2016. Antibiotic Susceptibility of Streptococcus pneumoniae To The Most Frequently Prescribed Antibiotics By Region In The USA in 2014
Session: Poster Abstract Session: Antimicrobial Resistant Infections: Treatment
Saturday, October 29, 2016
Room: Poster Hall
Posters
  • ID Week 2016 Tillotson G poster 2016 Antibiotic Susceptibility in US of S pneumoniae 2014.pdf (464.8 kB)
  • Background: 

    Streptococcus pneumoniae is the most common cause of community-acquired bacterial pneumonia (CABP). Resistance to empirically prescribed antibiotics is a continuing major issue. 

    Methods:

    715 isolates of Streptococcus pneumoniaewere collected from laboratories across the 9 CDC Census regions of the USA in 2014. Susceptibility to the antibiotics listed in the table below was tested according to CLSI M-24.

    Results: 

    715 isolates were collected in 2014. Rates of resistance ranged from 48.8% in the case of azithromycin, 24.1% with tetracycline and 7.3% in the case of ceftriaxone. All isolates had a MIC to solithromycin of ≤0.25mg/l. Additionally resistance rates by drug by region were also reported.

     

    Antimicrobial Agent

    MIC50

    MIC90

    Range

    CLSIa

    %S

    %I

    %R

    Solithromycin

    0.008

    0.25

    0.002 — 1

    -

    -

    -

    Azithromycin

    0.25

    >32

    0.03 — >32

    51.3

    0.3

    48.4

    Ceftriaxone

    ≤0.06

    1

    ≤0.06 — 8

    80.8

    11.9

    7.3c

    92.7

    6.0

    1.3b

    Penicillin

    ≤0.06

    2

    ≤0.06 — 8

    57.2

    29.5

    13.3d

    57.2

    -

    42.8e

    92.7

    6.3

    1.0f

    Tetracycline

    ≤0.5

    >8

    ≤0.5 — >8

    75.2

    0.7

    24.1

    Trimethoprim-Sulfamethoxazole

    ≤0.5

    >4

    ≤0.5 — >4

    69.1

    12.2

    18.7

     

    aCLSI 2015 criteria; bUsing non-meningitis breakpoints; cUsing meningitis breakpoints; dUsing Oral breakpoints; eUsing parenteral meningitis breakpoints; fUsing parenteral non-meningitis breakpoints

    Conclusion: 

    Although current guidelines recommend macrolides and tetracyclines as empiric options for the treatment of out-patient, low risk CABP, almost half of all Streptococcus pneumoniaestrains in the USA are resistant to currently approved macrolides. Resistance and drug-related factors such as tolerability should be considered during empiric selection of antibiotics for CABP.

    Glenn Tillotson, PhD, Cempra Inc., Chapel Hill, NC

    Disclosures:

    G. Tillotson, Cempra: Employee , Salary

    Findings in the abstracts are embargoed until 12:01 a.m. CDT, Wednesday Oct. 26th with the exception of research findings presented at the IDWeek press conferences.