MIDTERM 01 - Gram-Positive Cocci

Question 1

Gram-positive spherical cells arranged in grapelike irregular clusters

Answer 1

Staphylococci

Question 2

Staphylococci produces __________, which converts H2O2 to H2O and O2

Answer 2

Catalase

Question 3

2 Staphylococcus aureus enzymes (CC)

Answer 3

Coagulase, Clumping factor

Question 4

Clots oxalated or citrated plasma (Staphylococcus aureus enzymes)

Answer 4

Coagulase

Question 5

Adheres organism to fibrinogen and fibrin (Staphylococcus aureus enzymes)

Answer 5

Clumping factor

Question 6

Lyse many cells and creates pores that cause release of inflammatory mediators (Staphylococcus aureus toxins)

Answer 6

Hemolysins

Question 7

Is a superantigen; produces the generalized desquamation of staphylococcal scaled skin syndrome (Staphylococcus aureus toxins)

Answer 7

Exfoliative toxins

Question 8

Is a superantigen that binds to MHC-II molecules which promotes the manifestations of toxic shock syndrome (Staphylococcus aureus toxins)

Answer 8

Toxic shock syndrome toxin-1 (TSST-1)

Question 9

Is heat stable, resistant to gut enzymes, and causes food poisoning (Staphylococcus aureus toxins)

Answer 9

Enterotoxins

Question 10

Characterized by a localized abscess (Staphylococcus aureus clinical findings)

Answer 10

Furuncle/Carbuncle

Question 11

Characterized by a local infection of superficial layers of skin, especially in children (Staphylococcus aureus clinical findings)

Answer 11

Impetigo/Pyoderma

Question 12

Characterized by a supparation (abscess) that occurs in other parts causing endocarditis, osteomyelitis, meningitis, and pneumonia (Staphylococcus aureus clinical findings)

Answer 12

Bacteremia

Question 13

Supparation in blood vessels of the metaphysis of a long bone

Answer 13

Osteomyelitis

Question 14

Its incubation period is 1-8 hours; characterized by symptoms that include N/V, diarrhea, and fever (Staphylococcus aureus clinical findings)

Answer 14

Food poisoning

Question 15

Characterized by an abrupt onset of high fever, vomiting, diarrhea, myalgia, scarlatiniform rash, and hypotension with cardiac and renal failure in most severe cases (Staphylococcus aureus clinical findings)

Answer 15

Toxic shock syndrome

Question 16

Characterized by redness and tenderness of the central face, neck, trunk, and intertriginous zones (Staphylococcus aureus clinical findings)

Answer 16

Scalded skin syndrome

Question 17

Enzyme that hydrolyzes β-lactam antibiotics; give β-lactamase resistant penicillins

Answer 17

β-lactamase

Question 18

Gene that gives resistance to β-lactamase resistant penicillins due to low affinity PBPs; give vancomycin

Answer 18

mecA gene

Question 19

Bacteria that causes 75% of coagulase-negative staphylococcal infections (Streptococcus species)

Answer 19

Streptococcus epidermidis

Question 20

Bacteria that is part of the normal flora of the skin, respiratory tract, and GIT; relatively common cause of UTIs in young women (Streptococcus species)

Answer 20

Streptococcus saprophyticus

Question 21

Gram-positive spherical cells arranged in pairs or chains

Answer 21

Streptococci

Question 22

Grouping based on Lancefield antigens (carbohydrates) present in the cell wall

Answer 22

Lancefield grouping

Question 23

N-acetylglucosamine (Lancefield group)

Answer 23

Group A

Question 24

Rhamnose-glucosamine (Lancefield group)

Answer 24

Group B

Question 25

Rhamnose-N-acetylgalactosamine (Lancefield group)

Answer 25

Group C

Question 26

Glycerol teichoic acid containing D-alanine and glucose (Lancefield group)

Answer 26

Group D

Question 27

Glucopyranosyl-N-acetylgalactosamine (Lancefield group)

Answer 27

Group F

Question 28

Also known as pneumococci; normal flora of the upper respiratory tract of 5-40% of humans (Streptococcus species)

Answer 28

Streptococcus pneumoniae

Question 29

Pneumonia of sudden onset; symptoms include fever, chills, sharp pleural pain, and bloody or rusty colored sputum (Clinical findings of Streptococcus pneumoniae)

Answer 29

Community-acquired pneumonia

Question 30

Treatment for Streptococcus pneumoniae

Answer 30

Parenteral β-lactams

Question 31

2 vaccines used for prevention of Streptococcus pneumoniae

Answer 31

PPSV23, PCV13

Question 32

The most prevalent members of the normal microbiota of the upper respiratory tract (Examples of gram-positive cocci)

Answer 32

Viridans streptococci

Question 33

Condition that is due to large polysaccharides synthesized by Streptococcus mutans (Clinical findings of Viridans streptococci)

Answer 33

Dental caries

Question 34

Condition that involves the rapid destruction of the valves; leads to fatal cardiac failure in days-weeks unless surgery is performed (Clinical findings of Viridans streptococci)

Answer 34

Acute endocarditis

Question 35

Condition that is slowly progressive and often involves abnormal valves (Clinical findings of Viridans streptococci)

Answer 35

Subacute endocarditis

Question 36

Major virulence factor of Streptococcus pyogenes

Answer 36

M protein

Question 37

Enzyme that transforms plasminogen into plasmin, which digests fibrin, allowing bacteria to escape from blood clots (Streptococcus pyogenes enzymes)

Answer 37

Streptokinase (Fibrinolysin)

Question 38

Enzyme that degrades DNA and liquefies pus, allowing the bacteria to spread (Streptococcus pyogenes enzymes)

Answer 38

Deoxyribonuclease (DNAse)

Question 39

Enzyme that hydrolyzes hyaluronic acid, a component of ground substance in ECM of CT and aids in spreading (Streptococcus pyogenes enzymes)

Answer 39

Hyaluronidase

Question 40

Is a superantigen that is associated with streptococcal toxic shock syndrome and scarlet fever (Streptococcus pyogenes toxins)

Answer 40

Pyrogenic exotoxins (Erythrogenic toxins)

Question 41

Hemolysin that induces antistreptolysin O (ASO) production (Streptococcus pyogenes toxins)

Answer 41

Streptolysin O

Question 42

Hemolysin responsible for β-hemolysis on BAP; not antigenic (Streptococcus pyogenes toxins)

Answer 42

Streptolysin S

Question 43

Its portal of entry is the skin; presents raised, red lesions, a brawny edema, and a rapidly advancing, sharply demarcated margin (Clinical findings of Streptococcus pyogenes)

Answer 43

Erysipelas

Question 44

Its portal of entry is parenteral; is an acute, rapidly spreading infection of the skin and subcutaneous tissues (Clinical findings of Streptococcus pyogenes)

Answer 44

Cellulitis

Question 45

Its portal of entry is parenteral; it is a "flesh eating disease" that is extensive and involves a very rapidly spreading necrosis of the skin, tissues, and fascia (Clinical findings of Streptococcus pyogenes)

Answer 45

Necrotizing fasciitis (Streptococcal gangrene)

Question 46

Its portal of entry is the uterus; it is a septicemia originating in the infected wound after delivery (Clinical findings of Streptococcus pyogenes)

Answer 46

Puerperal fever

Question 47

Its portal of entry is parenteral; it can be rapidly fatal (Clinical findings of Streptococcus pyogenes)

Answer 47

Bacteremia/Sepsis

Question 48

It is the most common infection caused by Streptococcus pyogenes; it involves adherence to pharyngeal epithelium via lipoteichoic acid binding to fibronectin (Clinical findings of Streptococcus pyogenes)

Answer 48

Streptococcal pharyngitis

Question 49

It leads to shock, bacteremia, respiratory failure, and multiorgan failure; tends to occur after minor trauma in otherwise healthy persons with several presentations of soft tissue infection (Clinical findings of Streptococcus pyogenes)

Answer 49

Streptococcal toxic shock syndrome

Question 50

It associated with pharyngitis or with skin or soft tissue infection; its symptoms include a strawberry tongue and bright red, sandpaper rash (Clinical findings of Streptococcus pyogenes)

Answer 50

Scarlet fever

Question 51

Are autoimmune disorders which appears after an acute S. pyogenes infection

Answer 51

Poststreptococcal diseases

Question 52

A poststreptococcal disease more commonly preceded by a Streptococcus pyogenes skin infection or pharyngitis (Poststreptococcal diseases)

Answer 52

Poststreptococcal glomerulonephritis

Question 53

A poststreptococcal disease more commonly preceded by pharyngitis (Poststreptococcal diseases)

Answer 53

Rheumatic fever

Question 54

Most serious sequela of S. pyogenes; mainly a disease of children 5-14 years old (Poststreptococcal diseases)

Answer 54

Rheumatic fever

Question 55

Treatment for Streptococcus pyogenes

Answer 55

Penicillin G

Question 56

Part of the normal vaginal flora and lower GIT in 5-30% of women (Streptococcus species)

Answer 56

Streptococcus agalactiae

Question 57

Involves an infection during the 1st month; may present as fulminant sepsis, meningitis, or respiratory distress syndrome (Clinical findings of Streptococcus agalactiae)

Answer 57

Neonatal sepsis

Question 58

Prevention for Streptococcus agalactiae

Answer 58

IV ampicillin

Question 59

Previously classified as group D streptococci; are commensal bacteria of the normal enteric microbiota

Answer 59

Enterococci

Question 60

2 most common causes of enterococci infection (EE)

Answer 60

Enterococcus faecalis, Enterococcus faecium

Question 61

Are critical, multidrug-resistant bacteria which are the leading cause of HAIs

Answer 61

ESKAPE pathogens

Question 62

6 ESKAPE pathogens

Answer 62

Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter sp

Question 63

German word for swelling

Answer 63

Quellung

Question 64

Reaction where antibodies bind to bacterial capsule to make it more opaque; diagnosis for Streptococcus pneumoniae

Answer 64

Quellung reaction