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- 1. Bacteriology-2 الثالثة المحاضـــرة المقرر مدرس / د . الحبيشـــيعمــرو Enterobacteriaceae E. coli
- 2. I) Basic informationof Enterobacteriaceae Large group All members are gram negative bacilli A
- 3. ❖ Normal florain intestine & animals ❖ Some in the environmental I) Basic information of Enterobacteriaceae B
- 4. Inhibition of pathogenic colonization I)Basic information of Enterobacteriaceae Importance C
- 5. A- Opportunistic (E.coli, Klebsiella Enterobacter) I)Basic information of Enterobacteriaceae Importance UTI Change in the natural habitat C
- 6. B- Enteric pathogen ❖Salmonella ❖Shigella ❖E.coli* I)Basic information of Enterobacteriaceae Importance C
- 7. Multi-drug resistant (ESBL). I) Basic informationof Enterobacteriaceae D
- 8. II)General features ofEnterobacteriaceae ❖ Facultative anaerobes ❖ 38 ATP (Aerobic) ❖ 2 ATP (Anaerobic) 1
- 9. II)General features ofEnterobacteriaceae 2 Oxidase negative
- 10. II)General features ofEnterobacteriaceae 3 All members are ferment glucose with acid production.
- 11. II)General features ofEnterobacteriaceae 4 Reduce nitrates to nitrites to (NO2) (NO3) Red α-naphthylamine
- 12. II)General features ofEnterobacteriaceae P. aeruginosa & Bacteroides species are non-Enterobacteriaceae instead of gram negative bacilli and found in intestine. Give reason
- 13. II)General features ofEnterobacteriaceae P. aeruginosa ❖ Obligate aerobes ❖ Oxidase positive ❖ No glucose ferment Bacteroides ❖ Obligate anaerobes ❖ No reduce nitrate
- 14. III) Classification They aredivided into two groups according to their effect on lactose. 1- Non-lactose fermenter 2- Lactose fermenter Salmonella Shigella Proteus Escherichia coli Klebsiella Citrobacter Enterobacter Serratia
- 15. Biochemical reactions Triple sugariron (TSI)
- 16. Triple sugar iron •0.1% glucose • 1% lactose • 1% sucrose • Ferrous sulfate • pH indicator: Phenol red Used for identification of: • Enterobacteriaceae based on the fermentation of glucose, lactose, sucrose and the production of gas and H2S.
- 17. a) Acid overacid (A/A) Inoculation ferment glucose Acid Phenol red Yellow color Then start to lactose or sucrose Acid (A/A)
- 18.
- 19. b) Gas production Detectionof gas production by break up the medium or pushed up the tube.
- 20. c) H2S production Bacteria (Reduce) Sulfur Hydrogensulfide (H2S) iron Ferric sulfide (Black)
- 21.
- 22. I) Morphology ofE. coli ❖Gram negative bacilli ❖Some strain capsulated ❖Motile ❖Non-spore forming
- 23. II) Culture ofE. coli ❖MacConkey’s agar ❖Facultative anaerobes Lactose fermenter (Rose pink)
- 24. III) Antigenic structure 3antigens used in classification O antigen (Somatic Ag) H antigen (Flagellar Ag) K antigen (Capsular Ag) Serological
- 25. III) Antigenic structure 1 Oantigen (Lipopolysaccharide (Many different O)
- 26. III) Antigenic structure Hantigen (Flagellar) 2 (Many different H)
- 27. III) Antigenic structure Kantigen (Capsular) 3 (Many different K)
- 28. III) Antigenic structure Manydifferent O, H & K antigens >1000 antigenic types of E.coli (>1000 strains of E.coli)
- 29.
- 30. IV) Virulence factors Capsule(K Ag) Inhibit phagocytosis 2
- 31.
- 32. IV) Virulence factors Exotoxin (Enterotoxin) a)Heat labile (HL) b) Heat stable (HS) (ETEC) 4
- 33. IV) Virulence factors Verotoxin (Shigatoxin) (EHEC) 5 Destroys of microvilli
- 34. I) UTI Diseases ofEscherichia coli
- 35. I) UTI • 90%by E.coli (uropathogenic) Cystitis Pyelonephritis ➢ Dysuria ➢ Polyuria ➢ Pyuria ➢Flank pain
- 36. I) UTI Why UTIin female more than Male??
- 37. II) Neonatal meningitis During delivery Aspirationof intestinal & genital tract secretion Nasopharynx Blood Meninges E. coli (K1 Ag) causes 40% E. coli
- 38. III) Sepsis &pneumonia Wound sepsis Pneumonia (Immunocompromised)
- 39.
- 40. A) Enterotoxigenic E.coli (ETEC) Traveler’s diarrhea Infants
- 41. A) Enterotoxigenic E.coli (ETEC) Ingestion of contaminated food & water by ETEC 1
- 42. A) Enterotoxigenic E.coli (ETEC) Colonize the small intestine by pili 2
- 43. A) Enterotoxigenic E.coli (ETEC) Produce cholera like toxin (LT &ST) (Enterotoxin) 3
- 44. A) Enterotoxigenic E.coli (ETEC) Heat labile toxin (LT) 3 adenylate cyclase ATP A A A cAMP (5 B subunit +1 A subunit) Diarrhea I.P 1- 4 days
- 45. A) Enterotoxigenic E.coli (ETEC) Heat stable toxin (ST) 3 Fluid secretion GTP cGMP Guanylate cyclase
- 46. 2)Enteropathogenic E.coli (EPEC) Diarrheain Infants Poor sanitation
- 47. 2)Enteropathogenic E.coli (EPEC) Fecaloral route
- 48. 2)Enteropathogenic E.coli (EPEC) Serotypes O55,O111 &O26 (Somatic O Ag)
- 49. 2)Enteropathogenic E.coli (EPEC) EPEC Destroysmicrovilli Preventing of absorption & secretion Severe watery diarrhea By pili (bundle forming pili)
- 50. 2)Enteropathogenic E.coli (EPEC) ❖Fever ❖ Watery diarrhea (Non-bloody) ❖ Vomiting
- 51. 3) Enteroinvasive E.coli(EIEC) (Like shigllae) Ingestion Attach to the intestinal mucosa via pili. Invasion of the intestinal cells Lysis the cell & spread to neighboring cells Destruction of cells & inflammation Dysentery like diarrhea
- 52. 3) Enteroinvasive E.coli(EIEC) ❖ Fever ❖ Sever abdominal cramps ❖ Bloody diarrhea (mucus & pus) ❖ Vomiting. (Resembles shigellosis).
- 53. 3) Enteroinvasive E.coli(EIEC) ❖The EIEC are like Shigella. ❖Non motile, non lactose fermenter
- 54. 4) Enteroaggregative E.coli (EAEC) Fecal oral route
- 55. 4) Enteroaggregative E.coli (EAEC) EAEC aggregate to intestinal mucosa Producing ST like toxin (Enterotoxin) Persistent diarrhea in children &HIV patients
- 56. 5) Enterohaemorrhagic E.coli(EHEC) ❖ Verotoxin ❖ Shiga-toxin producing E.coli(STEC) O157:H7 Vero=monkey Toxic to monkey cells in tissue culture
- 57. Mode of transmissionof EHEC O157 2) Undercooked meat 1) Raw vegetables Water 3) FOR
- 58. 5) Enterohaemorrhagic E.coli(EHEC) EHEC (O157) binds to cells in the large intestine (O157)VT 2
- 59. 5) Enterohaemorrhagic E.coli(EHEC) EHEC (O157) VT destroys microvilli 3 VT
- 60. 5) Enterohaemorrhagic E.coli(EHEC) Verotoxin enters blood, causing vascular endothelial damage 4 VT VT
- 61. 5) Enterohaemorrhagic E.coli(EHEC) 5 VT VT ➢Hemorrhagic colitis ➢Hemolytic uremic syndrome. Note: (EHEC does not ferment Sorbitol)
- 62. 5) Enterohaemorrhagic E.coli(EHEC) Antibiotic should not be used HUS if antibiotics used.
- 63. Indicators of fecalpollution of water ❖ E. Coli ❖ S. Faecalis ❖ Cl. Perfringenes
- 64. Indicators of fecalpollution of water ❖ Give reason • Klebsiella spp can not used as indicator for fecal pollution of water.
- 65. Indicators of fecalpollution of water Because Klebsiella spp inhabitant in intestine & environmental (soil).
- 66. Lab. diagnosis ofE. coli
- 67. 1) Specimen ❖Urine (MSU) ❖Woundswab ❖Respiratory secretions ❖CSF ❖Diarrhea
- 68. 2) Direct detection A)Gram stain ❖Useful only in CSF
- 69. 2) Direct detection B)E. coli K1 Ag in CSF ❖Latex agglutination
- 70. 3) Cultivation ❖ MacConkeyagar ❖ Blood agar ❖ CLED agar
- 71.
- 72.
- 73.
- 74. (In case ofdiarrhea) Sorbitol MacConkey agar 95% of strains are sorbital fermenters EHEC Sorbitol non fermenter
- 75. 4) Identification ❖I MV C + + - -
- 76. 4) Identification • Theanalytical profile index (API) (Biochemical tests for identification)
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- 78.
- 79. Treatment • For UTI: •Sulfamethoxazole/trimethoprim is a first-choice medication. • For neonatal meningitis: Ampicillin plus Gentamicin.
- 80. Prevention • How toprevent E. coli infection from spreading???