Exam 1 - Rybakov Flashcards
establishing presence of infection criteria: fever
hallmark of infection
non infectious causes: drug induced
false negatives: antipyretics
establishing presence of infection criteria: systemic s/sx
hypotension
tachycardia
tachypnea
fever
chills
rigor
malaise
mental status
increased or decreased WBC
- over 12k or below 4k or >10% immature forms (bands)
establishing presence of infection criteria: lab test (WBC)
normal: 4,500-11,000
elevated in response to infectious and non-infectious causes
-non infectious: steroids, leukemia, stress, RA, pregnancy
leukocytosis shows increased ________ +/- ______ and is associated with _______ infections
neutrophils, bands, bacterial
lymphocytosis shows increase in ______ and ______ and is associated with _______, _____, or _____ infections
t-lymphocytes, b-lymphocytes, viral, fungal, or tuberculosis
ANC equation (know for NAPLEX but not this exam
ANC = (WBC x (%segs + %bands))/100
neutropenia is ANC __500 cells/mm^3
<
risk of infection (increases/decreases) as ANC decreases
increases
ESR and CRP are (specific/non-specific) markers of infection and are (elevated/lowered) in presence of inflammation
non-specific, elevated
PCT (procalcitonin) is useful in what way?
as a serial measurement every 1-2 days to assess response to therapy and when to d/c abx
radiographic tests to establish infection
x-ray
CT
MRI
nuclear imaging
Echocardiography
identification of the pathogen: microbiological studies
-infected body materials must be sampled, if possible, before initiation of anti-infective therapy
-avoid contamination
type of culture based on infection site
osteomyelitis:
meningitis:
Endocarditis:
bone biopsy
CSF
blood cultures, heart valve tissues
identification of the pathogen: microbiological studies (part 2)
colonization vs infection
colonization: potentially pathogenic organism is present at body site but not invading host tissue
infection: pathogenic organism is present at body site and is damaging host tissue or eliciting host responses and symptoms consistent with an infection
identification of the pathogen: cultures timeline
minutes to hours: retrieve cultures and send to lab
24-48 hrs: plate organism, await growth, gram stain
48-72 hrs: ID and susceptibility testing of organism
rapid diagnostic testing total time requirements
8-15 hrs
rapid diagnostic test for bloodstream infections
PhenoTest BC Kit
BioFire BCID2
ePlex BCID
T2 Bacteria
Verigene
other rapid diagnostic tests
MRSA PCR Nasal Test
BioFire FilmArray Panels
Verigene Panels
susceptibility testing definitions: MIC
lowest antimicrobial concentration that prevents visible growth
categorization of whether an organism is susceptible or not
Breakpoint: tells us the category
Susceptible: “can treat with this ABx”
Susceptible dose dependent: “can treat with this ABx at the right dose”
Intermediate: do not use to treat
Resistant: do not use to treat
non-susceptible: do not use to treat
MIC
lowest antimicrobial concentration that prevents visible growth
(where no growth exists)
rapid tests that test for mecA
BioFire BCID2
ePlex BCID
Verigene
ESR and CRP are (specific/non-specific) markers of infection
non-specific
reasons why WBC might be elevated (besides infection)
steroids
leukemia
stress
RA
pregnancy
