Micro facts from non Micro chapters/ hard to remember

Question 1

Strep Pyogenes - virulence factors

Answer 1

1. Streptococcal chemokine protease - degrades IL-8 from neutrophils
2. C5a peptidase - (-) C5a anaphylatoxin and (-) neutrophil chemotaxis
3. M protein - binds serum factor H, destroying C3 convertase and (-) C3 opsonization

Question 2

S. aureus Protein A function

Answer 2

binds Fc portion of IgG - to avoid opsonization

Question 3

Pseudomonas stops complement how?

Answer 3

(-) C3a, C5a

Question 4

How is pilli a virulence factor of Neisseria gon?

Answer 4

pilli are anti-phagocytic in this case ( as well as used for adherence)

Question 5

List organisms that evade immune system by antigenic variation and how?

Answer 5

Question 6

Diff in antigenic drift vs shift

Answer 6

Many viruses will mutate –> antigenic drift –> epidemics

ressortment of segmented virus genome –> antigenic shift –> pandemics

Question 7

Mycobacterium TB - how do they survive IC?

Answer 7

sulfatides inhibit phagosome-lysosome fusion,

Sulfatides - cause prod H2SO4 when they hydrolyze, live w/in cell in their own soup of sulfuric acid, (-) lysosomal fusion

Question 8

Listeria - how do they survive IC?

Answer 8

escape from phagosome into cytoplasm before lysosomal fusion

Question 9

Obligate IC microbes?

Answer 9

Viruses, Chlamydia, Rickettsia, Coxiella

Question 10

Syncytial viruses - how do they survive IC? ex/

Answer 10

paramyxo, herpes virus, HIV

Avoid humoral immunity by moving cell to cell using fusion of cell mem (move from infected cell and fuse to non infected cell - avoid time spent EC)

Question 11

Herpes virus, adeno virus, rubeola - how do they survive IC?

Answer 11

dec expression of MHC on infected cells, (-) Tc

Question 12

Key IgA protease producers

Answer 12

enter via mucosal surfaces

H. influ

S. pneumo

N. gon/menin

Question 13

Which microbes have type III secretion systems? what is it?

Answer 13

A toxin injection device - family Enterobacteriaceae, Pseudomonas, Chlamydia

Question 14

Which bact has Invasins, fxn?

Answer 14

Ex/ yersinia pseudotuberculosis

Invasins - surface prot that promote binding and penetration of non-phagocytic cells.

Question 15

Fxn of siderophores?

Answer 15

many bact produce these to allow them to chelate iron for energy

Question 16

Collagenase - ex/ of bact, use

Answer 16

Breaks peptide bonds in collagen - Clostridium perfringens

Question 17

Hyaluronidase - ex of bact, fxn?

Answer 17

Breaks down hyaluronic acid - S. pyogenes, C perfringens

Question 18

Lecithinase - bact? fxn?

Answer 18

disrupts cell mem lecithin, leading to myconecrosis

ex. Clostridium perfringens

Question 19

Streptokinase - bact? fxn?

Answer 19

dissolves fibrin clot - S. pyogenes

Question 20

Streptodornase - bact? fxn?

Answer 20

breaks down DNA rel by dead cells and dec viscosity of pus - allowing for much more rapid spread thru tissues

• Streptococcus

Question 21

bact particles that (+) neutrophils

Answer 21

Question 22

What is active component of LPS (endotoxin)? why can it not be converted into a toxoid?

Answer 22

Lipid A.

Endotoxins are heat stabile, can’t be conv to toxoid

Question 23

Endotoxins are from which bact

Answer 23

G-

Question 24

MoA of Endotoxin?

Answer 24

Bind to CD14 on mac and dendritic cells –> (+) overproduction of cytokines

Question 25

In the case of Post strep GN - what type of HS? antibodies vs what?

Answer 25

HS-III Immune complexes of Ab vs S. pyogenes serotypes M12 and M14, circulate w/ antigen and block small diam blood vessels

Question 26

HS-IV - why do IC organisms cause this? ex/

Answer 26

IC organisms (-) cell mediated immunity ex. TB, leprosy, Chlamydia PID

Question 27

What is released on death of G+ bact? fxn?

Answer 27

peptidoglycan teichoic acid fragments, chemotactic for neutrophils

Question 28

Why does Neisseria menin lead to such a rapid onset of endotoxin shock? sx?

Answer 28

Neisseria has an overproduction of outer membrane fragments --\>petechial hemorrhage and ecchymoses of palate and skin from time of onset of malaise and fever.

Question 29

Answer 29

Question 30

Anaerobes grown in what media?

Answer 30

Thioglycolate

Question 31

Early complement def

Answer 31

Increased risk of severe, recurrent pyogenic sinus and respiratory tract infections. Increased risk of SLE

Question 32

Cornyebacterium grown in

Answer 32

Tellurite agar - dark grey/black colonies Loeffler's

Question 33

Terminal compliment deficience lead to inc susceptibility to ?

Answer 33

Neisseria

Question 34

\_\_\_\_\_\_\_\_ of P aeruginosa generates ROS to kill competing pathogens.

Answer 34

Pyocyanin

Question 35

Interferons used to treat which microbial infection

Answer 35

HBV, HCV, condyloma acuminatum (HPV 6 11)

Question 36

Use of this drug is Associated with invasive CMV infection.

Answer 36

Mycophenolate (-) IMD DH

Question 37

ASO titer or anti-DNase B antibodies indicate recent ________ infection.

Answer 37

S. pyogenes

Question 38

CXR may showwidened mediastinum. - what pathogen?

Answer 38

Pulmonary anthrax can cause mediastinitis

Question 39

Fidaxomicin is a drug used to treat

Answer 39

C. diff (along with metro, vanco)

Question 40

Treatment of Nocardia vs Actinomyces

Answer 40

SNAP: Sulfonamides—Nocardia; Actinomyces—Penicillin

Question 41

What causes 1. cervical lymphadenitis in children 2. hand infection in aquarium handlers

Answer 41

1. M scrofulaceum 2. M marinum

Question 42

``` Mycobacterium Sulfatides (surface glycolipids) inhibit \_\_\_\_\_\_\_\_\_\_\_ \_\_\_\_\_\_. ```

Answer 42

Sulfatides (surface glycolipids) inhibit phagolysosomal fusion.

Question 43

Reservoir of M. leprae in US

Answer 43

armadillos

Question 44

Clofazamine is used to treat what type of Mycobacterium?

Answer 44

Lepromatous form of M. leprae

Question 45

Which Neisseria is associated with Fitz Hughes Curtis and which with Waterhouse Freidrichsen?

Answer 45

N gonn - Fitz Hughes Curtis - Perihepatitis -infection and inflammation of liver capsule and “violin string” adhesions of peritoneum to liver N. menin - Waterhouse-Friderichsen syndrome (adrenal insufficiency, fever, DIC, shock)

Question 46

rose spots on abdomen

Answer 46

Salmonella typhi - typhoid fever

Question 47

C. jejuni predisposes one to ?

Answer 47

Guillain-Barré syndrome and reactive arthritis.

Question 48

H. pylori predisposes one to what diseases?

Answer 48

peptic ulcer disease, gastric adenocarcinoma, and MALT lymphoma.

Question 49

calf myalgia, photophobia, and red eyes (no exudate)

Answer 49

Leptospira- hawaiian surfers

Question 50

Why do Beta lactams not work on Chlamydia?

Answer 50

The chlamydial cell wall lacks classic peptidoglycan (due to reduced muramic acid), rendering β-lactam antibiotics ineffective.

Question 51

How to diff between Anaplasma and Ehrlichiosis?

Answer 51

Ehrlichia, Monocytes with morulae (mulberry-like inclusions) in cytoplasm. Anaplasmosis - Granulocytes with morulae in cytoplasm.

Question 52

Causes of cold agglutinins

Answer 52

Cold agglutinin disease - autoimmune hemolytic anemia caused by Mycoplasma pneumoniae, infectious mononucleosis, CLL

Question 53

Candida leads to endocarditis in this patient pop?

Answer 53

IV drug users

Question 54

Aflatoxins produce by aspergillus leads to inc risk of what cancer?

Answer 54

HCC

Question 55

soap bubble lesions in the brain

Answer 55

Cryptococcus encephalitis

Question 56

Disc-shaped yeast seen on methenamine silver stain of lung tissue or with fluorescent antibody.

Answer 56

Pneumocystis

Question 57

flask shaped ulcers in colon

Answer 57

Entamoeba histolytica

Question 58

2 diseases that lead to ⊝ heterophile antibody test MONO - ?

Answer 58

CMV and Toxoplasma in immunocompetent host

Question 59

Unilateral periorbital swelling vs bilat

Answer 59

T. cruzi bilat - Trichinella

Question 60

spiking fevers, hepatosplenomegaly, pancytopenia

Answer 60

Visceral leishmaniasis | (kala-azar)

Question 61

Assoc with cholangiocarcinoma

Answer 61

Clonorchis sinensis

Question 62

Herpes virus acquire envelopes from ?

Answer 62

Herpesviruses acquire envelopes from nuclear membrane. - all other viruses from plasma membrane

Question 63

high fevers for several days that can cause seizures, followed by diffuse macular rash (starts on trunk then spreads to extremities)

Answer 63

HHV 6 and 7 - Roseola infantum fever first, rash later

Question 64

Councilman bodies (eosinophilic apoptotic globules) on liver biopsy.

Answer 64

Hepatitis A (Picorna), Yellow fever (flavivirus)

Question 65

Leads to villous atrophy --\> dec Na absorption and loss of K+

Answer 65

Rota virus (Reo - ds DNA linear, 10-12 segments)

Question 66

cytoplasmic inclusions of Rabies virus (negri bodies) found where?

Answer 66

found in Purkinje cells of cerebellum and in hippocampal neurons.

Question 67

Which Hepatitis is associated with aplastic anemia vs autoimmune hemolytic anemia

Answer 67

HepB aplastic Hep C AIHA

Question 68

What glomerulonephritis is assoc with Hepatitis

Answer 68

HBV - Membranous HCV - Membranoproliferative

Question 69

What vasculitis is assoc w. Hep B vs C

Answer 69

Hep B - PAN HCV - leukocytoclastic vasculitis

Question 70

Derm sx of HCV?

Answer 70

PCT, lichen planus

Question 71

Organisms typically not covered by 1st–4th generation cephalosporins

Answer 71

are LAME: Listeria, Atypicals (Chlamydia, Mycoplasma), MRSA, and Enterococci.

Question 72

Supplement K+ and Mg2+ because of altered renal tubule permeability. - Fungal Rx

Answer 72

Amphotericin B