Lecture 4

Question 1

Which Gram (+) cocci is carried in the anterior nares, axilla, perineum, and hands?

Answer 1

Staphylococcus aureus

Question 2

What are the preventative measures to take for Staphylococcus aureus?

Answer 2

-Handwashing
-Education of health personnel
-Aseptic technique in ER and OR wound precaution

Question 3

Which Gram (+) cocci shows up as pustules, boils, conjunctivitis, styes, otitis etc.

Answer 3

Staphylococcus aureus

Question 4

What are the complications of Staphylococcus aureus?

Answer 4

Pneumonia, osteomyelitis, septicemia, endocarditis

Question 5

What are the toxins present in Staphylococcus aureus?

Answer 5

Cytotoxins
Haemolysins
Enterotoxin (A-E) (G-I)
Exfoliative
TSS

Question 6

Which gram (+) cocci is found in 15% of the health population?

Answer 6

Staphylococcus aureus

Question 7

Describe the appearance of Staphylococci.

Answer 7

1 um in diameter
Grape-like clusters

Question 8

Which Staphylococci species are the most important for humans?

Answer 8

Staphylococcus aureus
Staphylococcus epidermis
Staphylococcus saprophyticus

Question 9

How is Staphylococcus aureus grown?

Answer 9

Simple media-blood agar
2-3mm colonies in 24 hrs at 37degrees

Question 10

What toxin can be described as a super antigen and is an important cause of food poisoning symptoms such as nausea, cramps, and diarrhea?

Answer 10

Enterotoxin (A-E) (G-I)

Question 11

What toxin causes scalded skin syndrome in infants?

Answer 11

Exfoliative toxins (ETA, ETB)

Question 12

What was the previous name(s) for TSS toxin?

Answer 12

Pyrogenic exotoxin c and exotoxin f

Question 13

What enzymes are involved in Staphylococcus aureus?

Answer 13

Beta-lactamase (penicillinase)
Coagulase (Coagulation of fibrin)
Hyaluronidase
Staphylokinase

Question 14

What test is used for the main identification of Staphylococcus aureus?

Answer 14

Coagulase Test

Question 15

What is Staphylococcus aureus an important cause of?

Answer 15

acquired nosocomial infections

Question 16

What is the role of bacteriophage types in staphylococcus aureus?

Answer 16

identity markers that trace the source of infection

Question 17

Which Staphylococci is most accurately described as opportunistic?

Answer 17

Staphylococcus epidermis

Question 18

What are the properties of Staphylococcus Epidermis?

Answer 18

Normal skin/mucous flora
Non-pathogenic except in compromised patients

Question 19

How can Staph. epidermis be prevented?

Answer 19

Proper care of patient after operations

Question 20

What are the signs of s. epidermis?

Answer 20

Post-operative infections
Necrotizing enterocolitis in neonates

Question 21

Describe the appearance of streptococci.

Answer 21

Arrangement: Pairs or chains

Question 22

How are streptococci grown?

Answer 22

Blood agar- simple media

Question 23

Describe the haemolytic properties of Streptococci.

Answer 23

Alpha hemolysis- greenish/brown zone of partial RBC destruction

Beta hemolysis- Clear zone of complete RBC destruction around colonies

Non-hemolytic

Question 24

What is extracted from the cell wall and subdivides Streptococci in groups A-T?

Answer 24

Carbohydrate C-antigen

Question 25

What is the role of the M-protein in streptococci?

Answer 25

Permits subdivision of beta-haemolytic streptococci into over 70 serotypes; found almost exclusively in group A. Important virulence factor: antiphagocytic and degrades complement C3b.

Question 26

What is Group A strep called?

Answer 26

S. Pyogenes

Question 27

Is Group A strep alpha-hemolytic?

Answer 27

No- it is beta- Haemolytic

Question 28

What are the signs and symptoms of s. pyogenes?

Answer 28

Fever Strep throat aka acute tonsilitis Skin infections Impetigo, cellulitis Septicemia Puerperal fever

Question 29

What results from complications in acute tonsilitis?

Answer 29

Scarlet fever

Question 30

What are the typical complications experienced from patients with Strep. pyogenes?

Answer 30

acute glomerulonephronitis and rheumatic fever

Question 31

What toxins that cause s. pyogenes?

Answer 31

Streptolysins (O & S) Streptococcal pyrogenic exotoxins (Spes) - Superantigens SpeA, SpeB, SpeC

Question 32

What causes the rash in scarlet fever?

Answer 32

Streptococcal pyrogenic exotoxins

Question 33

What is the primary enzyme involved in s. pyogenes?

Answer 33

Hyaluronidase-splits hyaluronic acid in connective tissue and helps spreading

Question 34

Which strain of strep can be found in 5-10% of healthy people?

Answer 34

pyogenes/group A

Question 35

How can s. pyogenes be prevented?

Answer 35

Education of health personnel and public Aseptic obstetric procedures Early detection and treatment

Question 36

How is s. pyogenes transmitted?

Answer 36

Direct contact Nasal carriers Contaminated food

Question 37

Which strep is sensitive to penicillin G?

Answer 37

Strep. pyogenes

Question 38

What is strep Group B called?

Answer 38

Streptococcus agalactiae

Question 39

Where is strep. agalactiae found?

Answer 39

Vagina of healthy women

Question 40

What are the signs of strep. agalactiae?

Answer 40

Early septicaemia Delayed meningitic form

Question 41

Can s. agalactiae cause neonatal infections?

Answer 41

yes

Question 42

What are the symptoms of s. facealis?

Answer 42

Infections- urinary, septicaemia, endocarditis, endocarditis, meningitis

Question 43

What is Strep group D?

Answer 43

s. facealis

Question 44

How is s. facealis transmitted?

Answer 44

Preys on compromised individuals

Question 45

Where can s. facealis be found?

Answer 45

Normal GI tract

Question 46

Which strep species in found in the oral cavity of healthy people?

Answer 46

Viridans strep

Question 47

Which strep is found in the nasopharynx of healthy people?

Answer 47

Strep. pneumoniae

Question 48

What is another term for strep. pneumoniae?

Answer 48

Pneumonococcus

Question 49

What are the symptoms of pneumonococcus?

Answer 49

Lobar pneumonia and meningitis in infants, elderly and alcholics(lobar)

Question 50

What are the properties of s. pneumoniae?

Answer 50

Polysaccharide capsule with antiphagocytic properties and 90 distinct singular capsules

Question 51

How can s. pneumoniae be prevented?

Answer 51

Social programs Avoiding crowded housing areas Vaccination of at risk populations

Question 52

What are the symptoms/effects of viridans strep?

Answer 52

Endocarditis in ppl w damaged heart valves

Question 53

What are the types of gram (-) cocci?

Answer 53

Neisseria meningitidis and Neisseria gonorrhoeae

Question 54

What properties are the same in both gram (-) cocci?

Answer 54

Diplococci Selective media used for isolation on Thayer Martin plate

Question 55

What are the signs and symptoms of N. meningitidis?

Answer 55

Meningitis Septicaemia Waterhouse-Friedrichsen syndrome

Question 56

Which gram (-) cocci uses a chocolate agar, 5-10% of CO2 and needs to be at a temp. of 37 degrees?

Answer 56

N. meningitidis

Question 57

What is another term for N. meningitidis?

Answer 57

Meningococcus

Question 58

Where is N. meningitidis found?

Answer 58

Nasopharynx of healthy individuals

Question 59

Who primarily transmits N. meningitidis?

Answer 59

Children and military recruits

Question 60

How is N. meningitidis treated?

Answer 60

Penicillin Vaccination

Question 61

How is N. gonorrhoeae treated?

Answer 61

All partners must be treated simultaneously using ceftriaxone, cefixime, ciprofloxacin or ofloxacin in combination with doxycycline or azithromycin.

Question 62

Which gram (-) cocci is resistant to penicillin?

Answer 62

N. gonorrhoeae

Question 63

How is N. gonorrhoeae diagnosed in men?

Answer 63

Urethral discharge swabs observed under microscope *Anal and pharyngeal can also be taken in gay men*

Question 64

How is N. gonorrhoeae diagnosed in women?

Answer 64

Anal, urethral, and endocervical swabs that contain the culture

Question 65

What are the symptoms of N. gonorrhoeae in men?

Answer 65

Acute infection of urethra in 90-95% of men that can escalate to prostatitis and epididymitis when left untreated

Question 66

What are the clinical symptoms of N. gonorrhoeae in women?

Answer 66

Cervicitis in women and can escalate to PID and sterility Note: 50% of women are asymptomatic and is a mom transfers symptoms to baby it can cause neonatal infection

Question 67

What symptom of N/ gonorrhoeae is shared between men and women?

Answer 67

Rectal and pharyngeal infection

Question 68

Who does disseminated Gonococcal Infection affect and what are the symptoms?

Answer 68

1-3% cases of women Fever, skin infection, arthritis

Question 69

Is N. gonorrhoeae sensitive to temperature and damp environments?

Answer 69

Yes

Question 70

What is a causative agent of gonorrhoeae STD?

Answer 70

N. gonorrhoeae

Question 71

How big are the cocci in N. gonorrhoeae?

Answer 71

0.6-1 um

Question 72

What is the second highest STD reported aft. chlamydia?

Answer 72

Gonorrhoeae