Common Infectious Diseases Flashcards
What is the most common cause of cellulitis?
Beta haemolytic streptococci
In what populations should you consider gram negative cellulitis?
Immunocompromised, cirrhosis, chronic leg ulceration
What organisms should be considered in marine exposure cellulitis?
Vibrio/aeromonas species
What organisms should be considered in dog/cat bite infections?
Pasteurella multocida
Capnocytophagia canimorsus
What is required to diagnose a necrotising soft tissue infection?
Surgery
What should be given for recurrent cellulitis?
Penicillin VK 250mg PO BD prophylaxis
When should IV therapy be given for cellulitis?
Sepsis
Comorbidities: obesity, chronic venous insufficiency, peripheral vascular disease, heart failure
Failure of oral antibiotic therapy
What is the most important pharmacodynamic parameter for this dosing regimen of aminoglycosides?
Cmax/MIC – to get high concentrations for rapid killing and then clear drug rapidly to avoid toxicity
What is an extended spectrum beta lactamase?
A bacteria that excretes extracellularly an enzyme which hydrolyses the beta lactam molecule
What are ESBLs resistant to?
3rd generation cephalosporins
What type of bacteria are ESBLs?
Aerobic gram negative bacilli (e.g. E coli, klebsiella pneumoniae)
What is the mechanism of resistance of ESBLs?
Plasmid mediated
What is the most common ESBL genotype?
CTX-M
Which bacteria have the ampC gene?
ESCAPPM organisms
What is the treatment for ESBLs?
Carbapenems
What is fosfomycin?
An oral carbapenem
What is the most common cause of pneumonia?
Strep pneumoniae
