Fatores de risco para colonização por bactérias hospitalares multiresistentes em pacientes críticos, cirúrgicos e clínicos em um hospital universitário brasileiro / Risk factors for colonization by multiresistant hospital bacterias in critical, surgical and clinical patients in aBrazilian university hospital

Objetivos: avaliar os fatores de risco intrínsecos e extrínsecos associados à colonização por microrganismos resistentes aos antibióticos em pacientes clínicos, cirúrgicos e críticos internados no Hospital de Clínicas da Universidade Federal de Uberlândia (HC-UFU). Casuística: foi realizado um estudo em pacientes colonizados (n=78) e não-colonizados (n=155), incluindo pacientes clínicos (n=126), cirúrgicos (n=72) e críticos (n=35), com idade média de 56,5 anos e tempo de internação de 10,5 dias. A pesquisa de colonização foi realizada na narina e intestino a partir da coleta de material com auxílio de swab e o cultivo primário em meios de ágar MacConkey contendo 2 µg/mL de ceftazidima e ágar manitol salgado com 6 µg/mL de oxacilina. A multirresistência foi caracterizada pelo teste de difusão com disco. Foi preenchida uma ficha individual contendo dados demográficos, fatores de risco intrínsecos e extrínsecos e uso de antimicrobianos. Resultados: no total, aproximadamente 35,0% dos pacientes estavam colonizados; 39,7% estavam colonizados por estafilococos e 35,9% por bacilos gram-negativos (multirresistentes). Os pacientes críticos representaram 54,3% do total. Os fatores de risco associados à presença desses microrganismos incluíram: internação igual ou superior a sete dias (p<0,0001; OR=7,97; IC=3,54-18,47); uso de antibióticos(p=0,003; OR=2,38; IC=1,31-4,32), uso de ? 2 antibióticos (p=0,0004; OR=2,83; IC=1,54-5,21); e internação na Unidade de Terapia Intensiva (p=0,008; OR=2,80; IC=1,27-6,19). Conclusção: a taxa de colonização dos pacientes por Staphylococcus aureus e bacilos gram negativo resistentes foi alta e associada principalmente ao uso de antibióticos e internamento na UTI.

Objectives: to evaluate the intrinsic and extrinsic risk factors related to the colonization by antibiotics resistant microorganisms in clinical, surgical and critical patients in the Hospital de Clínicas da Universidade Federal de Uberlândia (HC-UFU). Casuistic:"a study was carried out in colonized (n=78) and non-colonized (n=155) patients, included clinical (n=126), surgical (n=72) and critical (n=35) patients, with average age 56,5 years and hospital treatment for 10,5 days. The colonization research was carried out in the nostrils and intestine from material collection with the aid of a ?swab? and the primary cultivation in MacConkey agar environment containing 2 µg/mL of ceftazidime and Manitol agar salty with 6 µg/mL of oxaciline. The multirresistance was found by the diffusion test with disk. An individual card was filled in with demographic data, intrinsic and extrinsic risk factors and use of antimicrobials. Results: in the total, approximately 35,0% of the patients were colonized; 39,7% were colonizedby Staphylococcus and 35,9% by gram-negative bacilli (multirresistant). The critical patients represented 54,3% of the total. The risk factors related to the presence of thesemicroorganisms included: internment equal or over seven days (p<0,0001; OR=7,97; IC=3,54-18,47); use of antibiotics (p=0,003; OR=2,38; IC=1,31-4,32), use of ? 2 antibiotics (p=0,0004; OR=2,83; IC=1,54-5,21); and internment in theIntensive Therapy Unit (p=0,008; OR=2,80; IC=1,27-6,19). Conclusion: patients? colonization rate by resistant Staphylococcus aureus and gram negative bacilli was high and related mainly to the use of antibiotics and UTI internment.

Nosocomial outbreak by imipenem resistant metallo - â - lactamase-producing Pseudomonas aeruginosa in an adult intensive care unit in a Brazilian teaching hospital

Objetivo: Describir un brote causado por Pseudomonas aeruginosa resistente a imipenem productora demetallo-b-lactamasa(MBL), tipo de bla de la enzima, con transmisión horizontal de la muestra epidémica en pacientes ingresados en una unidad de cuidados intensivos para adultos mixta. Métodos: Durante el período comprendido entre noviembre de 2003 y julio de 2005, se realizó un estudio de casos y controles en el que se incluyó a 47 (casos) y 122 (control)pacientes en una unidad de cuidados intensivos para adultos mixta, de un hospital universitario de Uberlândia (Minas Gerais [Brasil]). Se analizaron los sitios de la infección, los factores de riesgo, la mortalidad total, la susceptibilidad a los antibióticos, la producción del tipo MBL ,de la enzima y de la diversidad clonal. Resultados: En la mayoría de los pacientes (94%) se detectó una relación temporal/espacial. El índice demortalidad total fue del 55,3%y la neumonía era la infección predominante(85%). La mayoría de las cepas(95%) era resistente a imipenem y a otros antibióticos, excepto al polimixiny la producción de MBL(76,7%). Únicamente se identificó bla SPM 1 en los 15 especímenes analizados. Además, se detectaron 4clones,conpredominio del clon A(61,5%) y B(23,1%). En análisis multivariados, la vejez, la ventilación mecánica, la traqueotomía y el uso previo del carbapenem son factores de riesgo significativos para el desarrollo de la infección de P. aeruginosa resistente a imipenem (AU)

Objective: To describe an outbreak of imipenem-resistant metallo-â-lactamase-producing Pseudomonas aeruginosa, enzyme type bla, by horizontal transmission in patients admitted to a mixed adult ICU. Methods: A case-control study was carried out, including 47 patients (cases) and 122 patients (control) admitted to the mixed ICU of a university hospital in Minas Gerais, Brazil from November 2003 to July 2005. The infection site, risk factors, mortality, antibiotic susceptibility, metallo-â-lactamase (MBL) production, enzyme type, and clonal diversity were analyzed. Results: A temporal/spatial relationship was detected in most patients (94%), overall mortality was 55.3%, and pneumonia was the predominant infection (85%). The majority of isolates (95%) were resistant to imipenem and other antibiotics, except for polymyxin, and showed MBL production (76.7%). Only bla SPM-1 (33%) was identified in the 15 specimens analyzed. In addition, 4 clones were identified, with a predominance of clone A (61.5%) and B (23.1%). On multivariate analysis, advanced age, mechanical ventilation, tracheostomy, and previous imipenem use were significant risk factors for imipenem-resistant P. aeruginosa infection. Conclusions: Clonal dissemination of MBL-producing P. aeruginosa strains with a spatial/temporal relationship disclosed problems in the practice of hospital infection control, low adherence to hand hygiene, and empirical antibiotic use (AU)

Nosocomial outbreak by imipenem-resistant metallo-beta-lactamase-producing Pseudomonas aeruginosa in an adult intensive care unit in a Brazilian teaching hospital.

OBJECTIVE: To describe an outbreak of imipenem-resistant metallo-beta-lactamase-producing Pseudomonas aeruginosa, enzyme type bla, by horizontal transmission in patients admitted to a mixed adult ICU. METHODS: A case-control study was carried out, including 47 patients (cases) and 122 patients (control) admitted to the mixed ICU of a university hospital in Minas Gerais, Brazil from November 2003 to July 2005. The infection site, risk factors, mortality, antibiotic susceptibility, metallo-beta-lactamase (MBL) production, enzyme type, and clonal diversity were analyzed. RESULTS: A temporal/spatial relationship was detected in most patients (94%), overall mortality was 55.3%, and pneumonia was the predominant infection (85%). The majority of isolates (95%) were resistant to imipenem and other antibiotics, except for polymyxin, and showed MBL production (76.7%). Only bla SPM-1 (33%) was identified in the 15 specimens analyzed. In addition, 4 clones were identified, with a predominance of clone A (61.5%) and B (23.1%). On multivariate analysis, advanced age, mechanical ventilation, tracheostomy, and previous imipenem use were significant risk factors for imipenem-resistant P. aeruginosa infection. CONCLUSIONS: Clonal dissemination of MBL-producing P. aeruginosa strains with a spatial/temporal relationship disclosed problems in the practice of hospital infection control, low adherence to hand hygiene, and empirical antibiotic use.

Ventilator-associated pneumonia in an adult clinical-surgical intensive care unit of a Brazilian university hospital: incidence, risk factors, etiology, and antibiotic resistance.

The objective of this study was to evaluate clinical characteristics, etiology, and resistance to antimicrobial agents, among patients with ventilator-associated pneumonia (VAP). A case study vs. patients control under mechanical ventilation and hospitalized into clinical-surgical adults ICU of HC-UFU was performed from March/2005 to March/2006. Patients under ventilation for over 48 h were included in the study including 84 with diagnosis of VAP, and 191 without VAP (control group). Laboratory diagnosis was carried out through quantitative microbiological evaluation of tracheal aspirate. The identification of pathogens was performed by classical microbiological tests, and the antibiotics sensitivity spectrum was determined through the CLSI technique. VAP incidence rate over 1,000 days of ventilation was 24.59. The mean (+/- SD) duration of mechanical ventilation prior to VAP diagnosis was 23.2 +/- 17.2 days. By multivariate analysis the risk factors predisposing for VAP were: mechanical ventilation time and mechanical ventilation > seven days, tracheostomy and use of > or = three antibiotics. Mortality rate was high (32.1 %) but lower than that of the control group (46.5%). Major pathogens were identified in most of patients (95.2%) and included: Pseudomonas aeruginosa (29%), Staphylococcus aureus (26%), Enterobacter/Klebsiella/Serratia (19%) and Acinetobacter spp. (18%), with expressive frequencies of P. aeruginosa (52%), S. aureus (65.4%) and Enterobacteriaceae (43.7%) resistant to imipenem, oxacillin and 3/4 generation cephalosporins, respectively. In conclusion, our observation showed VAPs caused by multiresistant microorganisms, the prescription of > or = three antibiotics, and mortality with unacceptably high rates. The practice of de-escalation therapy appears to be urgently needed in order to improve the situation.

Ventilator-associated pneumonia in an adult clinical-surgical intensive care unit of a Brazilian university hospital: incidence, risk factors, etiology, and antibiotic resistance

The objective of this study was to evaluate clinical characteristics, etiology, and resistance to antimicrobial agents, among patients with ventilator-associated pneumonia (VAP). A case study vs. patients control under mechanical ventilation and hospitalized into clinical-surgical adults ICU of HC-UFU was performed from March/2005 to March/2006. Patients under ventilation for over 48 h were included in the study including 84 with diagnosis of VAP, and 191 without VAP (control group). Laboratory diagnosis was carried out through quantitative microbiological evaluation of tracheal aspirate. The identification of pathogens was performed by classical microbiological tests, and the antibiotics sensitivity spectrum was determined through the CLSI technique. VAP incidence rate over 1,000 days of ventilation was 24.59. The mean (± SD) duration of mechanical ventilation prior to VAP diagnosis was 23.2 ± 17.2 days. By multivariate analysis the risk factors predisposing for VAP were: mechanical ventilation time and mechanical ventilation > seven days, tracheostomy and use of > three antibiotics. Mortality rate was high (32.1 percent) but lower than that of the control group (46.5 percent). Major pathogens were identified in most of patients (95.2 percent) and included: Pseudomonas aeruginosa (29 percent), Staphylococcus aureus (26 percent), Enterobacter/Klebsiella/Serratia (19 percent) and Acinetobacter spp. (18 percent), with expressive frequencies of P. aeruginosa (52 percent), S. aureus (65.4 percent) and Enterobacteriaceae (43.7 percent) resistant to imipenem, oxacillin and 3/4 generation cephalosporins, respectively. In conclusion, our observation showed VAPs caused by multiresistant microorganisms, the prescription of > three antibiotics, and mortality with unacceptably high rates. The practice of de-escalation therapy appears to be urgently needed in order to improve the situation.

Experimental model in the qualitative and quantitative assessment of non-Helicobacter gastric microflora under proton pump inhibitors action / Modelo experimental na avaliação qualitativa e quantitativa da microflora gástrica não-Helicobacter sob ação de inibidores de bomba de próton

PURPOSE: To evaluate models of gastric material collection from Wistar rats with and without using proton pump inhibitors(PPIs). METHODS: Twenty-four rats underwent intraperitoneal omeprazol treatment, and other 12 received similar treatment with 0.9 percent saline. All animals underwent collection of gastric material samples, after stomach removal, by either biopsies, or aspirates, or swabs. Samples were bacteriologically processed in order to identify species and strains. Values are described as natural logarithm of colony former units per mL [Ln(CFU/mL)]. Kruskal-Wallis and Mann-Whitney non-parametric tests were used, and p<0.05 was set as statistically significant. RESULTS: Significant difference was not seen for Ln (UFC/mL) values among the three methods of collection irrespective of using or not omeprazol. Also, significant difference was not seen in Ln (UFC/mL) values when comparing a method with each others, either using omeprazol or placebo. A significant increase of bacteria strains occurred when PPI was used, and this was seen on the three ways of collection, mainly in biopsy and swab. CONCLUSION: No difference occurred among the three methods of collecting bacteria samples from stomachs of rats, either when using placebo or omeprazol. A remarkable change is seen on animals bacterial microflora when PPIs are used, and bacteria are better identified when swab and biopsy are used.

OBJETIVO: Avaliar modelos de coleta de material gástrico de ratos da linhagem Wistar, com e sem o uso de inibidores de bomba de próton (IBPs). MÉTODOS: 24 ratos foram submetidos a tratamento com omeprazol intraperitoneal e 12 outros ratos receberam tratamento semelhante com solução salina a 0,9 por cento. Os animais foram submetidos a coleta de amostras de material gástrico, após retirada do estômago, utilizando-se de biópsias, aspirados ou swabs. Os materiais obtidos foram processados bacteriologicamente para identificação de espécimes quanto ao gênero. Os valores são descritos em logaritmo natural das unidades formadoras de colônias por mL [Ln(UFC/mL)]. Utilizou-se os testes não-paramétricos de Kruskal-Wallis e Mann-Whitney, considerando-se p<0,05 como estatisticamente significativo. RESULTADOS: Não se observou diferença significativa da quantidade de Ln(UFC/mL) entre os três métodos de coleta, independente do uso de omeprazol. Também não se observou diferença significativa de Ln(UFC/mL) ao comparar-se os métodos individualmente entre si nas condições de uso de omeprazol ou placebo. Houve aumento significativo da variedade de gêneros de bactérias com o uso de IBP, nos 3 métodos de coleta, sendo isto mais perceptível na biópsia e swab. CONCLUSÃO: Não houve diferença entre os três métodos de coleta de amostras bacterianas de estômago de ratos, tanto em uso de placebo quanto em uso de omeprazol. Nota-se uma mudança evidente da microflora bacteriana nos animais em uso de IBPs, sendo melhor identificado pelos métodos de swab e biópsia.

Experimental model in the qualitative and quantitative assessment of non-Helicobacter gastric microflora under proton pump inhibitors action.

PURPOSE: To evaluate models of gastric material collection from Wistar rats with and without using proton pump inhibitors(PPIs). METHODS: Twenty-four rats underwent intraperitoneal omeprazol treatment, and other 12 received similar treatment with 0.9% saline. All animals underwent collection of gastric material samples, after stomach removal, by either biopsies, or aspirates, or swabs. Samples were bacteriologically processed in order to identify species and strains. Values are described as natural logarithm of colony former units per mL [Ln(CFU/mL)]. Kruskal-Wallis and Mann-Whitney non-parametric tests were used, and p<0.05 was set as statistically significant. RESULTS: Significant difference was not seen for Ln (UFC/mL) values among the three methods of collection irrespective of using or not omeprazol. Also, significant difference was not seen in Ln (UFC/mL) values when comparing a method with each others, either using omeprazol or placebo. A significant increase of bacteria strains occurred when PPI was used, and this was seen on the three ways of collection, mainly in biopsy and swab. CONCLUSION: No difference occurred among the three methods of collecting bacteria samples from stomachs of rats, either when using placebo or omeprazol. A remarkable change is seen on animals bacterial microflora when PPIs are used, and bacteria are better identified when swab and biopsy are used.

Infection and colonization by Gram-negative bacilli in neonates hospitalized in High Risk Nursery at Uberlandia Federal University Hospital: etiology, resistant phenotypes and risk factors

Os objetivos deste estudo foram determinar infecções endêmicas e epidêmicas por bacilos Gram-negativos, fatores de risco associados a colonização e infecção e a presença dos fenótipos de resistência ESBL e AmpC em neonatos admitidos em Berçário de Alto Risco. Durante um período de 21 meses, foi realizado um estudo prospectivo para avaliar os casos de infecções hospitalares e o uso de cefalosporinas de terceira geração; e um estudo caso-controle para determinar os fatores de risco associados a colonização/infecção. Quatro inquéritos de colonização da orofaringe e intestino dos neonatos (Setembro e Novembro/2001, Fevereiro e Agosto/2002). Amostras com resistência a 2 mg/mL de ceftazidima foram isoladas devido a suspeita de produção de b-lactamases (ESBL/ AmpC). A incidência de pacientes infectados por bacilos Gram-negativos foi de 2,4% (89/3.709 neonatos), sendo sepse (35,9%) e conjuntivite (31,4%) as síndromes mais frequentes. A maioria das infecções foram endêmicas (73,9%) e associadas a Enterobacteriaceae (95,5%), estes também foram relacionados à colonização, correspondendo principalmente as amostras de Enterobacter spp e Klebsiella spp.. Foram identificados dois surtos, durante o estudo, associados a Pseudomonas aeruginosa (N=10) e Acinetobacter baumannii (N=11). Os fatores de risco incluindo: tempo de internação, uso de antimicrobianos, ventilação mecânica, cateter vascular central, cirurgia e nutrição parenteral foram significativos em uma análise univariada e considerados um risco para infecção por bacilos Gram-negativos. A maioria das amostras de Enterobacteriaceae (80,9%) com resistência a 2 mg/mL de ceftazidima foram do fenótipo ESBL. O uso de cefalosporinas de terceira geração (ceftriaxona) na unidade neonatal favoreceu a emergência de bacilos Gram-negativos multiresistentes.