Antimicrobial drugs Flashcards
Staphylococcus aureus gram stain
Gram positive cocci
Staphylococcus aureus
Normal flora of Skin, nose, throat
Staphylococcus aureus cause?
Disease some resistant to methicillin Methicillin(resistant Staphylococcus aureus (MRSA)
Specific type of staph that is resistant to beta-lactams
MRSA
Two type of MRSA
Health-associated MRSA
Community-associated MRSA
Healthcare associated MRSA
Resistant to many different chemotherapeutic agents
Used to be more prevalent
Community-associated MRSA
Resistant to fewer chemotherapeutic agents
Rise in # of cases
MRSA causes
Skin infections
MRSA transmission
Direct contact
Fomites
MRSA Signs/Symptoms
Red bump on skin (may be swollen/painful, warm, filled with pus)
Fever
MRSA Dx
Culture
Nucleic acid identification
MRSA Tx
Vancomycin?
VRSA
Glycylcyclines?
Should do susceptibility testing first
Pseudomonas gram stain
Gram-negative rod
Pseudomonas
Can utilize unusual carbon sources Can grow in soap/antiseptics Resistant to many chemotherapeutic agents
Main mechanism of resistance = efflux pumps Most clinically relevant: Pseudomonas aeruginosa
Pseudomonas aeruginosa produce?
blue/green pigment
Common hospital-acquired infection
Commonly infects burns/wounds
Pseudomonas aeruginosa causes
Wound/burn infections Bacteremia Ear infections UTIs Respiratory infections Dermatitis
Pseudomonas aeruginosa Pathogenesis
Produces exoenzymes: cleave collagen and interfere with fibrin formation
Contains LPS—endotoxin—released when cell is
lysed -> severe drop in blood pressure ->
blood/oxygen can’t reach organs
Produces Toxin A: inhibits protein synthesis -> cell death
Produces hemolysins: lyse RBCs
Pseudomonas aeruginosa Diagnosis
Culture
Pseudomonas aeruginosa Treatment
Carbenicillin? Carbapenems? Gentamicin? Polymyxin E? Should do susceptibility testing to confirm
