Lecture 1: Antibiotic choices in primary care Flashcards
Which bacteria are gram positive?
Strep pneumoniae (aka Pneumococcus) Strep group A beta hemolyticus (aka Strep pyogenes) Staph aureus (MSSA, MSRA)
Which bacteria are gram negative?
Hemophylus influenza (H.flu) Pseudomonas E.coli Proteus Klebsiella
Which bacteria are atypical?
Mycoplasma Chlamydia pneumoniae (C. pneumoniae)
What characteristics are unique to gram positive bacteria?
thick wall (that can be stained)
What characteristics are unique to gram negative bacteria?
thin wall (can be stained) mostly bacteria that live in colon- except H. influenza (lives in nasopharynx) and pseudomonas (skin “bully”- attacks weak, immunocompromised/ anatomical problems- never attacks normal, healthy patients)
What characteristics are unique atypical bacteria?
no walls (cannot be stained). Intracellular organisms; they can be atypical regardless of presentation of illness- just depends on the bacteria causing illness.
What bacteria will cause pharyngitis?
Strep group A beta hemolyticus (aka streptococcus pyogenes)
What bacteria will cause otitis media and sinusitis and pneumonia?
Strep pneumoniae (aka pneumococcus) or H. Influenzae (they are BFF) so when treating these things, you need coverage for both gram +/-
What things can be caused by strep group A/ strep pyogenes?
strep pharyngitis, skin infections, rheumatic fever and post-streptococcal glomerulonephritis
What other things can be caused by strep Pneumoniae?
pneumonia and meningitis
Why do we treat strep pharyngitis?
to prevent rheumatic fever
Strep pneumoniae causes?
sinusitis, otitis and pneumonia BUT NOT pharyngitis
How does rheumatic fever occur?
antibodies that were produced to kill strep pyogenes will also attack proteins in the heart because they are structurally similar and cause RF. Antibody- mediated reaction
strep pyogenes also causes what (other than pharyngitis) that can lead to what?
skin infections that can lead to post-streptococcal glomerulonephritis (abx will not reduce risk of getting this)
What is the most common bacteria that causes pneumonia?
Strep pneumoniae
Which bacteria causes pneumonia?
strep pneumoniae (gram +) H. flu (gram -) mycoplasma (atypical) chlamydia pneumonae (atypical) *so when treating PNA, need to cover for all 3 groups
What is #1 cause of death in US in terms of infectious diseases?
pneumonia
strep pneumoccocal vaccine good at protecting against what? and not good at protecting against what?
good for preventing invasive disease (bacteria that spread to places it isn’t in normally like meninges or blood) but not too good at preventing non invasive disease like sinusitis, otitis
skin infections only caused by what type of bacteria?
gram positive
With skin infections, what is the difference between Strep. spp (group A, B) and Staph spp ( MSSA, MRSA)?
strep is non- purulent, MRSA is purulent
What infections can be caused by Strep. spp (group A, B) or Staph spp ( MSSA, MRSA)?
Skin infections Osteomyelitis Septic joint Endocarditis Otitis externa Conjunctivitis
Otitis externa ( in swimmers) and conjunctivitis (in contact lenses wearers) are also associated with what bacteria?
Pseudomonas- the bully that loves water
bacteria found in the colon include?
E.coli
Proteus
Klebsiella
these bacteria (E.coli, Proteus, Klebsiella) cause what infections?
Cystitis Pyelonephritis Prostatitis Diverticulitis Cholecystitis Cholangitis
What antibiotic is most narrow and covers only strep pyogenes?
PCN
This antibiotic covers strep pyogenes and some strains of gram negatives- E. Coli , Proteus, and H. flu
Amoxicillin (can be used for UTI in pregnant women and also for children with otitis media because it covers for h. flu)
side effects of PCN/ amoxil?
rash and diarrhea
Can PCN/ amoxil can be given in pregnant women, lactating women and children?
yes
Amoxicillin w/ clavulanate covers what?
Gr+ (only Strep) , Gr– (H.flu, Moraxella)