Clinical ID

Question 1

Poliovirus

Poliomyelitis

Answer 1

virus

Question 2

Chlamydia trachomatis

Trachoma

Answer 2

chlamydiae

Question 3

Rickettsia prowazekii

Typhus fever

Answer 3

Rickettsiae

Question 4

Staphylococcus epidermidis

Wound Infection

Answer 4

bacteria

Question 5

Vibrio cholerae

Cholera

Answer 5

bacterai

Question 6

Streptococcus pneumoniae

Pneumonia

Answer 6

bacteria

Question 7

Mycobacterium tuberculosis

Tuberculosis

Answer 7

bacteria

Question 8

trichophyton sp.

Tinea pedis

Answer 8

fungi imperfecti

Question 9

candida albicans

Thrush

Answer 9

fungi imperfecti

Question 10

sporothrix schenckii

Sporotrichosis

Answer 10

fungi imperfecti

Question 11

Histoplasma capsulatum

Histoplasmosis

Answer 11

fungi imperfecti

Question 12

Giardia lamblia

Giardiasis

Answer 12

Protozoa

Question 13

trypanosoma gambiense

sleeping sickness

Answer 13

Protozoa

Question 14

trypanosoma cruzi

Chagas disease

Answer 14

Protozoa

Question 15

Leishmania donovani

Kala-azar

Answer 15

Protozoa

Question 16

enterobius vermicularis

Oxyuriasis

Answer 16

Helminths

Question 17

Wuchereria bancrofti

Filariasis

Answer 17

Helminths

Question 18

Trichinella Spiralis

Trichinosis

Answer 18

Helminths

Question 19

What are the human host barriers to infection?

Answer 19

1. intact host skin and mucosal surfaces
2. secretory-excretory products
   ex. lysozyme in tears and stomach acids

Question 20

What are the mechanisms of bacteria induced injury

Answer 20

1. bacterial virulence
   - depends on ability of bacteria to adhere, invade, and deliver toxic moieties
2. bacterial adherence
   a. adhesins are bacterial surface molecules that bind to host cells
   b. entry into macrophages
   c. entry into epithelial cells
3. bacterial endotoxin
   - LPS -induce host cytokines release to cause fever, activate macrophages and b-cells
4. bacterial exotoxins
   - toxins released by bacteria that interfere with metabolism and allow bacteria to outgrow competing bacteria

Question 21

What are the microbial pathogens that exhibit significant antigenic variation?

Answer 21

1. rhinoviruses
2. influenza virus
3. neisseria gonorrhoeae
4. borrelia hermsii-relapsing fever
5. borrelia burgdorferi-lyme disease
6. trypanosoma brucei-African sleeping sickness
7. giardia lamblia
8. plasmodium falciparum-severe malaria

Question 22

What are the 5 types of inflammatory response? give an example of a microorganism that would cause this type of inflammation

Answer 22

1. suppurative (polymorphonuclear) inflammation
   - bacteria recruit neutrophils, increased vascular permeability directly by chemoattractive peptides and indirectly by release of endotoxin which stimulates macrophages to release cytokines and chemoattractant
   - caused by pyogenic bacteria
2. mononuclear and granulomatous inflammation
   - diffuse, predominantly mononuclear interstitial infiltrates form in response to pathogens
   - syphilis chancres-lymphocytes
   - mycobacterial granulomas-macrophages
   - tb and syphilis
3. cytopathic-cytoproliferative inflammation
   - reactions characteristic of virus-mediated damage to indicudual host cells in the absence of host inflammatory response
   - results in: inclusion bodies (CMV), polykaryons following cell fusion (measles), blisters due to cell damage (herpes virus), morphologic lesions (venereal warts/HPV), dysplastic changes and cancer
4. necrotizing inflammation
   - rapid and severe tissue damage with predominant cell death in the absence of inflammatory infiltrates
   - caused by uncontrolled viral infections, secreted bacterial toxins or cytolysis of host cells in protozoa infections (eg. necrotizing fasciitis caused by group A streptococcus)
5. chronic inflammation and scarring
   - chronic inflammation can lead to either complete healing or to extensive scarring
   - several inert organism cause damage by the scarring response (ex. schistosome eggs-parasite)

Question 23

What are the three classes of Helminthes? Give an example of each

Answer 23

1. roundworms
   - hookworms and trichinella
2. flatworms
   - tapeworms
3. flukes
   - schistosomes