Session: EV028 Surveillance - global
Category: 3b. Resistance surveillance & epidemiology: Gram-negatives
22 April 2017, 08:45 - 15:30
EV0531
Epidemiology and antimicrobial susceptibility trends of Gram-negative aerobic
bacteria causing intra-abdominal infections in Latin America between 2006-2015
Elisa Maria Beirao*1, Maria Rita Elmor2, Flavia Rossi3, Juvencio Furtado4, Marines Martinho5,
Adriana Pires6, Fernando Serra7, Roberto Muniz Junior8
1Complexo
2Hospital
Hospitalar Edmundo Vasconcelos
Beneficiencia Portiuguesa
3Hcfmusp
4Hospital
Heliopolis
5Hospital
Albert Einstein
6Universidade
7Msd;
Federal Do Rio de Janeiro
Instituto de Infectologia Emilio Ribas
8Msd
Background: Regional epidemiological data and resistance profiles are essential for selecting
appropriate antibiotic therapy for intra-abdominal infections (IAIs). Study for monitoring antimicrobial
resistance trends (SMART) surveillance program monitors the epidemiology and trends in antibiotic
resistance of intra-abdominal pathogens to currently used therapies. The current report describes such
trends between 2006 and 2015.
Material/methods: Participating sites, in ten Latin America countries, collected each up to 100
consecutive, non selected isolates of Gram-negative aerobic bacilli from intra-abdominal infections
between 2006 and 2015. Infections were classified as hospital-associated (HA) if the hospital length of
stay (LOS) at the time of specimen collection was ≧48 hour. Confirmation of identification and
susceptibility testing were performed in a central laboratory (IHMA). Minimum inhibitory concentrations
(MICs) to 12 antibiotics and production of extended spectrum beta-lactamase (ESBL) were determined
using custom MicroScan panels (Siemens Medical Solutions Diagnostics, West Sacramento, CA),
following CLSI breakpoints. A database was created with the collected data and processed by means
of descriptive statistics. For the Linear Trends in susceptibility and ESBL rates were used: Chi-square
for comparison between the proportions; linear Regression for estimation curves; time trend analyses.
All analyzes were performed using SPSS (21.0) and p <0.05 was set as significance level.
Results: A total of 10,897 Gram-negative clinical isolates from intra-abdominal infections in Latin
America were analyzed. Of 89 different species, the most common was Escherichia coli (41.69%),
followed by Klebsiella pneumoniae (16.94%) and Pseudomonas aeruginosa (9.42%). Isolates were
from multiple intra-abdominal sources of which 45,86% were peritoneal fluid, 20,62% were intraabdominal abscesses, and 7,20% were gall bladder infections. Ertapenem, imipenem and amikacin
had greatest activity against gram-negative bacteria. E. coli susceptibility trends remained stable for
antibiotics tested in the studied period. Acinetobacter baimannii showed the greatest resistance profile
to antimicrobials tested, relative to other gram-negative bacteria. Trend analysis determined that
resistance to imipenem and ertapenem increased significantly among K. pneumonia, p=0.006 and
p=0.012 respectively. Susceptibility trends increased significantly to cefepime (p=0.004), piperacillintazobactam (p=0.002) and imipenem (p=o,02) among P. aeruginosa.
Conclusions: Selection of appropriate empiric antibiotic therapy is critical for preventing unnecessary
morbidity and mortality from IAIs. Monitoring antibiotic susceptibility trends is required for
understanding the role of available antibiotics on the treatment of infections as intra-abdominal
infections