Clinical Correlations: Staphylococal and Streptococcal Infections Flashcards
Clinical thought process
- is the patient infected
- What is the (likely) infecting organism
- Where did it come from
- Where has it gone
B hemolytic streptococci
-list them and if they are OCN S or not
- S. pyogenes (Group A) PCN S.
- S agalactiae (group B) +/- PCN
- S dysgalactine (C&G) +/- PCN
Non B hemolytic Streptococci
S pneumoniae
S gallolyticus
Viridans streptococci
Where is a majority of staphylococcus located
skin
where is streptococcus located
skin, oropharynx, large intestine, small intestine
What can streptococcus pyogenes (GAS) cause
- cellulitis (non-pirulent)
- Pharyngitis
- Impetigo
- Scaret fever
- Rheumatic heart disease
- acute rheumatic fever
- glomerulonephritis
what is the spectrum of illness for other B hemolytic streptococci that aren’t GAS
- GBS: cellulitis (adults); occasional BSI/Endocarditis
- GCS/GGS: cellulitis/BSI
What can streptococcus pneumoniae cause
- Pneumonia (most common)
- Meningitis (most common)
- both could be with or without bacteremia
What is the most common cause of bacterial pneumonia
Streptococcus pneumoniae
What does Viridans group Streptococci cause
- intraabdominal abscess (diverticulitis)
- Head/Neck Infection
- liver abscess
- bacteremia/endocarditis
Spectrum of illness for staphylococcus aureus
-pirulent cellulitis (white head/puss)
-Nosocomial infections
*surgical site infections
(any break in skin)
*Pneumonia (more than community)
*Catheter associated
*Inta-abdominal
-Endocarditis
Coagulase-negative Staphylococci can cause what illnesses
- Nosocomial infections (healthcare associated)
- catheter associated
- surgical site infections
- prosthetic infections
spectrum of illness for Staphylococcus lugdunesis
-clinical manifestations and aggressiveness more akin to S aureus
What is a big indication of necrotizing fasciitis
-usually have pain way out of proportion to the visible swelling
(it is an infection of the subcutaneous tissue)
superantigens
- produced by all pathogenic Staphylococcus aureus isolates (up to 24 distinct)
- Streptococcus pyogenes (GAS) produce up to 11 distinct
- cause activation of up to 50% of T cells (1 in 10,000 more usual antigens)-cytokine storm can result in toxic shock syndrome (TSS)