Infectious Disease Flashcards
empiric abx coverage: CAP
azithromycin (po)
ceftriaxone and azithromycin (IV)
OR
moxifloxacin (PO and IV)
empiric abx coverage: HCAP
vancomycin and Pip/Tazo
OR
Linezolid/Meropenem
empiric abx coverage: UTI
amoxicillin (1st line) nitrofurantoin (if PCN allergy) TMP-SMX (if no ckd) cipro (ambulatory pyelonephritis) ceftriaxone (pyelonephritis)
empiric abx coverage: skin
MRSA: vancomiycin -> clinda
MSSA: nafcillin
strep: PCNs
empiric abx coverage: GI
ciprofloxacin + metronidazole
OR
ampicillin, gentamycin, metronidazole
empiric abx coverage: C. diff
mild: po vanc
severe: po vans + IV metronidazole
recurrent: po fidaxomicin
principles of antibiotics test taking
convenience antibiotics are almost always wrong
- ceftriadxone, metronidazole
the stuff the ED always uses will be wrong
- ceftriaxone, vancomycin+pip/tazo
the test will give you a reason for why one of these can’t be used or give you an option that has alternates
alternate for vanc
linezolid
alternate for pip/tazo
meropenem, cefepime
alternate for ceftriaxone
ceftazidime
alternate for cipro
ampicillin-gentamycin
HIV path
CXCR4 and CCR5 receptors
Gp120
RNA virus
reverse transcriptase
HIV pt
opportunistic infections
acute retroviral syndrome (flu)
HIV dx
3rd-gen ab test: if + -> western blot OR 4th gen ag-ab, confirmation built in THEN viral load and CD4 count
HIV tx
2+1: 2 nucleoside reverse transcriptase-i AND 1 non-nucleoside reverse transcriptase-i OR 1 protease inhibitor/ritonavir OR 1 fusion inhibitor OR 1 integrase inhibitor
HIV f/u
CD4 climbs 50/yr
viral load fall 1 log in 4wks
ppx to exposure HIV
Pre-exposure ppx - emtricitabine + tenofovir Post-exposure ppx - emtricitabine + tenofovir +/- raltegravir pregnancy - AZT
HIV opportunistic infections: PCP
CD4 < 200
TMP-SMX (1st line ppx)
dapsone (2nd line ppx)
atovaquone (G6PD, sulfa allergy)
HIV opportunistic infections: toxo
CD4 < 100
TMP-SMX
HIV opportunistic infections: MAC
CD4 < 50
azithromycin ppx
HIV opportunistic infections: HHV-8
kaposi’s sarcoma
purple lesion anywhere on the skin
HIV opportunistic infections: candida
oropharynx: nystatin swish & spit (no systemic therapy)
esophagus: fluconazole (systemic therapy for AIDS defining)
TB path
acid fast bacillus
spread through cough
caveating granulomas
TB pt
asx screen
OR
1st exposure = pneumonia = fever + cough
reactivation = fever, hemoptysis, weight loss, Gohn’s complex
TB risk
homeless
foreign travel
prsion
TB dx
asx screen (PPD or Interferon) - PPD ... read at 48-72hrs --5mm immunocompromised --10mm health care workers --15mm soccer moms -γ-interferon --positive or negative cxr = cavitary lesions, granulomsa AFB smears + isolation
TB tx
if AFB + = RIPE
if AFB - but cxr + = isoniazid + B6
if AFB - and cxr - = isoniazid + B6
TB f/u
ignore bcg vaccine (pick γ-interferon if asked to choose)
never PPD if ever the ppd is positive
if AFB +, but weeks later it turns out to be MAC, tx as MAC
RIPE therapy
Rifampin
Isoniazid (INH)
Pyrazinamide
Ethambutol
rifampin side effects
turns body fluids Red
Isoniazid (INH)
B6 deficiency, Neuropathy
always give B6 ppx
Pyrazinamide
hyperuricemia
Ethambutol
eye, color vision disturbance
SIRS criteria
Temp > 38 or < 36
WBC >12 or <4
HR > 90
RR > 20
Severity: SIRS
2/4 SIRS criteria
severity: sepsis
SIRS + source of infection
severity: severe sepsis
sepsis + decrease BP/increase lactate
responsive to volume
severity: septic shock
sepsis + decrease BP/increase lactate
unresponsive to volume
(unit, pressers)
early goal directed therapy for sepsis
CVP 8-12
MAP >65
U output >0.5cc/kg/hr
SvO2 >70%
actions for sepsis
antibiotics and fluids pressors lactate oxygen source control
who gets antibiotics and fluids with sepsis
everyone, within 6hrs
empiric abx
30cc/kg IVF bolus LR = NS
who gets pressors with sepsis
if in shock
1 = norepinephrine
2 = vasopressin
3 = steroids
lactate and sepsis
trend lactate for clearance
oxygen and sepsis
improve oxygen delivery to tissues
source control sepsis
remove plastic (lines, catheter) and drain abscesses
meningitis path
bacterial
meningitis pt
fever and headache
stiff neck
meningitis dx
1st and best: LP
shows many neutrophils
meningitis tx
ceftriaxone (everyone)
vancomycin (everyone)
steroids (“everyone”)
ampicillin (immunocompromised)
meningitis f/u
syphilis: VDRL, RPR in CSF -> IV PCN
lyme: lyme Ab in CSF -> ceftriaxone
TB: AFB + -> RIPE
Cryptococcus => crypto antigen (not india ink) -> amphotericin
RMSF: RMSF antibody -> ceftriaxone
FAILS for meningitis
if FAILS: abx first, then CT, then LP
if NOT fails: LP first, then abx
Focal neurologic deficit Altered mental status Immunocompromised Lesion over site of LP Seizures
abscess/mass path
mass effect
abscess/mass pt
fever and headache
focal neurologic deficit
abscess/mass dx
1st: CT scan w abx
if AIDS and toxo Ag+ -> treat toxo
- pyrimethamine-sulfadiazine and rescan
if NOT AIDS or NOT toxo Ag + -> biopsy
abscess/mass tx
abscess = abx cancer = chemo and radiation
abscess/mass f/u
repeat CT for toxo
- shows improvement, continue
- if not, bx
encephalitis path
viral, infection of parenchyma
encephalitis pt
fever and headache
AMS
encephalitis dx
1st: CT scan w abx
best: LP = lymphocytes
- get HSV PCR
encephalitis tx
herpes with acyclovir
encephalitis f/u
flaccid paralysis = west nile
temporal lobe = herpes encephalitis
bronchitis path
a ‘not that bad’ pneumonia
bronchitis pt
fever and a cough
sputum production
bronchitis dx
cxr = no consolidation (normal)
bronchitis tx
doxycycline, azithromycin
pneumonia path HCAP
dialysis, hospitalized, nursing home
risk for MRSA and pseudomonas
pneumonia path CAP
no HCAP risk, usual bugs
S. pneumo, M. catarrhalis, H. flu