Incidence of urinary tract infection after cystography / Incidência de infecção urinária após cistografia

ABSTRACT Objective: Cystography an invasive procedure with potential complications such as urinary infection (UI). There are few studies about the incidence of complications associated with this procedure. The purpose of this study is to evaluate the incidence of post-cystography urinary infection (UI.). Methods: Retrospective study with a review of clinical records of patients under 15 years of age, followed in this hospital, who underwent cystography (radiologic or indirect radionuclide) between 2009 and 2018. Post-cystography UI was defined when it occurred until seven days after the procedure. Descriptive and nonparametric statistics were applied to assess possible predictive factors related with post-cystography UI. Results: In the study period, 531 cystograms were undertaken (55% indirect radionuclide and 45% radiologic). The mean age at the procedure was 11.5 months; 62% were boys. Every patient had a previous negative urine culture; 50% were under antibiotic prophylaxis at the time of the procedure. The most common indication for the procedure was the post-natal study of congenital hydronephrosis/other nephrological malformation (53%), followed by the study of febrile UI (31%). Vesicoureteral reflux (VUR) was diagnosed in 40% of procedures. Post-cystography UI occurred in 23 cases (incidence of 4.3%). The most frequent microorganism was E. coli (52%). The presence of VUR was significantly associated with the occurrence of post-cystography IU. Conclusions: The incidence of post-cystography UI was low in our sample. The presence of VUR was significantly associated with the occurrence of post-cystography UI. The authors highlight the importance of an adequate catheterization technique and the need for clinical surveillance after the procedure.

RESUMO Objetivo: A cistografia é um exame invasivo que apresenta potencial iatrogenia, nomeadamente infecção urinária (IU). Os estudos sobre a incidência de complicações associadas a esse exame são escassos. O objetivo deste trabalho foi avaliar a incidência de IU após realização de cistografia. Métodos: Estudo retrospetivo por consulta dos prontuários clínicos dos doentes com idade inferior a 15 anos, seguidos em consulta nesse hospital, que realizaram cistografia (radiológica ou isotópica) entre 2009 e 2018. Admitiu-se relação de causalidade quando o diagnóstico de IU ocorreu até sete dias após a realização do exame. Foi realizada análise estatística descritiva e utilizados testes não paramétricos para avaliar possíveis fatores preditores da ocorrência de IU após cistografia. Resultados: Realizaram-se 531 cistografias (55% isotópicas e 45% radiológicas). A mediana de idade foi de 11,5 meses; 62% eram do sexo masculino. Todos os doentes efetuaram urocultura prévia (negativa); 50% recebiam profilaxia antibiótica (ATB) à data do exame. A indicação mais frequente foi o estudo pós-natal de hidronefrose (HN) congênita/outra malformação nefrourológica (53%), seguida do estudo da IU febril (31%). Documentou-se refluxo vesicoureteral (RVU) em 40% dos exames. Ocorreu IU após cistografia em 23 casos (incidência de 4,3%). O microrganismo mais frequente foi a E. coli (52%). Verificou-se associação entre a presença de RVU e a ocorrência de IU. Conclusões: A incidência de IU pós-cistografia foi relativamente baixa na amostra deste estudo. Observou-se associação entre a ocorrência de IU após cistografia e a presença de RVU. Sublinha-se a importância de uma técnica adequada de cateterização vesical e da vigilância clínica após o exame.

INCIDENCE OF URINARY TRACT INFECTION AFTER CYSTOGRAPHY.

OBJECTIVE: Cystography an invasive procedure with potential complications such as urinary infection (UI). There are few studies about the incidence of complications associated with this procedure. The purpose of this study is to evaluate the incidence of post-cystography urinary infection (UI.). METHODS: Retrospective study with a review of clinical records of patients under 15 years of age, followed in this hospital, who underwent cystography (radiologic or indirect radionuclide) between 2009 and 2018. Post-cystography UI was defined when it occurred until seven days after the procedure. Descriptive and nonparametric statistics were applied to assess possible predictive factors related with post-cystography UI. RESULTS: In the study period, 531 cystograms were undertaken (55% indirect radionuclide and 45% radiologic). The mean age at the procedure was 11.5 months; 62% were boys. Every patient had a previous negative urine culture; 50% were under antibiotic prophylaxis at the time of the procedure. The most common indication for the procedure was the post-natal study of congenital hydronephrosis/other nephrological malformation (53%), followed by the study of febrile UI (31%). Vesicoureteral reflux (VUR) was diagnosed in 40% of procedures. Post-cystography UI occurred in 23 cases (incidence of 4.3%). The most frequent microorganism was E. coli (52%). The presence of VUR was significantly associated with the occurrence of post-cystography IU. CONCLUSIONS: The incidence of post-cystography UI was low in our sample. The presence of VUR was significantly associated with the occurrence of post-cystography UI. The authors highlight the importance of an adequate catheterization technique and the need for clinical surveillance after the procedure.

Risk of infection in patients undergoing urologic surgery based on the presence of asymptomatic bacteriuria: A prospective study.

BACKGROUND: Treatment of asymptomatic bacteriuria (ASB) is recommended in pregnant women and prior to urologic procedures with anticipated mucosal disruption. However, there is still insufficient evidence of the usefulness of treating ASB prior to urologic procedures. Therefore, the aim of this study was to ascertain the risk of infections in patients undergoing urologic surgery based on the presence of ASB. METHODS: We conducted a cohort study among patients undergoing urologic surgery at a single center located in Medellín, Colombia. All patients were screened for ASB prior to their procedures. Patients were evaluated for the development of any postoperative infectious complications for up to 30 days after the procedure. RESULTS: A total of 149 patients were included in this cohort. Incidence of ASB was 14.8%. Thirteen patients (8.72%) developed infectious complications: 3 (13.64%) with ASB and 10 (7.87%) without ABS. Factors associated with postoperative infectious complications included urologic cancers (hazard ratio [HR], 5.26; 95% confidence intervals [CI], 1.24-22.37), urologic interventions in the preceding 3 months (HR, 3.72; 95% CI, 1.02-13.51), and use of antibiotics 3 months prior to surgery (HR, 3.83; 95% CI, 1.01-15.49). Presence of ASB was not associated with postsurgical infectious complications (HR, 1.02; 95% CI, 0.26-3.96). CONCLUSIONS: There was no association between ASB and postoperative infectious complications. There were other factors associated with infectious complications, such as urologic cancer, previous history of urologic manipulation, and antibiotic use.

Absorbable Antibiotic Beads Prophylaxis in Immediate Breast Reconstruction.

BACKGROUND: Breast reconstruction with tissue expanders is the most common mode of reconstruction following mastectomy. Infection necessitating tissue expander removal is a significant complication leading to patient distress and increased health care costs. METHODS: Over 3 years, 127 breast reconstructions with tissue expanders were performed by a single surgeon. Fifty-nine of these reconstructions were performed using a standardized protocol in which patients washed with chlorhexidine several days before surgery and received intravenous antibiotics preoperatively. Intraoperatively, the submuscular pocket was irrigated with triple-antibiotic solution and the skin was prepared again with povidone-iodine before expander placement. This group was referred to as the preintervention group. Sixty-eight of the reconstructions were performed using the standardized protocol with the addition of biodegradable antibiotic beads (Stimulan with vancomycin and gentamicin) in the submuscular pocket. This group made up the postintervention group. The primary outcome was the rate of infection necessitating tissue expander removal. RESULTS: The rate of tissue expander loss caused by infection was 11.9 percent in the preintervention group and 1.5 percent in the postintervention group (p = 0.024). Higher body mass index was associated with a statistically significant increase in infections necessitating expander removal. CONCLUSION: The use of absorbable antibiotic beads in the submuscular pocket reduced the risk of periprosthetic implant infection necessitating implant removal by 8-fold. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Fecal ESBL Escherichia coli carriage as a risk factor for bacteremia in patients with hematological malignancies.

PURPOSE: The purpose of this study is to evaluate the impact of fecal extended-spectrum ß-lactamase-producing Escherichia coli (ESBL-EC) colonization for bloodstream infection (BSI), clinical outcome, and costs in patients with hematologic malignancies (HM) and severe neutropenia. METHODS: This is a cohort study, carried out at a cancer-referral hospital. The study population comprises patients with HM, hospitalized prior to administration of the first chemotherapy cycle. A stool culture was taken during the first 48 h; they were grouped as colonized by ESBL-EC or non-ESBL-EC. Patients were followed upon completion of chemotherapy or death. The sum of the days of antibiotics and the length of stay of all hospitalizations in the different cycles of chemotherapy were recorded. RESULTS: We included 126 patients with a recent diagnosis of HM, grouped as 63 patients colonized by ESBL-EC and 63 colonized by non-ESBL-EC, aged 42 ± 16 years old, 78 males (62%). BSI by ESBL-EC developed in 14 patients (22.2%) colonized by the same strain and in 5 (7.9%) in the group colonized with non-ESBL-EC. BSI by non-ESBL-EC was observed in 3 patients (4.7%) colonized by ESBL-EC and in 17 (26.9%) patients colonized by non-ESBL-EC. Colonization with ESBL-EC increased the risk of BSI by the same strain (relative risk (RR) = 3.4, 95% confidence interval (95% CI) 1.5-7.8, p = 0.001), shorter time to death (74 ± 62 vs. 95 ± 83 days, p < 0.001), longer hospital stay (64 ± 39 vs. 48 ± 32 days, p = 0.01), and higher infection-related costs ($6528 ± $4348 vs. $4722 ± $3173, p = 0.01). There was no difference in overall mortality between both groups. CONCLUSIONS: Fecal colonization by ESBL-EC is associated with increased risk of BSI by this strain, longer hospital stay, and higher related costs.

[Autologous mesenchymal stem cells and cutaneus autograft as a treatment for chronic ulcer secondary to diabetes mellitus 2]. / Células troncales mesenquimales autólogas e injerto cutáneo autólogo para tratamiento de una úlcera crónica secundaria a diabetes mellitus tipo2.

BACKGROUND: Diabetes mellitus 2 has become a global problem. It is estimated that 15% to 25% of patients could develop a chronic ulcer in their life, and nearly 33% of direct care costs of the diabetes mellitus 2 is spent on treating these ulcers. Mesenchymal stem cells have emerged as a promising cell source for the treatment of these ulcers. CLINICAL CASE: The case is presented of a 67 year-old male with a history of diabetes mellitus, acute myocardial infarction, and food ulcer chronic involving right foot and part of his leg. He was treated with mesenchymal stem cell management, resulting in skin graft integration and full coverage of the lesion. CONCLUSION: The implementation of mesenchymal stem cell techniques for treatment of chronic ulcer is feasible. The impact on the population would lead to a significant improvement in their quality of life and reduce healthcare spending.

[Fecal microbiota transplantation: first case report in Chile and review]. / Trasplante de microbiota fecal: primer caso reportado en Chile y revisión de la literatura.

Clostridium difficile (CD) infection is increasing in frequency and severity in in-hospital and outpatient clinical settings, with a recurrence that can reach 30% after first episode. The recurrences are usually treated with longer courses of metronidazole or vancomycin. Other treatments have been used, such as probiotics, fidaxomicin, rifaximin, immunoglobulins and monoclonal antibodies against toxins A and B. Fecal microbiota transplantation (FMT) has emerged as a promising strategy in this group of patients, with effectiveness greater than 90%. We present the first case reported in Chile of this therapeutic strategy in a patient with Crohn's disease and recurrent CD infection who presented after the fecal transplantation an Escherichia coli bacteremia, suggesting the need for caution in the use of this strategy. 10 months after the FMT the patient presented a new episode of E. coli bacteremia and two episodes of diarrhea due to CD infection, treated both of them with vancomycin with good clinical response.

Urinary tract infection in renal transplant recipients: incidence, risk factors, and impact on graft function.

INTRODUCTION: Urinary tract infection (UTI) is the most common infection posttransplant. However, the risk factors for and the impact of UTIs remain controversial. The aim of this study was to identify the incidence of posttransplant UTIs in a series of renal transplant recipients from deceased donors. Secondary objectives were to identify: (1) the most frequent infectious agents; (2) risk factors related to donor; (3) risk factors related to recipients; and (4) impact of UTI on graft function. PATIENTS AND METHODS: This was a retrospective analysis of medical records from renal transplant patients from January to December 2010. Local ethics committee approved the protocol. RESULTS: The incidence of UTI in this series was 34.2%. Risk factors for UTI were older age, (independent of gender), biopsy-proven acute rejection episodes, and kidneys from deceased donors (United Network for Organ Sharing criteria). For female patients, the number of pretransplant pregnancies was an additional risk factor. Recurrent UTI was observed in 44% of patients from the UTI group. The most common infectious agents were Escherichia coli and Klebsiella pneumoniae, for both isolated and recurrent UTI. No difference in renal graft function or immunosuppressive therapy was observed between groups after the 1-year follow-up. CONCLUSIONS: In this series, older age, previous pregnancy, kidneys from expanded criteria donors, and biopsy-proven acute rejection episodes were risk factors for posttransplant UTI. Recurrence of UTI was observed in 44%, with no negative impact on graft function or survival.

Trasplante de microbiota fecal: primer caso reportado en Chile y revisión de la literatura / Fecal microbiota transplantation: first case report in Chile and review

Clostridium difficile (CD) infection is increasing in frequency and severity in in-hospital and outpatient clinical settings, with a recurrence that can reach 30% after first episode. The recurrences are usually treated with longer courses of metronidazole or vancomycin. Other treatments have been used, such as probiotics, fidaxomicin, rifaximin, immunoglobulins and monoclonal antibodies against toxins A and B. Fecal microbiota transplantation (FMT) has emerged as a promising strategy in this group of patients, with effectiveness greater than 90%. We present the first case reported in Chile of this therapeutic strategy in a patient with Crohn's disease and recurrent CD infection who presented after the fecal transplantation an Escherichia coli bacteremia, suggesting the need for caution in the use of this strategy. 10 months after the FMT the patient presented a new episode of E. coli bacteremia and two episodes of diarrhea due to CD infection, treated both of them with vancomycin with good clinical response.

La infección por Clostridium difficile (CD) está aumentando en frecuencia y gravedad tanto a nivel intrahospitalario como ambulatorio, con una recurrencia que puede alcanzar hasta 30% después de un primer episodio. Los cuadros recurrentes son generalmente tratados con cursos prolongados de metronidazol y/o vancomicina. Otras terapias han sido sugeridas como el uso de probióticos, fidaxomicina, rifaximina, inmunoglobulina y anticuerpos monoclonales para toxina A y B. El trasplante de microbiota fecal (TMF) ha emergido como una estrategia promisoria en este grupo de pacientes con una efectividad mayor a 90%. Presentamos el primer caso reportado en Chile de esta estrategia terapéutica en un paciente con enfermedad de Crohn y CD recurrente, quien presentó una bacteriemia por Escherichia coli post-TMF, sugiriendo la necesidad de tener precaución con el uso de esta estrategia. El paciente presentó a los 10 meses post-TMF un nuevo episodio de bacteriemia por E. coli y dos episodios de diarrea por CD siendo tratados ambos cuadros con vancomicina con buena respuesta clínica.

Aetiology of bacteraemia as a risk factor for septic shock at the onset of febrile neutropaenia in adult cancer patients.

Septic shock (SS) at the onset of febrile neutropaenia (FN) is an emergency situation that is associated with high morbidity and mortality. The impact of the specific aetiology of bloodstream infections (BSIs) in the development of SS at the time of FN is not well established. The aim of this study was to evaluate the association between the aetiology of BSIs and SS at the time of FN in hospitalised adult cancer patients. This prospective cohort study was performed at a single tertiary hospital from October 2009 to August 2011. All adult cancer patients admitted consecutively to the haematology ward with FN were evaluated. A stepwise logistic regression was conducted to verify the association between the microbiological characteristics of BSIs and SS at the onset of FN. In total, 307 cases of FN in adult cancer patients were evaluated. There were 115 cases with documented BSI. A multivariate analysis showed that polymicrobial bacteraemia (P = 0.01) was associated with SS. The specific blood isolates independently associated with SS were viridans streptococci (P = 0.02) and Escherichia coli (P = 0.01). Neutropaenic cancer patients with polymicrobial bacteraemia or BSI by viridans streptococci or Escherichia coli are at increased risk for SS at the time of FN.

Relevance of biofilms in the pathogenesis of Shiga-toxin-producing Escherichia coli infection.

The present study was designed to determine the relationships among biofilm formation, cellular stress and release of Shiga toxin (Stx) by three different clinical Shiga toxin-producing Escherichia coli (STEC) strains. The biofilm formation was determined using crystal violet stain in tryptic soy broth or thioglycollate medium with the addition of sugars (glucose or mannose) or hydrogen peroxide. The reactive oxygen species (ROSs) were detected by the reduction of nitro blue tetrazolium and reactive nitrogen intermediates (RNI) determined by the Griess assay. In addition, the activities of two antioxidant enzymes, superoxide dismutase (SOD) and catalase (CAT), were studied. For the cytotoxicity studies, Vero cells were cultured with Stx released of STEC biofilms. The addition of sugars in both culture mediums resulted in an increase in biofilm biomass, with a decrease in ROS and RNI production, low levels of SOD and CAT activity, and minimal cytotoxic effects. However, under stressful conditions, an important increase in the antioxidant enzyme activity and high level of Stx production were observed. The disturbance in the prooxidant-antioxidant balance and its effect on the production and release of Stx evaluated under different conditions of biofilm formation may contribute to a better understanding of the relevance of biofilms in the pathogenesis of STEC infection.

Global causes of diarrheal disease mortality in children <5 years of age: a systematic review.

Estimation of pathogen-specific causes of child diarrhea deaths is needed to guide vaccine development and other prevention strategies. We did a systematic review of articles published between 1990 and 2011 reporting at least one of 13 pathogens in children <5 years of age hospitalized with diarrhea. We included 2011 rotavirus data from the Rotavirus Surveillance Network coordinated by WHO. We excluded studies conducted during diarrhea outbreaks that did not discriminate between inpatient and outpatient cases, reporting nosocomial infections, those conducted in special populations, not done with adequate methods, and rotavirus studies in countries where the rotavirus vaccine was used. Age-adjusted median proportions for each pathogen were calculated and applied to 712 000 deaths due to diarrhea in children under 5 years for 2011, assuming that those observed among children hospitalized for diarrhea represent those causing child diarrhea deaths. 163 articles and WHO studies done in 31 countries were selected representing 286 inpatient studies. Studies seeking only one pathogen found higher proportions for some pathogens than studies seeking multiple pathogens (e.g. 39% rotavirus in 180 single-pathogen studies vs. 20% in 24 studies with 5-13 pathogens, p<0.0001). The percentage of episodes for which no pathogen could be identified was estimated to be 34%; the total of all age-adjusted percentages for pathogens and no-pathogen cases was 138%. Adjusting all proportions, including unknowns, to add to 100%, we estimated that rotavirus caused 197 000 [Uncertainty range (UR) 110 000-295 000], enteropathogenic E. coli 79 000 (UR 31 000-146 000), calicivirus 71 000 (UR 39 000-113 000), and enterotoxigenic E. coli 42 000 (UR 20 000-76 000) deaths. Rotavirus, calicivirus, enteropathogenic and enterotoxigenic E. coli cause more than half of all diarrheal deaths in children <5 years in the world.

Anomalías del tracto urinario y microorganismos diferentes a Escherichia coli en la infección urinaria neonatal / Anomalies of the urinary tract and microorganism other than Escherichia coli in the neonatal urinary infection

Objetivo: verificar si existe asociación entre tipo de microorganismo aislado en recién nacidos que inician una infección del tracto urinario y la presencia de anomalías del tracto urinario. Métodos: estudio observacional, prospectivo, desde 1992 hasta 2010, de una cohorte de 427 recién nacidos que ingresaron con la primera infección del tracto urinario, de localización alta, por criterios clínicos, y que se realizaron ultrasonido renal y uretrocistografía miccional. Se analizó la asociación entre la presencia de reflujo vésico-ureteral y otras anomalías del tracto urinario, con el tipo de microorganismo causal de la infección del tracto urinario. Resultados: los aislamientos bacterianos en los urocultivos correspondieron en 402 de los pacientes a microorganismos del género Enterobacteriaceae (94,1 por ciento), liderados por la E. coli en 276 (64,6 por ciento). La prevalencia de anomalías del tracto urinario resultó ser de 23,6 x 100. El problema más prevalente fue el reflujo vésico-ureteral, presente en 82 pacientes (19,2 x 100). Se comprobó que la presencia de reflujo vésico-ureteral tuvo asociación de riesgo estadísticamente significativa con el microorganismo causal diferente a E. coli (RR: 1,56; p< 0,05). De igual manera, se relacionó la presencia de reflujo vésico-ureteral o de otro tipo de anomalía del tracto urinario, con el microorganismo causal de la infección del tracto urinario, y los resultados del análisis fueron similares (RR:1,64; p< 0,01). Conclusiones: aunque la E. coli es el microorganismo causal más frecuente de la infección del tracto urinario neonatal, cuando se obtiene un aislamiento diferente a E. coli es muy probable que el paciente sea portador de una anomalía del tracto urinario, dado que la presencia de reflujo vésico-ureteral y otras anomalías del tracto urinario se asocian significativamente a aquellos diferentes a E. coli

Objective: to confirm whether the type of microorganism isolated in newborns with initial urinary tract infection and the anomalies of the urinary tract are associated or not. Methods: prospective and observational study of a cohort of 427 newborns, who were admitted to the hospital with their first urinary infection in the upper tract based on clinical criteria, and they underwent renal ultrasound and urethrocystography. The relationship between the vesicourethral reflux and other anomalies of the urinary tract with the type of causative microorganism of the urinary tract infection was analyzed. Results: bacterial isolates in uricultures were Enterobacteriaceae genus microorganisms in 402 patients (94.1 percent), led by E. coli in 276 (64.6 percent ). The prevalence of anomalies of the urinary tract was 23.6 x 100. The most prevalent problem was vesicourethral reflux found in 82 patients (19.2 x 100). It was confirmed that the presence of vesicourethral reflux had statistically significant association, in terms of risk, with causative microorganism other than E.coli (RR: 1.56; p< 0.05). Similarly, the presence of vesicourethral reflux or of other type of anomalies in the urinary tract was related to the causative microorganism of the urinary tract infection and the results of the analysis were similar (RR:1.64; p< 0.01). Conclusions: although E.coli is the most frequent causative microorganism of the neonatal urinary tract infection, when an isolate different from E. coli is obtained, it is very likely that the patient carries some anomaly of the urinary tract since the presence of the vesicourethral reflux and other anomalies of the urinary tract are significantly associated to microorganisms other than E.coli

[Sigmoido-buttock fistula by diverticulitis: report of a rare complication]. / Fístula sigmoideo-glútea por diverticulitis. Reporte de una rara complicación.

INTRODUCTION: The complicated diverticulitis of the colon is characterized by its association with abscesses, bleeding, stenosis, perforation, obstruction or fistula. We report a case of spontaneous sigmoido-cutaneous fistula from diverticulitis to an unusual place in the gluteal region. CLINICAL CASE: A 59-year-old male patient presented an inflammatory wound in left buttock without response to the conservative medical treatment. The fistulography, colonoscopy, barium enema and computed tomography showed a sigmoido-cutaneous fistula to the left buttock from diverticulitis. The biopsy of the lesion ruled out malignancy. We performed an elective sigmoid resection with primary colorectal anastomosis, partial fistulectomy and injection of a fibrin sealant in the residual tract. DISCUSSION: The colon-cutaneous fistulas from diverticulitis are relatively rare. We report a spontaneous fistula with origin in a single diverticulum in the sigmoid colon and that drained through the piriform fossa of the pelvic floor to the skin of the left buttock. CONCLUSIONS: A high index of suspiscion is necessary to not confuse the colo-buttock fistula with local abscesses.

Antibióticos y expresión de betalactamasas de espectro extendido (BLEE) en agentes bacterémicos / Use of antibiotics and expression of extended spectrum betalactamases (ESBL) in bacteremic agents

Objective: To evaluate the association between Escherischia Coli (E. Coli) and Klebsiella spp bacteremia, both of which produce Extended Spectrum beta-lactamases (ESBL), and the use of third generation cephalos-porines (TGC) during 30 days prior to the development of the infection. Patients and Methods: Case study of all patients hospitalized between 2004 and 2007 at Hospital de Niños Roberto del Río, who presented E. coli y Klebsiella spp bacteremia. Results: 212 episodes of E. coli o Klebsiella spp bacteremias were found; 205 contained all necessary data, 47 of which were cases and 158 were controls. The use of TGC showed a statistically significant correlation with the finding of ESBL in those patients' bacteremias (OR 2,5; IC95 percent 1,26-5). In addition, an independent statistically significant association was found with hospital acquired infections (OR 8,2; IC95 percent 2,7-27,1), and the use of Central Venous Catheter (OR 38,9; IC95 percent 14,3-106,0) became close to statistical significance. Conclusions: This study shows a statistically significant association between ESBL bacteremias and use of TGC within 30 days prior to the infection, confirming other literature reports.

Objetivo: Estudiar la asociación entre bacteriemia por E. coli y Klebsiella spp productoras de beta-lactamasas de espectro extendido (BLEE) y el uso de cefalosporinas de tercera generación (CTG) durante los 30 días previos al desarrollo de la infección. Método: Estudio caso control encestado desarrollado entre los años 2004 y 2007 en el Hospital de Niños Roberto del Río, con análisis retrospectivo de los pacientes con bacteriemias por E. coli y Klebsiella spp. Resultados: Se registraron 212 episodios de bacteriemias por E. coli o Klebsiella spp, en 205 de ellos se contó con los registros necesarios, 47 fueron casos y 158 controles. El uso de CTG se asoció de modo estadísticamente significativo con la probabilidad de aislar cepas BLEE de bacteriemias en estos pacientes (OR 2,5; IC95 por ciento 1,26-5). Además, se observó asociación independiente y estadísticamente significativa con Infección Intrahospitalaria (OR 8,2; IC95 por ciento 2,7-27,1), y el uso de Catéter Venoso Central (OR 38,9; IC95 por ciento 14,3-106,0) se acercó a la significancia estadística. Conclusiones: Nuestro trabajo establece la asociación estadística entre bacteriemia por cepas BLEE y el uso de CTG dentro de los 30 días previos al desarrollo de la infección, confirmando lo sugerido por la literatura.

Putative new heat-stable cytotoxic and enterotoxic factors in culture supernatant of Escherichia coli isolated from drinking water

Enteric infections caused by the ingestion of contaminated water, especially by Escherichia coli, are important to define the virulence properties of these bacteria. Due to frequent infantile diarrhea in the city of Ouro Preto, Minas Gerais state, Brazil, the phenotypic and genotypic diarrheagenic properties of E. coli isolated from drinking water were studied. The culture supernatants of 39 (40 percent) among a total of 97 E. coli isolates from drinking water were positive by suckling mouse assay and induced cytotoxic effects on Vero cells. The enterotoxic and cytotoxic activities were present in the fraction with less than 10 kDa and were not lost when heated up to 60ºC and 100ºC for 30 minutes. PCR assays showed that among these 39 Vero cytotoxigenic E. coli, four (10.2 percent) were positive for ST II (estB) and two (5 percent) positive for αHly (hlyA). Gene amplification of SLT (stx 1, stx 2), ST I (estA), LT (eltI, eltII), EAST1 (astA), EHly (enhly) and plasmid-encoded enterotoxin (pet) were not observed. This heat-stable cytotoxic enterotoxin of E. coli is probably a new putative diarrheagenic virulence factor, as a toxin presenting these characteristics has not yet been described.(AU)

Diarrheagenic Escherichia coli in human immunodeficiency virus (HIV) pediatric patients in Lima, Peru.

We conducted a prospective study in three hospitals in Lima in human immunodeficiency virus (HIV) children to determine the frequency of diarrheagenic Escherichia coli. Five E. coli colonies/patients were studied by a multiplex real-time polymerase chain reaction to identify the six currently recognized groups of diarrhea-associated E. coli. We have analyzed 70 HIV-associated diarrheal and 70 control samples from HIV-infected children without diarrhea. Among the diarrheal episodes 19% were persistent, 3% dysenteric, and 33% were associated with moderate or severe dehydration. The diarrheagenic E. coli were the most commonly isolated pathogens in diarrhea (19%) and control samples (26%) (P = 0.42), including enteroaggregative (6% versus 10%), enteropathogenic (6% versus 10%), and enterotoxigenic E. coli (4% versus 3%), respectively. The HIV-infected children with diarrhea had the worse age-related immunosuppression, higher viral loads, and were on highly active antiretroviral treatment (HAART) less often than HIV-infected children without diarrhea. Diarrheagenic E. coli were highly resistant to ampicillin (74%) and cotrimoxazole (70%).

Etiología bacteriana de la diarrea aguda en pacientes pediátricos / Bacterial etiology of acute diarrhea in pediatric patients

La diarrea aguda es una causa importante de morbilidad y mortalidad en países en desarrollo. Sólo requiere tratamiento antimicrobiano en situaciones puntuales y el uso adecuado de los mismos depende del conocimiento previo de la epidemiología local. Para conocer estos parámetros se estudiaron en forma retrospectiva los resultados bacteriológicos de 7.075 muestras de materia fecal de niños ambulatorios hasta 15 años, en el período 2001-2003, atendidos en el Hospital de Niños de La Plata. Se aislaron 1.221 bacterias enteropatógenas (17,26%). Los patógenos identificados por métodos estándar fueron: Shigella flexneri(27%), Shigella sonnei(21,2%), Campylobacterspp. (30,1%), Aeromonas spp.(9,4%), Salmonella spp. (5,4%), Escheríchia coli enteropatógena (5,7%), Escheríchia coli enteroinvasiva (0,9%) y Escheríchia coliO157 (0,4%). No se aislaron cepas de Shigella dysenteriae, Shigella boydii ni Yersinia spp. Las cepas de Shigella flexneri presentaron una alta resistencia: ampicilina (92,4%, 89,2% y 91,9%), cotrimoxazol (51,5%, 50% y 44,4%) y cloranfenicol (73,8%, 85,9% y 79,2%) en 2001, 2002 y 2003, respectivamente. En el caso de Shigella sonnei, la resistencia a ampicilina fue menor (39,4%, 20,6% y 12,9%), la resistencia a cotrimoxazol fue similar (60,6%, 54,3% y 38,7%) y para cloranfenicol mucho menor aún (6%, 2,9% y 3,3%) en los mismos años. No se aislaron cepas resistentes a ciprofloxacina, nitrofuranos ni cefalosporinas de tercera generación en el período de estudio.

Acute diarrhea is an important cause of morbidity and mortality in developing countries, and in some cases, it requires antimicrobial therapy .The use of antibiotics needs a previous knowledge of local epidemiology. In order to know these parameters, the result of enteropathogenic bacteria isolated from 7.075 fecal samples from ambulatory patients up to 15 years old, assisted at the Hospital de Niños de La Plata from 2001 to 2003 was retrospectively studied. A total of 1,221 enteropathogenic bacteria were isolated (17.26%). The pathogens identified by standard methods were Shigella flexneri (27%), Shigella sonnei (21.2%), Campylobacter spp.(30.1%), Aeromonas spp.(9.4%), Salmonella spp. (5.4%), enteropathogenic Escherichia coli ( 5.7% ), enteroinvasive Escherichia coli (0.9%) and Escherichia coli 0157 (0.4%). Strains from Shigella dysenteriae, Shigella boydii and Yersinia spp were not isolated in this study. Shigella flexneri strains were resistant to ampicillin (92.4%, 89.2%, 91.9%), cotrimoxazole (51.5%, 50%, 44%) and chloramphenicol (73.8%, 85.9%, 79.2%) for 2001, 2002 and 2003 respectively. Shigella sonnei strains were resistant to ampicillin (39.4%, 20.6%,12.9%), cotrimoxazole (60.6%, 54.3% 38.7%) and chloramphenicol (6%, 2.9%, 3.3%) for each year. Strains resistant to ciprofloxacin, nitrofurans and third generation cephalosporins were not isolated.

[Hamburger consumption patterns and exposure assessment for verocytotoxigenic Escherichia coli (VTEC): simulation model]. / Hábitos de consumo de hamburguesas y riesgo de exposición a Escherichia coli verotoxigénica (VTEC): modelo de simulación.

A quantitative risk assessment was developed for verocytotoxigenic Escherichia coli (VTEC) associated with hamburger consumption. The assessment (simulation model) considers the distribution, storage and consumption patterns of hamburgers. The prevalence and concentration of VTEC were modelled at various stages along the agri-food beef production system using input derived from Argentinean data, whenever possible. The model predicted an infection risk of 4.45 x 10(-4) per meal for adults. The risk values obtained for children were 2.6 x 10(-4), 1.38 x 10(-5) and 4.54 x 10(-7) for infection, Hemolytic Uremic Syndrome (HUS) and mortality, respectively. The risk of infection and HUS was positively correlated with bacterial concentration in meat (r = 0.664). There was a negative association between homemade hamburgers (r = -0.116) and the risk of illness; however this association has been considered due to differences between retail and domiciliary storage systems (r = -0.567) and not because of the intrinsic characteristics of the product. The most sensitive points of the production system were identified through the risk assessment, therefore, these can be utilized as a basis to apply different risk management policies in public health.

Hábitos de consumo de hamburguesas y riesgo de exposición a Escherichia coli verotoxigénica (VTEC): modelo de simulación / Hamburger consumption patterns and exposure assessment for verocytotoxigenic Escherichia coli (VTEC): simulation model

El objetivo del trabajo fue evaluar cuantitativamente el riesgo para la salud pública debido a la infección por VTEC derivado del consumo de hamburguesas. Mediante un modelo de simulación, se analizaron procesos de distribución, almacenamiento y venta, así como hábitos de consumo. La prevalencia y concentración de VTEC fue incluida en el modelo sobre la base de información científica publicada acerca de la enfermedad. Las distribuciones de probabilidad que mejor describieron cada paso del proceso fueron incorporadas en el programa @RiskR, y se realizaron múltiples simulaciones empleando el análisis Monte Carlo. El riesgo estimado de padecer la infección por VTEC en los adultos fue de 4,45 x 10-4; mientras que en los niños, los riesgos de adquirir la infección, de padecer Síndrome Urémico Hemolítico (SUH) y de mortalidad fueron de 2,6 x 10-4, 1,38 x 10-5 y 4,54 x 10-7, respectivamente. El riesgo de adquirir la infección y sus secuelas estuvo correlacionado con la concentración bacteriana en la carne (r = 0,664). El consumo de hamburguesas de elaboración propia (r = -0,203) estuvo asociado con el riesgo de enfermar dadas las características del almacenamiento (r = -0,567), que forman parte de los hábitos de consumo de la población. La información generada debería considerarse durante el diseño de estrategias de gestión y comunicación del riesgo del SUH, con énfasis en la importancia que estos factores tienen en la trasmisión de la enfermedad.

A quantitative risk assessment was developed for verocytotoxigenic Escherichia coli (VTEC) associated with hamburger consumption. The assessment (simulation model) considers the distribution, storage and consumption patterns of hamburgers. The prevalence and concentration of VTEC were modelled at various stages along the agri-food beef production system using input derived from Argentinean data, whenever possible. The model predicted an infection risk of 4.45 x 10-4 per meal for adults. The risk values obtained for children were 2.6 x 10-4, 1.38 x 10-5 and 4.54 x10-7 for infection, Hemolytic Uremic Syndrome (HUS) and mortality, respectively. The risk of infection and HUS was positively correlated with bacterial concentration in meat (r = 0.664). There was a negative association between homemade hamburgers (r = -0.116) and the risk of illness; however this association has been considered due to differences between retail and domiciliary storage systems (r = -0.567) and not because of the intrinsic characteristics of the product. The most sensitive points of the production system were identified through the risk assessment, therefore, these can be utilized as a basis to apply different risk management policies in public health.