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1

Host defenses against encapsulated bacteria

-Skin and Mucus membranes
-White Blood Cells (Neutrophils and Lymphocytes)
-Immunoglobulins
-Complement
-Cytokines and other acute phase reactants
-The Spleen

2

How does the polysaccharide capsule protect the bacteria

inhibits phagocytosis of the organism

3

how do pili protect the bacteria

Promotes attachment of the organism to mucosal surface

4

Where is the polysaccharide capsule?

around all the outer cellular material

5

Pathogensis: bacteria goes into the epithelium, then it can cross the blood-brain barrier, and can cause local infections like p. meningitis

Streptococcus pneumoniae

6

What part of the immune system is designed to recognize polysaccharide capsule antigens?

Marginal zone B cells
- children don't have good B cell immunity until 2+y/o

7

does the innate immune system protect against encapsulated organisms

yes, we make antibodies during colonization or infection- basis for vaccines

8

What are the encapsulated organisms

-Neisseria meningitidis
-Neisseria gonorrhea
-Streptococcus pneumoniae
-Haemophilus influenzae

9

What type of bacteria is Neisseria meningitidis

aerobic gram negative diplocccus**
encapsulated

10

Diseases caused by Neisseria meningitidis

-Meningococcemia (bacteremia) *more dangerous
-Meningococcal meningitis

11

Virulence factors of N. meningiditis

potent endotoxin

12

Neisseria meningitidis reservoir

young adults

13

Sx of Neisseria meningitidis

purpura and petechiae rash that is non-blanching
-rash may become subcutaneous bleeding and necrotic

14

when do we give the meningococcal vaccine

age 11-12, booser at 16 routinely or
>2 months if increased risk of disease (adolescents, immune disorder*, occupational exposure, travel exposure

15

pathogensis: -Exposure to colonized adult
-Acquisition of organism in nasopharynx
-Asymptomatic carriage, then immunity and colonization for 2-4 months OR Colonization which can result in Bacteremia and/or Meningitis

Neisseria meningitidis

16

HibMenCY, MCV4-D, MCV4-CRM, MPSV4, MenB-4C and MenB-FHbp are vaccines to protect against

Meningococcal
**choice of vaccine depends on age

17

Gram negative kidney bean shaped diplococci

Neisseria gonorrhea

18

Not encapsulated but has lipopolysaccharide

Neisseria gonorrhea

19

What can Neisseria gonorrhea be grown on

Chocolate agar/ carbon dioxide

20

Neisseria gonorrhea: oxidase +/-? and Catalse +/-?

+, +

21

When is it important speciate Neisseria gonorrhea

when found in children because it could indicate sexual abuse
**isolate using 2 methods in children

22

What does Neisseria gonorrhea ferment?

glucose

23

How can you identify/speciating Neisseria gonorrhea in the lab?

-sugar fermentation
-enzymatic
-fluorescent antibody
-Nucleic amplication (NAAT)***

24

Virulence characteristics of Neisseria gonorrhea

-pili
-outer membrane proteins
-ability to use iron
-IgA protease
-LPS
-cell wall peptidoglycan

25

When did the incidence of Neisseria gonorrhea increase drastically and where is it most prevalent and in who is it most prevalent in

1970s
-in the south as it is related to income
-20-30s,
-Blacks

26

Diseases caused by Neisseria gonorrhea

-vaginitis
-urethritis
-pharyngitis
-PID and salpingitis
-rectal infection
-ophthalmia neonatorum
-disseminated disease (joint inflammation)

27

many strains of N. gonorrhea are resistent to what

penicillin

28

What is N. gonorrhea treated with

Celfixime
but refer to CDC for guidelines of most recent treatment

29

How to protect against N. Gonorrhea

no vaccine

30

Bile sensitive, alpha hemolytic streptococci

Streptococcus pneumonaie