Signs Organism Symptoms Pathoger Clinical Features Vibrio cholerae Abrupt onset of iiquid alarmed in enc diarrhea Toxincauses hypersecretion in small area Needs prompt replacement of fluid intestine. Infective and electrolytes IV or orally, Stool cultures dose >10 organisms positive Use selective media Shigella species(mild ot onset of diarrhea: can hav cases) Dysentery Organisms invade epithelial cells; blood pus in stools, cramps, tenesmus, and lethargy mucus, and PMNs in mild and self-limiting. Restore fluids <organisms Shigella dysenteriae Produces cytotoxin and Severe bloody diarrhea in children in developing type 1(Shiga bloody countries; high fatality rate. Rare in the United Salmonella species Dysentery Superficial infection of Gradual or abrupt onset of diarrhea and low- gut, little invasion. grade fever. WBC in stool. Stool cultures are Infective dose >10 positive. No antimicrobials unless systemic organisms immuno-compromised. Prolonged carriage s frequent sidious onset of malaise, anorexia. Salmonella Typhi Enteric fever evades intestinal mucosa myalgias, and headache; high remittent Is pororyph/A and B and multiplies in macrophages in fever may have constipation or diarrhea. Hepatosplenomegaly in about 50% of patient, Diagnosis by culture of s typhi from
Signs and Clinical features Organism Symptoms iogel Yersinia enterocolitica Enteric fever stroenterris or Severe abdominal pain, diarrhea, fever; PMNS and blood in stool: polyarthritis, erythema Occasional bacteremia. nodosum, especially in children. Keep stool Toxin produced occasionally specimen at 4 C before culture Clostridium difficile Makes enterotoxin Abrupt onset of bloody diarhea and fever. Toxin (toxin A) and cytotoxin in stool. Patient typically received antibiotics (toxin B), which cause hea and epithelial cell necrosis Campylobacter jejuni Dysentery nvas,on of mucous membrane Toxin Fever, diarrhea; PMNs, and fresh blood in stools, production uncertain especially in children. Usually selfF-limited. special media needed for cultures at 42C
Lab diagnosis Shigella Dysenteria Stool culture Salmonella Typh Culture: blood. stool or urine Non-typhi groups of Culture: blood stool or urine Salmonella Yersinia enterocolitica .Stool or blood cultures ° colonscopy Vibrio cholerae .Dark field microscopy grows as fiat yellow colonies on selective media: thiosulfate-citrate-bile-salts sucrose agar Campylobacter jejuni .Microscopic exam of stool .Selective media with antibiotics at 42(c
Lab Diagnosis Salmonella Typhi Culture: blood,stool or urine Non-typhi groups of Salmonella Culture: blood,stool or urine Yersinia enterocolitica Stool or blood cultures colonscopy Vibrio cholarae Dark fieldmicroscopy Grows as fiat yellow colonies on selective media: thiosulfate-citrate-bile-saltssucrose agar Campylobacterjejuni Microscopic exam of stool Selectivemedia with antibiotics at 42 Shigella Dysenteriae Stool culture • • • • • • Gc
Viruses that Cause gastroenteritis signs and Organism Symptoms Pal athogenesis Clinical Features Rotavirus Watery Induces histopathologic Fever and vomiting usually precede abdominal diarrhea changes in intestinal distress and diarrhea, Death in infants in vomiting mucosal cells develaping countries follows dehydration. mild fever and electrolyte imbalance. Typical course is 3-9 days. Diagnosis by immunoassay detection of rotavirus antigen in stool Norovirus Watery Induces histopathologic Abrupt onset of abdominal pain followed by diarrhea change in intestinal nausea, vomiting and diarrhea. Low-grade vomiting mucosa such as fever may occur: malaise, myalgias, and blunting of microvilli eadache are described. Typical course is 2-3 days. Diagnosis requires RT-PCR or other assays not readily available Diagnosis Rotavirus: Enzyme immunoassay( ElAs)and PCr from stool Norovirus: rt-PCr from stool
Viruses That Cause Gastroenteritis Diagnosis: Rotavirus: Enzyme immunoassay ( EIAs) and PCR from stool Norovirus: RT- PCR from stool
The experiment used to isolate and identify bacteria from feces sample IS
The experiment used to isolate and identify bacteria from feces sample is