Flashcards in Bacteria 2 Deck (80):
1
2 examples of common upper respiratory infections caused by normal flora?
1) Ottis media
2) sinusitis
2
What causes upper respiratory infections via normal flora?
Blockage of sinus ostia, estachian tube by virally induced or allergic inflammation
3
What causes invasive Upper respiratory disease in neonates?
E. coli and Group B Strep
4
What causes IURD in children 1-5?
H. influenzae type B
5
What cause IURD in adolscents and young adults?
N. meningitidis
6
What causes IURD in all age groups?
Strep pneumoniae
7
What is the key to pathogenicity for bacteria?
Encapsulation
8
Where does the pathogenesis begin?
Upper respiratory infection
9
What happens after the initial Upper respiratory infection?
Invasion of bacteria into deep tissues and bloodstream
10
What happens when the bacteria is disseminated in the body?
Bacteremia
11
What leads to vascular leakage?
Endothelial and macrophage activation by LPS
12
Vascular leakage leads to what?
Disseminated intravascular coagulation (DIC)
13
Infections with encapsulated organisms require what that Staph and strep infections don't?
Antibodies or complement
14
What is a splenic condition that increases susceptibility to encapsulated organisms?
Asplenia
15
Where is Pneumococcus found?
Normal Upper respiratory flora
16
What does Pneumococcus look like?
Gram + diplococcus
17
Pneumococcus virulence factors?
Capsule and PspC (Pneumococcal surface protein C)
18
Disease caused by Pneumococcus?
Sepsis and meningitis
19
Where is N. meningitidis?
Exogenous
20
What does N. meningitides look like?
Gram -, diplococcus
21
Virulence factors of N. meningitides?
Capsule and LPS
22
Disease caused by N. meningitides?
DIC, sepsis, meningitis
23
Where is N. gonorrhea found?
Exogenous
24
What does N. gonorrhea look like?
Gram - diplococcus
25
Virulence factors of N. gonorrhea?
Capsule and LOS
26
Diseases of N. gonorrhea?
Septic arthritis
27
Where is H. influenza found?
Normal flora, type B exogenous
28
What does H. influenza look like?
Gram - pleomorphic
29
Virulence factors of H. influenza?
Capsule and LPS
30
Disease caused by H. Influenzae?
Sepsis and meningitis
31
What does invasive disease lead to?
Bacteremia
32
What is found on bacterial capsule that causes Sepsis or DIC?
LPS or PspC
33
Why do encapsulted bacteria and meningitis go to CSF?
No complement for opsonization
34
In sepsis what does LPS stimulate?
Toll Like Receptors to induce systemic cytokine secretion and endothelial cell activation
35
What is DIC?
Systemic coagulation caused by bacteria
36
What limits Gonococci's ability to cause DIC?
They have LOS instead of LPS
37
Most common caused of community acquired pneumonia ?
Strep pneumoniae
38
What special attachment does Strep pneumoniae have on its polysaccharide capsule?
PspC
39
What virulence factor of Strep Pneumoniae inhibits alternate complement pathway?
PspA
40
Who is the pneumococcal conjugate vaccine for?
Children younger than 5 and adults with risk factors
41
Who is the pneumococcal polysaccharide vaccine for?
Children two years or older
42
What is one of the main nutritional requirements for Neisseria?
Iron
43
Where is Neiserria found?
Not normal flora, exogenous
44
Incubation time N. meningitides?
Less than a week
45
What is N. meningitidis susceptible to?
Penicillin
46
What causes the petechial rash in N. meningitidis?
Microhemorrhages in capillaries
47
What is Waterhouse Friderichsen syndrome?
Hemorrhage into adrenals
48
Are vaccinations effective for meningococcal disease?
Yes, doesn't cover group B though which is biggest in neonates
49
Why do N. meningitidis vaccines not work in neonates?
Neonates cannot respond to capsular antigen vaccine
50
How does N. Gonorrhea differ from N. Meningitidis?
Different capsule allows different behavior
51
Where does N. Gonorrhea attach?
Columnar and transitional epithelia mucous membranes of genital tract, rectum, and nasopharynx
52
N. Gonorrhea IgA protease allows for what?
Evasion of mucosal immunity
53
Why has it been difficult to make a vaccine for N. Gonorrhea?
Antigenic variability
54
What is a defining characteristic of H. influenza?
Unencapsulated mostly
55
What can make H. influenza dangerous?
Encapsulation and endotoxin
56
What is the window of vulnerability for invasive disease of Type B?
3 months to 3 years due to bad protective antibody response to type B capsular antigens
57
What is a good way to vaccinate toddlers and infants with Type B?
Conjugate capsule with protein
58
What causes Diphtheria?
Corynebacterium diphtheria
59
What causes the membrane formation of Diphtheria?
Local epithelial necrosis which releases exotoxin A
60
What is characteristic of Whooping Cough?
Lymphocytosis
61
What does the exotoxin of Whooping Cough do?
Leads to local ciliary paralysis
62
What does the DPT vaccine do for cases of Whooping Cough?
Gives immunization to Exotoxin
63
What is the Pertussis vaccine called?
Tdap for 10 years and older, DTaP for children younger than 7 years
64
What does Diphtheria look like?
Gram + rod
65
What does the exotoxin do in Diphtheria?
Inhibits protein synthesis and leads to fatty myocardial changes
66
Biggest reason for death with Diphtheria?
Cardiac failure
67
What type of infection are UTIs generally?
Gram negative infections
68
What are the 2 main types of gram - infections?
1)Spread of organisms that have colonized GI tract
2) Contamination of tissues and materials from hospital environment
69
Cause of most uncomplicated UTIs in absence of obstruction?
E. coli
70
What causes suppurative infections of abdominal cavity?
Secondary to obstruction, perforation, and trauma
71
What is Klebsiella pneumonia associated with?
Aspiration in hospital setting
72
Characteristic of Klebsiella and Enterobacter in septicemia?
Association with thick mucoid capsule
73
Defining characterstic of proteus marabilis?
Staghorn pyelonephritis due to chronic pyelonephritis
74
What does Serrate marcescens cause?
Pneumonia and UTIs
75
What defines Pseudomonas aeruginosa histologically?
Blue haze around blood vessels
76
What is the common pathogenic organism in cystic fibrosis?
Pseudomonas aeruginosa
77
Outbreak of Legionella associated with?
Community outbreaks associated with contaminated aerosolized water supplies
78
Biggest problem with Legionella?
Fibrinopurulent necrosis of pulmonary tissue
79
How does helicobacter pylori survive in the stomach?
Urease creates protective layer of ammonia around organism
80