Micro Flashcards
Infectious proteins that lack nucleic acid
Prions
Normal flora of colon
B fragilis > E coli
Normal flora of upper respiratory tract
Moraxella catarrhalis
Investigation for brain abscess
CT scan with contrast
Infections causing brain abscess
Most commonly viridans streptococci and Staphylococcus aureus.
Multiple brain abscesses are usually from_______; single lesions from _________
bacteremia
contiguous sites:
Best test for detecting acute osteomyelitis is
MRI
______ is the most common site for hematogenous osteomyelitis in adults.
Why?
Vertebral body
due to “cork screw” anatomy of nutrients arteries with age
Site of hematogenous osteomyelitis in children
metaphysis of long bone due to slow blood flow
Pre-treatment with dexamethasone limits inflammation due to _______, but not ______
gram + but not gram -
because gram - lack techoic acid and contain only small amount of peptidoglycan
Single most important measure t reduce risk of transmission of hospital acquired infections
Hand hygiene
Contact precautions for which diseases
MDR organisms (MRSA, VRE) Enteric organisms (C. difficile) Scabies
Airborne (<5nm)
TB
Chickenpox
small pox
Measles
Prophylactic use of vancomycin in CV line passing
↑ risk of VRE
Autoclave
Pressurized steam at > 120°C. Sporicidal. May not reliably inactivate prions.
Alcohols
Denature proteins and disrupt cell membranes. Not sporicidal.
Chlorhexidine
Denatures proteins and disrupts cell membranes. Not sporicidal.
Chlorine
Oxidizes and denatures proteins. Sporicidal.
Ethylene oxide
Alkylating agent. Sporicidal.
Quaternary amines
Impair permeability of cell membranes. Not sporicidal.
Iodine and iodophors
Halogenation of DNA, RNA, and proteins. May be sporicidal.
Hydrogen peroxide
Free radical oxidation. Sporicidal.
Formaldehyde and gluaraldehyde
Alkylating and cross-linking DNA ans proteins. Sterlization of hospital instruments that cannot withstand autoclave temp.
