contamination.. often Chicken Prevention hand-food contamination.. often Chicken

eggs & meat & Dairy products, mayonnaise eggs & meat & Dairy products, mayonnaise Widal test is not significant in diagnosis of infection. Widal test is not significant in diagnosis of infection.

No human vaccine is availableNo human vaccine is available..chicken vaccine ..chicken vaccine

Shigellosis-1Shigellosis-1 Shigella spp Shigella spp continue to be a major health problem continue to be a major health problem

worldwide, causing an estimated 1 million deaths and worldwide, causing an estimated 1 million deaths and about 150 million cases of diarrhea annually. about 150 million cases of diarrhea annually. Shigella Shigella are Gram-negative, Lactose-ve bacilli.. Facultative are Gram-negative, Lactose-ve bacilli.. Facultative Anaerobes.. Highly susceptible to dryness.. Acidity.. Anaerobes.. Highly susceptible to dryness.. Acidity.. killed within 1 hour in stool. killed within 1 hour in stool. There are 4 species of There are 4 species of Shigella:Shigella: S. dysenteriae, S. sonnei , S.boydii, S. S. dysenteriae, S. sonnei , S.boydii, S. flexneri flexneri

ShigellaeShigellae cells invade, multiply in mucosa of large cells invade, multiply in mucosa of large intestine, cause swelling & necrosis intestinal wall due intestine, cause swelling & necrosis intestinal wall due to to cytotoxin & endotoxincytotoxin & endotoxin.. Watery-bloody diarrhea, .. Watery-bloody diarrhea, severe abdominal cramps, high fever & nausea.. less severe abdominal cramps, high fever & nausea.. less vomitingvomiting, feces , feces contains numerous WBCs & mucus,contains numerous WBCs & mucus, Incub period within 24 hrs. Incub period within 24 hrs.

Shigellosis-2Shigellosis-2 Clinical disease Clinical disease ranges from mild diarrhea to ranges from mild diarrhea to

dysentery..few days, Most deaths occur in yung dysentery..few days, Most deaths occur in yung children / elderly persons due to dehydration & blood children / elderly persons due to dehydration & blood loss. Only Human infection. loss. Only Human infection. highly infectious & highly infectious & communicable communicable ..Person to person contact, water, fresh ..Person to person contact, water, fresh green leaf vegetables. green leaf vegetables.

DysenteriaeDysenteriae is the classic cause of bacillary is the classic cause of bacillary dysentery ..dysentery ..Sh. Dysenteriae:Sh. Dysenteriae: severe necrosis, muco-severe necrosis, muco-purulent bloody diarrhoea, severe abdominal pain, purulent bloody diarrhoea, severe abdominal pain, high fever..more bloody diarrhea & dehydration high fever..more bloody diarrhea & dehydration

Release heat-labile Release heat-labile Shiga enterotoxin Shiga enterotoxin (neurotoxin).. (neurotoxin).. affects small intestine.. carried to blood, CNS.. causes affects small intestine.. carried to blood, CNS.. causes mild-severe mild-severe Meningism & CommaMeningism & Comma.. Few cases .. Few cases hemolytic-uremic syndrome. Death rate is high in hemolytic-uremic syndrome. Death rate is high in patients not treated..septicemia is rare .patients not treated..septicemia is rare .

Diagnosis & treatmentDiagnosis & treatment

Acute Shigella case: Direct stool examination for Acute Shigella case: Direct stool examination for presence of numerous presence of numerous WBCs and blood cellsWBCs and blood cells

Direct rectal swab.. or rapid stool culture of feces on Direct rectal swab.. or rapid stool culture of feces on S-S agar, Heckton-enteric agarS-S agar, Heckton-enteric agar.. Shigella Isolation & .. Shigella Isolation & conformation by biochemical tests and serotyping. conformation by biochemical tests and serotyping.

Antibiotics is recommended.. Antibiotics is recommended.. ciprofloxacin, ciprofloxacin, doxycycline, cotrimoxazoledoxycycline, cotrimoxazole .. Shorten the diarrhea .. Shorten the diarrhea duration.... Rehydration is important but not enough.. duration.... Rehydration is important but not enough..

Most person develop Most person develop non-protective specific non-protective specific antibodies.. antibodies.. No healthy carrier stage No healthy carrier stage ..Prevention ..Prevention concentrate on hygiene control of water, milk, fresh concentrate on hygiene control of water, milk, fresh food..Vaccine used in wars and endemic area. food..Vaccine used in wars and endemic area.

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 stableHeat stable or or Heat -labile enterotoxinsHeat -labile enterotoxins (plasmid borne) or both ( (plasmid borne) or both ( ST+ ST+ LTLT).. fimbrial adhesins attached to enterocytes of the ).. fimbrial adhesins attached to enterocytes of the small intestine epithelium.small intestine epithelium.

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

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

AdhesionsAdhesions byby Fimbriae CFA I & CFA IIFimbriae CFA I & CFA II

Diarrheagenic Diarrheagenic E. coli-2E. coli-2

ETECETEC strains strains are frquent & important cause of are frquent & important cause of diarrhea in infants/very young children & common diarrhea in infants/very young children & common cause of cause of Traveler’s diarrhea Traveler’s diarrhea in developed countries.in developed countries.

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

Self- limited with oral rehydration, Antibiotics are rarely Self- limited with oral rehydration, Antibiotics are rarely needed,needed, developdevelop intestinal immunity.intestinal immunity.

2-2- Entero-haemorrhagic Entero-haemorrhagic E. coli E. coli (EHEC) (EHEC) Shiga-like Shiga-like toxin toxin / Vero-toxigen..Many serotype strains, commonly / Vero-toxigen..Many serotype strains, commonly O157: H7..O157: H7.. , common in intestines of animals/ cows.. , common in intestines of animals/ cows.. contamination milk & ground beef meat.. causes contamination milk & ground beef meat.. causes outbreaks of gastroenteritis & later outbreaks of gastroenteritis & later Haemolytic Haemolytic Uraemic SyndromeUraemic Syndrome (HUS). (HUS).

Diarrheagenic Diarrheagenic E. coli-3E. coli-3 Complications:Complications: Severe inflammation & ulceration colon, Severe inflammation & ulceration colon,

Bloody-purulent diarrhea Bloody-purulent diarrhea Haemorrhagic colitisHaemorrhagic colitis.. .. If toxin If toxin reached blood & reach Kidneys results reached blood & reach Kidneys results HUS HUS (HUS).. More (HUS).. More severe in children/old patients.. Release Blood+ Protein in severe in children/old patients.. Release Blood+ Protein in urine.. Kidney failure highly fatal. urine.. Kidney failure highly fatal.

Prevention is better than treatment with antimicrobials.Prevention is better than treatment with antimicrobials. 3-Entero-pathogenic E.coli3-Entero-pathogenic E.coli (EPEC).. K, (EPEC).. K, LPS LPS Antigens Antigens

adherence to GI epithelium & distortion.. numerous adherence to GI epithelium & distortion.. numerous serotypes.. Common infection in neonates.. Outbreaks serotypes.. Common infection in neonates.. Outbreaks watery diarrhea & vomiting in infant nurseries aged less 6 watery diarrhea & vomiting in infant nurseries aged less 6 months.. Commonly chronic diarrhea. months.. Commonly chronic diarrhea.

4-Entero-invasive E.coli4-Entero-invasive E.coli ( (EIEC).. Similar to Shigella causes EIEC).. Similar to Shigella causes bloody diarrhea bloody diarrhea ,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 common and severe in children.Affect all ages..more common and severe 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 commonly present in the virulent E. coli strains are commonly present in the feces. feces.

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

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

No vaccines are available for all diarrheagenic E.coli No vaccines are available for all diarrheagenic E.coli

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

shape.. Bipolar flagella.shape.. Bipolar flagella.. . Motile.. Isolation on Motile.. Isolation on selective special selective special agar at 42 Cagar 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, fresh Food & .. Contaminate easily Meat, Dairy products, fresh Food & Direct contact with animals.. Common cause of diarrhea in Direct contact with animals.. Common cause of diarrhea in Western countries..Less in Arab countries.Western countries..Less in Arab countries.

Campylobacter jejuni:Campylobacter jejuni: ReleaseRelease Endotoxin & various Endotoxin & various enterotoxin/cytotoxinsenterotoxin/cytotoxins.. .. Acute enteritis,Acute enteritis, Bloody diarrheaBloody diarrhea, few , few days, Infants, children > adults, Elderly. Rare septicemia, days, Infants, children > adults, Elderly. Rare septicemia, Reactive arthritis followed chronic diarrhea. Reactive arthritis followed chronic diarrhea.

Infection is mostly self-limited without treatment. Prolong Infection is mostly self-limited without treatment. Prolong carriage associated with immunodeficiency. carriage associated with immunodeficiency.

C. fetusC. fetus.. .. Less common human diarrhea.. Commonly causes Less common human diarrhea.. Commonly causes sepsis & abortion in animals. sepsis & abortion in animals. Culture is more significant then Culture is more significant then serological test in diagnosis clinical chronic cases.serological test in diagnosis clinical chronic cases.

Treatment: Treatment: Macrolides/Azithromycin, Ciprofloxacin, AmpicillinMacrolides/Azithromycin, Ciprofloxacin, Ampicillin

Campylobacter- Campylobacter- Vibrio choleraVibrio cholera

Helicobacter pyloriHelicobacter pylori Microaerophlic growth.. Gram-ve spiral shape, motile, Microaerophlic growth.. Gram-ve spiral shape, motile,

polar 4-6 flagella .. produces potent polar 4-6 flagella .. produces potent urease,urease, neutralize neutralize stomach acidity, allow colonizing mucus overlaying stomach acidity, allow colonizing mucus overlaying gastric mucosa mainly gastric antrum. gastric mucosa mainly gastric antrum.

H. pylori H. pylori colonize stomach of colonize stomach of 30%-9030%-90% % of world’s of world’s population according their age.. Mostly without signs population according their age.. Mostly without signs or symptoms and may not cause any disease. or symptoms and may not cause any disease.

Pathogenicity:Pathogenicity: Protease, outermembrane antigens & Protease, outermembrane antigens & CytotoxinsCytotoxins causing chronic inflammation of the inner causing chronic inflammation of the inner lining of the stomach mucosa.. Gastritis, Peptic lining of the stomach mucosa.. Gastritis, Peptic /dudenal ulcers..about 2 % infected persons./dudenal ulcers..about 2 % infected persons.

H. pylori H. pylori discovered 1983 as cause of chronic discovered 1983 as cause of chronic gastritis.. Complications Gastric lymphoma, Stomach gastritis.. Complications Gastric lymphoma, Stomach cancercancer in infected persons over a long period. in infected persons over a long period.

Helicobacter infectionHelicobacter infection

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

water, personal/family contact. Re-infection is water, personal/family contact. Re-infection is common. Optimal growth..selective culture medium common. Optimal growth..selective culture medium with 90% Cowith 90% Co22 , 42 C, 3-5 days. , 42 C, 3-5 days.

Diagnoses: Diagnoses: A) clinically by A) clinically by Urea breath testUrea breath test , using , using urea capsule labeled with active carbon detects urea capsule labeled with active carbon detects urease activity in stomach by splitting urea into urease activity in stomach by splitting urea into CoCo22 & &

AmmoniaAmmonia. B) A rapid urease test for identification . B) A rapid urease test for identification H. H. pylori pylori in gastric biopsy taken by endoscope or culture in gastric biopsy taken by endoscope or culture

Giemsa /silver stainGiemsa /silver stain by histological examination. by histological examination. Serological antibodies test is less significantSerological antibodies test is less significant. .

Treatment: Treatment: Metronidazole + Clarithromycin / Bismuth Metronidazole + Clarithromycin / Bismuth sulfate or Metronidazole + Amoxicillin + Hsulfate or Metronidazole + Amoxicillin + H22 Blockers.. Blockers..

Vibrios-1Vibrios-1 Vibrio Vibrio group group is Gram-negative straight or curved is Gram-negative straight or curved

rods, oxidase-positive, motile, single polar flagellum.. rods, oxidase-positive, motile, single polar flagellum.. Common in sea water-human cycle. Common in sea water-human cycle.

Classical Classical V. choleraeV. cholerae (serotypes 01), 0139 El-tor type.. (serotypes 01), 0139 El-tor type.. Infect only human.. Infect only human.. Cause Epidemic/Pandemic Cause Epidemic/Pandemic Outbreaks.. Spread from India subcontinent. Outbreaks.. Spread from India subcontinent.

Noninvasive.. affecting small intestine through Noninvasive.. affecting small intestine through Heat-Heat-labile Cholera Toxinlabile Cholera Toxin (A and B subunits) (A and B subunits) B-unit binds B-unit binds to Gangliosies release A-unit.. to Gangliosies release A-unit.. Increasing cAMPIncreasing cAMP causing outpouring large amount water, Nacausing outpouring large amount water, Na++, K, K++ Cl Cl- - , , HCOHCO-- . . Incub. 8-24hIncub. 8-24h..Severe watery diarrhea (1-3 ..Severe watery diarrhea (1-3 Liters) ,vomiting & cramps, rapid dehydration, shock, Liters) ,vomiting & cramps, rapid dehydration, shock, blood acidosis, renal failure.. death within 24 h if blood acidosis, renal failure.. death within 24 h if patient not received replacement of fluid loss .patient not received replacement of fluid loss .

Partial intestinal immunity.. antitoxin antibodies Partial intestinal immunity.. antitoxin antibodies last for last for 1-year, Oral vaccine is effective for short period. 1-year, Oral vaccine is effective for short period.

Vibrios-2Vibrios-2 Non-01 Non-01 V. choleraeV. cholerae.. .. found in water along with found in water along with 0-1 0-1

V.cholerae V.cholerae Less virulentLess virulent.. .. watery diarrhea similar to watery diarrhea similar to classical cholera due to release classical cholera due to release cytotoxins.cytotoxins.

V. parahaemolyticusV. parahaemolyticus.. .. Halophilic VibrioHalophilic Vibrio.. .. CytotoxinsCytotoxins Raw fish.. Swimming..Raw fish.. Swimming.. GastroenteritisGastroenteritis.. .. MayMay cause cause

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

serotyping confirmation with specific cholera antisera.serotyping confirmation with specific cholera antisera. * * Treatment:Treatment: Oral rehydration is the main treatment.. Oral rehydration is the main treatment..

Replacement of fluid loss..doxycycline, cotrimoxazole Replacement of fluid loss..doxycycline, cotrimoxazole (children), ciprofloxacin reduce the Vibrios excretion (children), ciprofloxacin reduce the Vibrios excretion

** 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

specific bacteriophage types can produce several specific bacteriophage types can produce several Heat-stable protein exotoxins Heat-stable protein exotoxins in food ( 20 minutes in food ( 20 minutes 100C), Fast absorbed from small Intestine to Blood 100C), Fast absorbed from small Intestine to Blood stream & affects CNS. Staphylococcal food poisoning stream & affects CNS. Staphylococcal food poisoning is commonly associated with salty foods, cream is commonly associated with salty foods, cream cakes, grounded meat.. Fresh dairy products.. White cakes, grounded meat.. Fresh dairy products.. White chesses. chesses.

Main SymptomsMain Symptoms: : 30 minutes-6 hours30 minutes-6 hours following the following the consumption of the contaminated food.. vomiting, consumption of the contaminated food.. vomiting, nausea, stomach cramps.. rarely watery diarrhea.. No nausea, stomach cramps.. rarely watery diarrhea.. No fever & recovery within 1-2 days.. Self-limited.fever & recovery within 1-2 days.. Self-limited.

Diagnoses: detection of Staph. toxins in eaten food.Diagnoses: detection of Staph. toxins in eaten food.

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

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

1-Intoxication 1-Intoxication .. Heat-Acid stable .. Heat-Acid stable Emetic Enterotoxins Emetic Enterotoxins .... Typically developed within Typically developed within 1-24 hours1-24 hours of eating of eating contaminated fried rice, meat.. Vomiting nausea, contaminated fried rice, meat.. Vomiting nausea, stomach cramps last for few hours without diarrhea & stomach cramps last for few hours without diarrhea & fever. fever. 2- Diarrheal Toxins/2- Diarrheal Toxins/ HLHL..watery mild diarrhea.. ..watery mild diarrhea.. No Fever or Vomiting..self-limiting within 1-3 days.No Fever or Vomiting..self-limiting within 1-3 days.

Both Types of toxins may produce from the same Both Types of toxins may produce from the same B. B. cereus straincereus strain.. 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 perfringens.. Clostridium perfringens.. G+ve Anaerobic Spore-G+ve 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 A toxin-type A ..released in Food at room ..released in Food at room temperature ..intoxication after temperature ..intoxication after 8-24 Hrs8-24 Hrs.. Diarrhea.. .. Diarrhea.. Nausea.. Abdominal Pain.. Rare vomiting.. No Fever.. Nausea.. Abdominal Pain.. Rare vomiting.. No Fever.. Mostly Self-limited.. 1-2 Days.. No Antibiotic treatment Mostly Self-limited.. 1-2 Days.. No Antibiotic treatment

C. perfringens C. perfringens toxin-Type Ctoxin-Type C.. Released following .. Released following multiplication in intestine.. severe watery-bloody multiplication in intestine.. severe watery-bloody diarrheadiarrhea.. .. Necrotizing EnteritisNecrotizing Enteritis.. No vomiting.. Rare .. No vomiting.. Rare sepsis.. can be fatal in certain conditions.. Antibiotic sepsis.. can be fatal in certain conditions.. Antibiotic treatment is recommended.treatment is recommended.

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

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

flora of neonates & infants.. Adults (5-20%).. Rapidly increased flora of neonates & infants.. Adults (5-20%).. Rapidly increased colonization in hospitalized patients & become active danger colonization in hospitalized patients & become active danger after after antibiotic treatment antibiotic treatment for more than 1 week.. with all wide-for more than 1 week.. with all wide-spectrum peniciilins, clindamycin cephalosporins.. Often spectrum peniciilins, clindamycin cephalosporins.. Often causes nosocomial infection among elderly, surgery & causes nosocomial infection among elderly, surgery & compromised patients.compromised patients.

Antibiotic-associated enterocolitisAntibiotic-associated enterocolitis developed by release developed by release 2 2 toxins types (enterotoxin A, cytotoxin B)toxins types (enterotoxin A, cytotoxin B) acting directly on acting directly on intestinal epithelial cells causing necrosis.. Bloody diarrhea.. intestinal epithelial cells causing necrosis.. Bloody diarrhea.. Increased rapidly within days to severe Increased rapidly within days to severe Pseudomembranous Pseudomembranous colitis.. colitis.. AnotherAnother new strain producing more potent binary toxin new strain producing more potent binary toxin

detected few years ago. detected few years ago. Treatment:Treatment: stop use potential stop use potential causative antibioticscausative antibiotics,, use metronidazole / vancomycin will use metronidazole / vancomycin will prevent disease complication. prevent disease complication.

Foodborne Toxigenic Bacteria-4Foodborne Toxigenic Bacteria-4 Clostridium botulinumClostridium botulinum G+veG+ve Anaerobic Spore-FormingAnaerobic Spore-Forming

..Botulism.. Food-Intoxication.. ..Botulism.. Food-Intoxication.. Incubation 1-24 hrs.Incubation 1-24 hrs. 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 ( A-G types).. heat-stable neurotoxin ( A-G types).. inactivation 30 min boiling.. Rare cases worldwide.inactivation 30 min boiling.. Rare cases worldwide.

Botulinum toxin Botulinum toxin binds to presynaptic nerve ending of binds to presynaptic nerve ending of peripheral nervous system & cranial nerves.. inhibits peripheral nervous system & cranial nerves.. 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 Diagnosis: clinical features ..Treatment may help.. No Diagnosis: clinical features ..Treatment may help.. No AntibioticsAntibiotics

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 fever, abdominal Common symptoms in children are fever, abdominal pain, bloody diarrhea & fever.. complications such as pain, bloody diarrhea & fever.. complications such as skin rash, joint pains, or blood sepsis can occur in skin 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 gastroenteritis in association with fish food ..cytotoxins in association with fish food ..cytotoxins .. young children.. watery diarrhea.. dehydration.. Less .. young children.. watery diarrhea.. dehydration.. Less Fever & vomiting.Fever & vomiting.