Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Microbiology > Streptococcal > Flashcards

Streptococcal Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

Catalase (-) GM (+) bacteria

A

Streptococcus and Enterococcus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Streptococcus characteristics

A

Gram (+) cocci. Facultative and capnophilic. Fastidious species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Hemolysis of Strep

A

Beta: complete. Alpha: partial. Gamma: none.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Color of hemolysis strep

A

Beta: yellow. Alpha:green. Gamma: white.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Group A Strep (GAS)

A

Only Strep. Pyogenes. Associated with pyogenic infections. Catalase (-). Pronounced beta hemolysis. Requires enriched medium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Epidemiology of S. pyogenes

A

Respiratory droplets. Crowding populations. Deaths usually due to post-infection complications.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Seasonal diseases of S. pyogenes

A

Pharyngitis in winter. Pyoderma in summer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Virulence factors in S. pyogenes

A

Capsule. LTA. M protein. M-like protein. F-protein.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Lipoteichoic Acid

A

Binds to epithelial cells. Accounts for 60% of adhesin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

M protein

A

Adhesin. Antiphagocytic. Degrades C3b. Anchored in cell wall/extends to surface with variable sequenece at the distal end. Plasma fibrinogens binds to M-proteins, thus preventing complement activation/opsonization.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

M-like protein

A

Binds IgG and IgM. Antiphagocytic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

F protein

A

Mediates adherence to epithelial cells and internalization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Viral vs bacterial pharyngitis

A

Viral = 3Cs. Bacterial leads to abcess.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Non-suppurrative complications

A

Rheumatic fever: encapsulated and rich in M proteins.. Acture glomerulonephritis. Typically 1-3 weeks after acute pharyngitis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Scarlet fever

A

GAS produces erythogenic toxins from lysogenic phi. Diffuse erythematous rash. Strawberry tongue. Rash will disappear in 5-7 days. Signals infaction by harmful GAS.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

3 toxin types of S. pyrogenic

A

Exotoxins A, B, C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

S. impetigo/pyoderma

A

more common in the summer. Skin colonization preceds clinical infection. Usually in face and legs (minor traumas get infected). S. aureus is main cause, strep pyogenes is second major cause.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Cellulitis

A

Infection involving skin and subQ.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Erysipelas

A

Form of cellulitis, aka butterfly rash.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Necrotizing Fascilitis

A

GAS responsible for 60%. Aka hemolytic strep gangrene. Involves deep fascia.

21
Q

TSS and strep

A

Likely in pts w/ bacteremic GAS. (Always in NF pts). S. pyrogenic exotoxins act as super antigens. Resembles Staph TSS

22
Q

Paricarditis causes in ARF/RHD

A

M proteins cause IgG to cross react with heart proteins. Antibiotic prophylaxis is needed.

23
Q

Identification of S. Pyogenes

A

Beta hemolytic, catalase negative, bacitracin A disc sensitive

24
Q

Only strep that gives a positive PYR test

A

S. Pyogenes

25
Q

Strep. Agalactiae

A

Group B strep. Typical in woman urogenital track. Is a risk factor for postpartum sepsis. Babies can aquire it easily

26
Q

Virulence factors of S. Agalactiae

A

9 capsular polysaccharide types.

27
Q

Diseases of S. Agalactiae

A

Usually older/immunocompromised pts. UTI during/immediately after pregnancy. Puerperal sepsis**

28
Q

Puerperal sepsis

A

Serious septicemia during or shortly after childbirth. More rare in developed countries

29
Q

Identification of S. Agalactiae

A 
CAMP test (98-100% positive)
Bacitracin susceptibility (92% resistant)
30
Q

CAMP test

A

Positive test is hemolysis where the 2 strains intersect (S. Agalactiae and S. Aureus)

31
Q

Viridans Strep

A

Most produce a green pigment on blood agar. Prevalent in the oral cavity and URT.

32
Q

Important Viridans Strep

A 
Strep:
Mitis
Mutans
Salivarius
Sanguis
33
Q

Disease states of viridans strep

A

Sub-acute endocarditis, meningitis, pneumonia. (Dental procedures with preexisting cardiac lesions)

34
Q

Major cause of pneumonia in 1880s

A

S. Pneumoniae

35
Q

Characteristics of S. Pneumoniae

A 
Gram positive coccus
Diplococci
Fastidious (need blood/serum)
Growth enhanced bby CO2
Causes alpha hemolysis on blood agar
36
Q

Leading cause of bacterial sinusitis/middle ear infections

A

S. Pneumoniae

37
Q

Virulence of S. Pneumoniae

A

Can colonized UR with surface adhesins. Produces sIgA protease and pneumolysin (Ply) that kills the ciliated epithelial cells/phagocytes. Lysis causes edema, hemorrhage, bacterial growth.

38
Q

Capsule of S. Pneumoniae

A

Essential for virulence factor. Inhibits phagocytosis and complement pathways

39
Q

Diseases associated with S. Pneumoniae

A

Co-inflection with influenza. Pneumonia, Meningitis, Otitis media, sub-acute endocarditis

40
Q

Bacterial Pneumonia

A

Typically preceded by viral infection. High fever, productive cough, PMNs/lancet shaped diplococci, “rusty” sputum from blood leaks in capillaries. Usually lobar presentation (round in kids).

41
Q

Otitis Media

A

Infection of middle ear/sinusitis. Leading cause of OM is S. Pneumoniae! Pain and fever very common.

42
Q

3 most common causes of otitis media

A

S. Pneumoniae
Moraxella Catarrhalis
Haemophilus Influenzae

43
Q

Bacterial Meningitis and S. Pneumoniae

A

CSF: purulent, high protein, low glucose.
Severe neurological defects in survivors
Most severe bacterial meningitis

44
Q

Identification of S. Pneumonia

A

Catalase negative, bile soluble, optochin sensitive, susceptible to optochin (P disc). Can be tested for in urine. ELISA is 100% in CSF.

45
Q

Enterococcus Characteristics

A

Gram positive, usually pairs or short chains. Resistant to bile**. High salt, highly antibiotic resistant (Vanco-VRE).

46
Q

Epidemiology of Enterococcus

A

Nosocomial is very common. Typical in GI and gut.

47
Q

Most common Enterococcus diseases

A

UTI* mainly nosocomial
Peritonitis (after surgery/abdominal trauma)
Endocarditis (persistent bacteremia)

48
Q

Identification of Enterococcus

A

High salt/bile/temp
Do not lyse RBCs
Positive Pyr test

49
Q

Anaerobic cocci

A

Part of normal flora of oral, GI tract, Genitourinary tract, skin. Susceptible to common antibiotics. Easily treated if identified as anaerobic cocci.

Microbiology (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions