Clinical Significant Strep And Strep-like Organisms Flashcards
What is the essential virulence factor of S. pyogenes?
M protein
This protein is encoded of emm gene.
M proteins
How many serotypes of M protein thus S. pyogenes have?
80 serotypes
Roles of M protein.
Evades phagocytosis
Adhesion to the mucosal cells
The most common serotype of M protein found in pharyngitis.
M1
Which of the following is/are not virulence factors of S. pyogenes
A. Fibronectin-binding protein (Protein F)
B. Neuraminidase
C. Streptolysin O
D. Streptokinase
B
What are the virulence factors of S. pyogenes?
M protein
Lipotechoic acid
Hyaluronic acid capsule
Protein F
Extracellular products
(Enzymes, hemolysin, exotoxins)
What are the extracellular products of S. pyogenes ?
Extracellular products
- Streptolysin O
- Streptolysin S
- DNase
-streptokinase
-hyaluronidase
-streptococcal pyrogenic exotoxin
(Erythrogenic toxins)
Four immunologically distinct exotoxins types found in S. pyogenes?
SpeA
SpeB
SpeC
SpeF
Which virulence factors of S. pyogenes is not for adhesion?
A. M protein
B. protein F
C. Lipotechoic acid
D. Hyaluronic acid capsule
D.
- Hyaluronic acid capsule:
- Streptolysin S:
- Streptolysin O:
A. Weakly immunogenic
B. Highly immunogenic
C. Nonimmunogenic
- A
- C
- B
Virulence factor that mask the antigen to avoid phagocytosis.
Hyaluronic acid capsule
What is the common DNase in S. pyogenes?
DNase B
It is responsible for hemolysis in the SBA plate incubated ANAEROBICALLY.
Streptolysin O
The SLO leaves antibodies in hemolysin that can be measured in what test?
Antistreptolysin O (ASO) test
It is an oxygen stable type of Streptolysin and resposibel for hemolysis incubated AEROBICALLY.
Streptolysin S
This virulence factor of S. pyogenes cause lysis of fibrin clots.
Streptokinase
T or F
Group C and G alse have streptokinase.
True
It is the spreading factor of S. pyogenes.
Hyaluronidase
Some strain of S. pyogenes cause red spreading rash called ____ and cause by what virulence factor?
- Scarlet fever
- streptococcal pyrogenic exotixins
This virulence factors of S. pyogenes is superantigen.
Steptococcal pyrogenic toxins
Clinical infections of S. pyogenes
- Bacterial pharyngitis
- pyodermal infection
- necrotizing fasciitis
-streptococcal toxic shock syndrome
Poststreptococcal sequelae
Mos common clinical manifestation of GAS infection
Bacterial pharyngitis
T or F
Strep throat is usually seen in children between 3-4 yrs. Old.
False- 5-15 yrs old
Bacterial pharyngitis could be spread through___.
Droplets or close contact
Which is not a pyodermal infection of S. pyogenes?
A. Folliculitis
B. Impetigo
C. Erysipelas
D. Cellulitis
A.
This skin infection begins in small vesicles that progress to weeping lesions. Occurs through minor abrasion and isect bites bites.
Impetigo
A rare infection of the skin and subcutaneous tissues is observed frequently in elderly patients.
Erysipelas
Can develop following deeper invasion by strep.
Cellulitis
An invasive infection characterized by rapid progressing inflammation and necrosis of the skin, Subcutaneous fat, and fascia.
Necrotizing fasciitis
What type of NF cause by polymicrobial infection?
Type 1
NF cause only by GAS.
Type 2
Type of NF that is a gas gangrene/ clostridial myonecrosis
Type 3
This infection of S. pyogenes cause the entire organ system to collapse.
Streptococcal Toxic Shock Syndrome
GAS associated with TSS produce what type of streptoccal pyrogenic exotoxins?
SpeA
Two serious complications of Postreptococcal sequelae infection.
Rheumatic Fever (RF)
Acute glomerulonephritis
Characterized by fever, an inflammation of the heart, joints, blood vessels, and subcutaneous tissues.
Rheumatic fever
Circulating immune complexes found in the serum of patients with___.
Acute glomerulonephritis