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Flashcards in Lecture 7 Deck (48):
1

Diseases of Gram negative Neisseria

Neisseria Meningitides and Neisseria Gonorrhea

2

What type of agar does Neisseria need?

chocolate agar (heated blood agar)

3

What is the shape of Neisseria Meningitides?

kidney shape arranged in pairs with wide polysaccharide capsule, strict aerobe

4

Does Neisseria Meningitides contain plasmids?

no plasmids since no exotoxin production

5

How is meningitides transmitted?

airborn droplets- colonize mucous membrane of nasopharynx and URT

6

Where is meningitides common?

crowded places, military camps and student camps

7

virulence factors of meningitides

1. polysaccharide capsule which resists phagocytosis, endotoxin present in cell wall responsible for septic shock and septicemia, and organism produces IgA protease, which helps to attach to mucous membrane

8

What does meningitides cause and describe it

meningitis- fever, headache, nuchal rigidity, disorientation, turbid CSF, leukocytes, organisms inside neutrophils

9

What causes septic shock and describe it

bacteremia- fever, shock, widespread purpura and disseminated intravascular clotting

10

What is the physically demonstrable symptoms of meningitis

Brudzinski's sign- severe neck stiffness causes a patients hips and knees flex when neck is flexed

11

define Kernig's sign

Severe stiffness of the hamstrings causes inability to straighten the leg when the hip is flexed to 90 degrees

12

Where do you do a lumbar puncture?

3rd or 4th lumbar spine

13

What does hemorrhage in adrenal cortex lead to?

adrenal insufficiency known as waterhouse=friedrichen syndrome

14

2 organisms causing meningitis in children

Pneumo and meningo cocci

15

Treatment for meningitis

penicillin G, sulphonamides are also effective

16

Prevention for meningitis

chemoprophylaxis- rifampicin & ciprofloxin , vaccine available- meningo coccal vaccine contains capsular polysaccharides

17

Who is Nis gonorrhoeae symptomatic in?

men and asymptomatic in women

18

Where is Ni Gonorrhoeae found?

in genital tract- less commonly in anaorectal region and oropharynx

19

Examples of virulence factors

pili, cell wall lip oligosachride and IgA protease

20

where does genetic variation occur

in pili and outer membrane proteins as a result of chromosomal rearrangement

21

clinical manifestations of Nis. Gonorrhoeae in men

causes urethritis, painful urination and pus in urine-- gonorrhea- disseminated infection lead to septic arthritis in sexually active men

22

repeated infections of the urethra can lead to what?

urethral stricture-- occluding of the urethra

23

define reiters syndrome

non gonococcal urethritis, arthritis and conjunctivitis which is immunological

24

clinical manifestations of Nis. Gonorrhea in women

mostly asymptomatic- in few it can cause purulent vaginal discharge and inner menstrual bleeding- lead to PID, ectopic pregnancy, salphingitis

25

Can fetuses contract nis. gonorrhoeae?

yes- when passing through the birth canal- severe purulent bilateral conjunctivitis can occur- other STDs can co-exist

26

Treatment for Nis. Gonorrhoeae

Penicillin G is drug of choice- nowadays ceftrioxone is given

27

Prevention of Nis. Gonorrhoeae

use of a condom- there is no vaccine- babies can be given erythromycin drops for eyes

28

List the 4 organisms in the Gram + Category

Bacillus, Clostridium, Corney bacterium diphtheriae and lysteriae momcytogens

29

Which gram + groups are spore forming?

Bacillus and Clostridium

30

Which gram + groups are non-spore forming?

Corney bacterium diptheriae and lysteriae

31

What are the two species of Bacillus and is it aerobic or anaerobic?

aerobic- species are B anthrax and B cereus

32

What are the four species of Clostridium and is it aerobic or anaerobic?

anaerobic- Cl tetani, Cl botulinum, Cl perfingens, Cl difficile

33

Describe B Anthrax

large rods with square ends with spores in the center- arranged in chains (Bamboo stick appearance) - non motile

34

What is the capsule of B anthrax?

Capsule is D glutamate- antigenic and antiphagocytic

35

Anthrax is mainly a disease of_____

herbivorous animals (cattle, goat, horse) - humans get the disease accidentally

36

three forms humans can get B Anthrax

skin, lungs, gastro intestinal track

37

Transmission of B Anthrax

spores found in soil- remain for years- can get from wound infection. Inhale, ingest of contaminated meat, inhalation

38

What is wool sorter's disease?

inhalation of B Anthrax from hides, skin, wool and bristles

39

What is malignant pustule and how do you get it?

Painless ulcer with black crust on the skinw ith surrounding edema- caused by skin exposure to B Anthrax

40

Define pulmonary anthrax of B Anthrax

initially flu like symptoms, dry cough, retro sternal pressure, septic shock and death

41

How do you diagnose Pulmonary Anthrax disease?

Xray shows widening of the mediastinum and pleural effusion

42

Results of GI track B Anthrax

vomiting, abdominal pain, bloody diarrhea

43

What does the lab diagnosis of B Anthrax look like?

2-3 grayish colonies: medusa head appearance on blood agar, in gelatin medium you will see inverted fir tree appearance, and smears show characteristic chains (bamboo sticks-blue)

44

What is used to treat B Anthrax?

Penicillin G is treatment of choice

45

What can be used to prevent B Anthrax?

Ciprofloxacin, Doxycycline- animals dyin of anthrax disease should be burnt not buried , vaccine is available

46

Describe B Cereus

a soil dwelling organism which causes food poisoning- spores found on food grains survive steaming and frying

47

2 types of enterotoxins produced by B Cereus

1. Causes ADP ribosylation of G protein resulting in non-bloody diarrhea like cholera 2. acts as super Ag causes vomiting and nausea

48

Treatment for B Cereus

treatment only symptomatic- self limiting (no treatment needed)