Bugs - Strep, Enterococci

Question 1

what are viridan streptococci?

Answer 1

alpha(partial) and gamma(none) hemolyzers

Question 2

1 bacterial cause of pharyngitis?

Answer 2

streptococcus pyogenes (group a strep)

fever, absence of cough, purulent exudate, cervical lymphadenopathy

Question 3

microbiological/lab characteristics of pneumococci

Answer 3

GP catalase negative alpha-hemolysis susceptible to optochin soluble in bile salts

Question 4

common presentations of streptococci pneumoniae

Answer 4

otitis, sinusitis, bronchitis, pneumonia, meningitis, bacteremia

most common bacterial cause of otitis, meningitis

Question 5

treatment for a pneumococcal meningitis

Answer 5

ceftriaxone and vancomycin

….macrolide if atypical

Question 6

treatment for a pneumococcal otitis

Answer 6

amoxicillin if fever is persistant dont need to treat right away

Question 7

most common species of enterococci how do their treatments differ?

Answer 7

E. faecalis - ampicillin/penicillin are drugs of choice; use ampicillin AND aminoglycoside for endocarditis

E. faecium - vancomycin is drug of choice; resistant to ampicillin; use vancomycin AND aminoglycoside for endocarditis

Question 8

types of patients commonly getting enterococcal UTI

Answer 8

males hospitalized, catheterized pts not common in healthy, non-hospitalized females

Question 9

osler node vs janeway lesion what are these?

Answer 9

osler node is PAINFUL; erythematous nodule on thumb pad

janeway lesion is not paintful; erythematous nodule on hypothenar emminence

Question 10

where do enterococci colonize?

most important virulence factor?

Answer 10

GI tract!

antibiotic resistance is most common virulence factor…comes from antibiotic use affecting microbiome…

Question 11

prevnar

pneumovax

Answer 11

both pneumococcal vaccines

prevnar - given to all children

pneumovax - 65+ y/o

Question 12

most common Group A strep species?

most common Group B strep species?

what determines grouping?

Answer 12

group A - s. pyogenes

group B - s. agalactiae

groups are determined by its common cell wall carbohydrate

Question 13

M protein

Answer 13

virulence factor for s. pyogenes

adhesive - binds many serum proteins including factor H and CD46 on keratinocytes

forms antibodies that react w/cardiac myosin and sarcolemma

strongly antiphagocytic

Question 14

streptolysin O, streptolysin S

Answer 14

hemolysins produced by s. pyogenes

Question 15

pyrogenic exotoxins produced by s. pyogenes

Answer 15

SpeA, SpeC - superantigens; responsible for scarlet fever and toxic shock syndrome; HLA dependent; encoded by bacteriophages

SpeB - cleaves IgG

Question 16

suppurative vs non-suppurative infections of s.pyogenes

Answer 16

suppurative(pus producing):

• pharyngitis(can be complicated by scarlet fever)
• impetigo, erysipelas, necrotizing fasciitis, strep. TSS

non-suppurative:

• rheumatic fever, rheumatic heart disease
• glomerulonephritis

Question 17

treatment options for this?

Answer 17

pharyngitis; GAS(s. pyogenes)

penicillin

if allergic: macrolides, clindamycin

Question 18

scarlet fever

manifestation?

Answer 18

uncommon manifestation of acute infection, usually pharyngitis

manifests from SpeA, SpeC release

rash starts at trunk

capillary fragility

strawberry tongue and peripheral desquamation in later stages

Question 19

what streptococcal subgroup is s. pneumoniae a part of?

Answer 19

the mitis subgroup

Question 20

what are the major/minor criteria for rheumatic fever?

Answer 20

major:

• polyarthritis
• carditis
• chorea
• erythema marginatum
• subcutaneous nodules

minor:

• arthralgia
• fever
• elevated CRP or ESR
• 1st degree heart block

need 2 major or 1 major and 2 minor to declare

Question 21

what MUST you do if you see a pt with streptococcus **bovis **

this is Group __ strep

Answer 21

colonoscopy

s. bovis group(including s.gallolyticus) is a Group D strep that is highly associated with colon cancer

Question 22

treatment for group b strep

Answer 22

penicillin

vancomycin or clindamycin if allergic

Question 23

neonate gets fever in first 4-6 weeks of life

doc orders an LP

what is the doc looking for?

Answer 23

group B strep: s. agalactiae

normally colonizes GI/GU(can be picked up in birthing canal)

sepsis and meningitis are risks for both early and late onset!

Question 24

what infeciton precedes acute rheumatic fever

what is the incubation period

Answer 24

10-30 days following a pharyngitis from a GA-strep infection

Question 25

treatment for s. agalactiae infection?

Answer 25

penicillin

if allergic: vancomycin or clindamycin

screen pregnant women and treat those that are colonized when at term

Question 26

what is the s. milleri group?

what disease manifestation are they associated with?

Answer 26

unofficial name for virdans group of bacterial:

(s. anginosis, s. constellatus, s. intermedius)

can display beta, alpha or gamma hemolysis

unusual propensity to cause abcess - liver, brain, periodontal

angie intermediately looks at constellations