Bacterial Infec-on. November 9, 2018 Time pm. Yaowarin Nakornpakdee, Ph.D. (Lect.)

Transcription

1 SCBM341 General Pathology Bacterial Infec-on November 9, 2018 Time pm Yaowarin Nakornpakdee, Ph.D. (Lect.) 1

2 Objec-ves Explain the virulence factors involving in bacterial infec-on Describe the pathology of bacterial infec-on Explain the host immune responses to bacterial infec-on 2

3 3

4 Bacteria Bacteria - Prokaryote 4

5 Bacteria There are two forms of cell wall structures. v Thin wall è Gram negagve bacteria v Thick wall è Gram posigve bacteria (Retains Crystal violet stain) 5

6 Bacteria 6

7 Their survive and replica-on Obligate intracellular bacteria (Inside host cells) Extracellular bacteria (Outside host cells) Faculta-ve intracellular bacteria (Both) Oxygen requirements (Form of respira-on) Aerobic (Need O 2 ) Anaerobic (Do Not Need O 2 ) Faculta-ve aerobic (Producing ATP when O 2 is present) 7

8 Bacteria 8

9 Virulence factors of bacterial infec-on 9

10 Virulence factors of bacterial infec-on 10

11 Virulence factors of bacterial infec-on Outer membrane proteins Capsule Type Secre-on System 11

12 Virulence factors of bacterial infec-on Bacterial toxin Endotoxin (lipopolysaccharide) Exotoxins Lipopolysaccharide complex Polypep-de Tetanus, Diphtheria, Botulism 12

13 Virulence factors of bacterial infec-on - Enzymes (proteases, hyaluronidases, coagulases, fibrinolysin) - Neurotoxins (Clostridium botulinum and Clostridium tetani) 13

14 Virulence factors of bacterial infec-on Superan-gens : sgmulate large number of T cells > toxic shock syndrome Exfolia-ve toxin : epidermis split away from deeper skin 14

15 Virulence factors of Bacterial Infec-on Lipase : degrades lipids on the skin surface Hemoly-c toxin : α- toxin, pore forming protein 15

16 Virulence factors of bacterial infec-on Virulence factors help bacteria invading the host causing disease evading host defenses 16

17 Pathology of bacterial infec-on 17

18 Staphylococcal Infec-on Staphylococcus aureus + cocci that form grape- like clusters cause a myriad of skin lesions (boils, carbuncles, impe-go and scalded skin) 18

19 Pathology of Staphylococcal Infec-on 19

20 Pathology of Staphylococcal Infec-on Diseases Caused by Staphylococcus aureus Scalded Skin Syndrome Sty Toxic Shock Syndrome 20

21 Streptococcal Infec-on Faculta-ve or obligate anaerobic Gram- posi-ve cocci in pairs or chains Streptococcus pyogenes (group A) causes pharyngi-s 21

22 Pathology of Streptococcal Infec-on Resemble Staphylococci Erysipelas is erythematous cutaneous swelling like bu_erfly (caused by exotoxins from S. pyogenes) Streptococcal pharyngi-s Scarlet fever Streptococcal pharyngi-s 22

23 Pathology of Streptococcal Infec-on Flesh- Ea-ng Streptococcus pyogenes Necro-zing fascii-s with blood filled vesicles. Erysipelas is caused by Strep. pyogenes 23

24 Ac-nomycosis Bacteria: Ac-nomyces Gram Posi-ve, faculta-ve anaerobic Individual: Rod- shaped Colonies: Fungus- like branched networks of hyphae 24

25 Ac-nomycosis Sob -ssue :Ac-nomycosis 25

26 Diphtheria 26

27 Anthrax 27

28 Neisserial Infec-on Gram Nega-ve diplococci, shape of coffee bean Neisseria meningi8dis Cause of meningigs in young people Invade respiratory epithelial cells > enter the blood Neisseria gonorrhoeae Important cause of sexually transmiued disease Men > urethrigs Woman > asymtomagc > pelvic inflammatory disease > inferglity, neonatal N. gonorrhoeae infecgon causes blindness 28

29 Neisseria gonorrhoeae Neisseria gonorrhea Causes Neonatal Blindness 29

30 Pseudomonas Infec-on Pseudomonas aeruginosa OpportunisGc aerobic Gram NegaGve bacillus Deadly pathogen of pagent with severe burns Complex bacteria, very resistant to angbiogcs Hospital- acquired infecgons Corneal keraggs in wearers of contact lenses 30

31 Pseudomonas aeruginosa : Corneal kera--s 31

32 Pseudomonas Infec-on 32

33 Pseudomonas Infec-on 33

34 Chancroid Caused by Hemophilus ducreyi Sexually transmi_ed Chancroid is a tender, erythematous papule and mul-ple lesions may be present Syphilis Chancroid Herpes simplex virus 34

35 Syphilis 35

36 Pathology of Syphilis Congenital syphilis - Nasal discharge - Hepatomegaly and skeletal abnormali-es - Inters--al kera--s with blindness 36

37 Borrelia spp. Lyme Disease is Caused by a Spirochete Lyme Disease early lesion at -ck bite site. Source: Medical Microbiology,

38 Tuberculosis 38

39 Pathology of Tuberculosis 39

40 Pathology of Tuberculosis 40

41 Pathology of Leprosy Mycobacterium leprae 41

42 Anaerobic Bacterial Infec-on 42

43 Pathology of Bacterial Infec-on 43

44 Clostridial Infec-ons 44

45 Host immune responses to bacterial infec-on 45

46 Cellular responses to extracellular bacteria 46

47 Cellular responses to intracellular bacteria 47

48 References Robbins and Cotran. Pathologic Basis of Disease. 9 th edigon Saunders Elsevier Jawetz, Melnick & Adelberg s. Medical Microbiology. 26 th EdiGon. LANGE Murphy K M. Janeway's immunobiology[m]. Garland Science, Abbas A K, Lichtman A H H, Pillai S. Cellular and Molecular Immunology: Elsevier Health Sciences,

49 Lab 49

50 Gall bladder : Gangrenous necrosis, Cholecys--s Code : P023, P024, P115, P272, G0041, SCPA281

51 Tes-s : Acute orchi-s Code : P063, P176(1/2), P176(2/2), P443 51

52 Kidney : Xanthogranulomatous pyelonephri-s, Hydronephrosis Code : P012, P126, P132, P296, P347, P348, P445, P447, G0039, G0040, G0085, G

53 P002 Kidney: Chronic pyelonephri-s 53

54 Small intes-ne : Tuberculosis Code : P060, P093 54

55 P060 Small intes-ne : Tuberculosis 55

56 Colon : Tuberculosis Code : P060, P093 56

57 Lymph node : Tuberculosis Code : P172(1/2), P172(2/2) 57

58 P050/P172 Lymph node: Tuberculosis (Caseous necrosis) 58

59 P045 Sob -ssue : Ac-nomycosis