Trends of 9,416 multidrug-resistant Gram-negative bacteria.

OBJECTIVE: a resistance of hospital-acquired bacteria to multiple antibiotics is a major concern worldwide. The objective of this study was to investigate multidrugresistant (MDR) bacteria, clinical specimens, origin of specimen and trends, and correlate these with bacterial sensitivity and consumption of antimicrobials. METHODS: 9,416 bacteria of nosocomial origin were evaluated in a tertiary hospital, from 1999 to 2008. MDR was defined for Gram-negative bacteria (GNB) as resistance to two or more classes/groups of antibiotics. RESULTS: GNB MDR increased by 3.7 times over the study period (p<0.001). Acinetobacter baumannii was the most prevalent (36.2%). Over the study period, there were significant 4.8-fold and 14.6-fold increases for A. baumannii and K. pneumoniae (p<0.001), respectively. Sixty-seven percent of isolates of MDR GNB were isolated in intensive care units. The resistance of A. baumannii to carbapenems increased from 7.4 to 57.5% during the study period and concomitant with an increased consumption. CONCLUSION: that decade showed prevalence of GNB and a gradual increase in MDR GNB. There was an increase in carbapenem resistance of 50.1% during the study.

Trends of 9,416 multidrug-resistant Gram-negative bacteria / Evolução de 9.416 bactérias Gram-negativas multirresistentes.

Summary Objective: a resistance of hospital-acquired bacteria to multiple antibiotics is a major concern worldwide. The objective of this study was to investigate multidrugresistant (MDR) bacteria, clinical specimens, origin of specimen and trends, and correlate these with bacterial sensitivity and consumption of antimicrobials. Methods: 9,416 bacteria of nosocomial origin were evaluated in a tertiary hospital, from 1999 to 2008. MDR was defined for Gram-negative bacteria (GNB) as resistance to two or more classes/groups of antibiotics. Results: GNB MDR increased by 3.7 times over the study period (p<0.001). Acinetobacter baumannii was the most prevalent (36.2%). Over the study period, there were significant 4.8-fold and 14.6-fold increases for A. baumannii and K. pneumoniae (p<0.001), respectively. Sixty-seven percent of isolates of MDR GNB were isolated in intensive care units. The resistance of A. baumannii to carbapenems increased from 7.4 to 57.5% during the study period and concomitant with an increased consumption. Conclusion: that decade showed prevalence of GNB and a gradual increase in MDR GNB. There was an increase in carbapenem resistance of 50.1% during the study. .

Resumo Objetivo: a resistência bacteriana hospitalar a múltiplos antibióticos é uma grande preocupação mundial. O objetivo deste estudo foi conhecer os agentes multidroga-resistentes (MDR), materiais clínicos, origem e evolução, e correlaciona-los à sensibilidade bacteriana e ao consumo de antimicrobianos. Métodos: foram avaliadas 9.416 bactérias de origem nosocomial, em um hospital terciário, durante o período de 1999 a 2008. Foram definidas como MDR as bactérias Gram-negativas (BGN) que apresentaram resistência a duas ou mais classes/grupos de antibióticos. Resultados: as BGN MDR tiveram um aumento global de 3,7 vezes no final do período (p<0,001). O Acinetobacter baumannii foi o mais prevalente (36,2%). Durante o período do estudo, houve um aumento significativo de 4,8 e 14,6 para A. baumannii e K. pneumoniae (p<0,001), respectivamente. Sessenta e sete por cento das BGN MDR foram isoladas em unidade de terapia intensiva. A resistência do A. baumannii aos carbapenêmicos aumentou de 7,4 para 57,5% durante o período, concomitante ao aumento do consumo. Conclusão: durante essa década, houve uma prevalência de BGN e um aumento gradual das BGN MDR. Houve um aumento da resistência aos carbapenêmicos de 50,1% durante o estudo. .

Trends in bacterial resistance in a tertiary university hospital over one decade.

The objective of this study was to investigate bacterial resistance trends, infection sites and the relationship between resistance and admittance to the intensive care unit (ICU). A total of 53,316 bacteria identified between 1999 and 2008 were evaluated. Multidrug resistance was characterized when gram-negative bacilli (GNB) presented resistance to two or more classes of antibiotics. Gram-positive cocci (CPC) were assessed for resistance to penicillin, oxacillin and vancomycin. GNB were the most common (66.1%) isolate. There was a 3.7-fold overall increase in multidrug resistant GNB over the study period; Acinetobacter baumanii and Staphylococcus aureus were the most prevalent. Highest increases were recorded for Klebsiella pneumoniae (14.6-fold) and enterococci (73-fold). The resistance rates for GNB and GPC were 36% and 51.7%, respectively. Most multidrug resistant GNB and GPC were recovered from ICU patients (p-value<0.001). Vancomycin-resistant enterococci were isolated during this decade with an increase of 18.7% by 2008. These data confirm the worldwide trend in multidrug bacterial resistance.