Both the Infectious Disease Society of America (IDSA) and American Thoracic Society
(ATS) advocate obtaining two sets of blood cultures prior to initiating antibiotic therapy
Coagulase-negative staphylococci is a contaminant in blood cultures about 82% of the
time11
The difference between blood cultures before the initiation of antibiotics and after the
initiation of antibiotics in identifying a pathogen is 40% versus 18.7%4
Appropriate blood cultures, allows for prompt identification of the offending organisms
which influences diagnosis, therapy, and prognosis when positive
Pearl #5: Empiric antibiotics for acute uncomplicated cystitis have changed5
Nitrofurantoin monohydrate/macrocrystals 100mg BID for 5 days is the appropriate
choice for empiric therapy of urinary tract infection
Trimethoprim-sulfamethoxazole 160/800mg BID for 3 days is an appropriate empiric
choice if local resistance rates of uropathogens do not exceed 20% (expert opinion)
Fosfomycin trometamol 3g in a single dose is an appropriate empiric choice for urinary
tract infection, but may be inferior efficacy compared to standard short-course regimens
Pivmecillinam 400mg BID for 3 – 7 days is also an appropriate empiric antimicrobial
agent where available
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Fluoroquinolones (ofloxacin, ciprofloxacin, and levofloxacin) should be considered
alternative antimicrobials for acute uncomplicated cystitis
Amoxicillin or ampicillin should not be used for empirical treatment due to resistance to
these agents
Pearl #6: The loading dose of vancomycin is 25 – 30mg/kg based on actual body weight