Principles of Infectious disease Flashcards
What is the systematic approach for selecting antimicrobial agents
Confirm presence of infection
identify pathogen
select presumptive therapy
therapeutic steps
What does a left shift indicate
Bands (premature neutrophils) in blood > 10%
Bacterial infection
How to confirm presence of infection
H&P exam predisposing factors signs and symptoms - fever - wbc count - esr - crp - procalcitonin - pain and inflammation - disease specific signs and symptoms
what is the range for CRP
.5 - 1 normal
1 - 1.5 moderate inflammation
>10 infection
What is bacteria classified as
Susceptible
intermediate
resistent
What should peak dosage be
2 - 4 x MIC
What factors increase antibiotic resistance
Overuse low dose prolonged exposure inappropriate antibiotics day care
What are requirements for antimicrobial activity
penetrate cell
reach target
kill organism
What are mechanisms of resistance
decreased permeability - porin channels close
drug efflux - pump abx out
drug inactivation - enzymes attack abx
altered target - change ribosomes with CH3 so no binding
what are gram + cocci
Staph
Strep
Enterococcus
What are gram - cocci & cocco-bacilli
H. flu
Neisseria
Moraxella catarrhalis
What are Enterobacteriacea
EKP - e. coli - klebsiella - proteus ESP - enterobacter - serratia - providencia
What are anaerobes
bacteroides fragilis
What is PA
pseudomonas aeruginosa
How to identify pathogen
Stains
Serologies
Culture and sensitivity
What are the stains
Gram Stain - G+ purple (peptidoglycan) - G- pink Acid-fast - mycobacteria - nocardia India Ink - cryptococcus
What are gram stains routinely performed on
CSF for meningitis
Urethral smears for STI
abscesses or effusions
What is the gold standard for identifying bacteria
Cultures
What are the types of antibody and antigen detection
Immunoflorescence
Latex agglutination
Enzyme-linked Immunoassay
What is identified through immunoflorescence
CMV RSV Varicella Treponema pallidum Borrelia burgdorferi