[Clinical significance of Staphylococcus aureus in urine]. / Significado clínico del aislamiento de Staphylococcus aureus en muestras de orina.

INTRODUCTION: To evaluate the clinical significance of the isolation of Staphylococcus aureus in urine samples. METHODS: A retrospective study was performed on adult patients identified from a microbiology database in a 200-bed general hospital between the years 2000 and 2009. The demographic data, comorbidities, and risk factors, were reviewed, particularly those associated with the concomitant isolation of S.aureus in blood cultures. RESULTS: The frequency of S.aureus found in urine samples was 0.63%. A total of 43 patients (mean age 68.7 years [SD±16], and 58.1% males) were identified in the database. A Charlson comorbidity index >3 was observed in 20.9%. Concurrent bacteremia was seen in 48.8%. Two groups of patients were distinguished: with concomitant bacteremia (n=21) or without (n=22). Intervention in the urinary tract significantly predicted (P=.00004) bacteriuria without bacteremia (81.8%), compared to bacteremia cases (19%). The attributable mortality was 47.6% in patients with bacteremia compared to non-bacteremia (no deaths), even though the appropriate antibiotic treatment was more frequent among patients with bacteremia (92% and 60%, respectively). CONCLUSION: The presence of S.aureus in urine was accompanied by bacteremia in half of the cases, but in patients without previous urinary tract intervention such a possibility increased to 81%. Concomitant bacteremia predicts a worse prognosis even with appropriate treatment.

[Quinolone resistant Campylobacter jejuni strains isolated from humans and from poultry]. / Cepas de Campylobacter jejuni resistentes a quinolonas aisladas de humanos, gallinas y pollos.

Eight quinolone resistant Campylobacter jejuni strains isolated from humans with diarrheal disease were compared with 23 isolates from chicken and from laying hens. Samples were cultured on selective agar in microaerophilia, identified by conventional tests, and conserved in 17% glycerol at -70 C. Clones were determined by RAPD-PCR employing the 1254 primer (Stern NJ). Five patterns were obtained. Patterns I, II, and V were found in both poultry and human isolates. Pattern I was obtained from poultry in a domestic henhouse. Pattern III was only obtained from humans whereas pattern IV was only obtained from poultry. A 95.3% of clones were found in both, humans and poultry. According to these results colonization by quinolone resistant strains could be the origin of this human infection, acquired by ingestion.

[Two cases of enteritis with bacteremia due to Campylobacter jejuni]. / Dos casos de enteritis con bacteriemia por Campylobacter jejuni.

Campylobacter is an important agent of illness in human beings. Bacteremia occurs principally in the immunocompromissed host and is frequently due to C. fetus. Nevertheless bacteremia also has been observed in patients with enteritis due to C. jejuni. We refer two cases of patients with severe enteritis and bacteremia, both of them with immunosupressive concomitant diseases such as nephrotic syndrome and chronic cirrotic hepatopathy. Both patients presented hemathemesis.

[Prevalence of the bacteria causing diarrea in a Rosario Hospital, Argentina]. / Prevalencia de las bacterias causantes de diarrea en pacientes de un Hospital de Rosario, Argentina.

Bacterial agents causing diarrea in patients attended in a hospital of Rosario, Argentina. The frequency of bacterial agents causing diarrhea can vary in patients of different areas, and through the time. In an epidemiological surveillance we studied 304 patients with diarrheal diseases looking for Salmonella enterica, Shigella spp, Campylobacter spp, Aeromonas spp, Yersinia enterocolitica, and diarrheogenic Escherichia coli. C. jejuni was isolated in 30 patients (9,9 %), Salmonella in 18 (5,9 %), and enteropathogenic E. coli (EPEC) in 7 (2,3 %). Most cases due ton C. jejuni had mucus and/or blood in their feces. Unexpectedly we didn't fine any cases due to Shigella spp. There was much less cases due to EPEC than in our previous studies, and occurred only in children of less than 5 years old. It is necesary to take in consideration that C. jejuni cause nearly all the cases of diarrhea in patients with mucus and blood in their feces actually in our region.

[High relationship between ciprofloxacin use and prevalence of ESBL Klebsiella pneumoniae]. / Alta correlación entre el consumo de ciprofloxacina y la prevalencia de Klebsiella pneumoniae productora de beta-lactamasas de espectro extendido.

BACKGROUND: To assess the relationship between ciprofloxacin use and the prevalence of extended spectrum betalactamases (ESBL) Klebsiella pneumoniae. PATIENTS AND METHODS: Semestral mean values regarding use of antibiotic and prevalence of ESBL Kp were compared during 9 semesters using linear regression and coefficient of correlation. RESULTS: The only statistically significant correlation was ciprofloxacin use and ESBL(+) K. pneumoniae prevalence, with a coefficient of correlation of 0.86 and p = 0.0027 using linear regression. CONCLUSIONS: Ciprofloxacin use must be taking into account when considering infection control programs due to high prevalence rates of ESBL(+) K. pneumoniae in the hospital setting.

Twenty year study of the occurrence of reovirus infection in hospitalized children with acute gastroenteritis in Argentina.

We studied the occurrence of reovirus infection in children hospitalized with acute gastroenteritis in Argentina during a 20-year interval (1981 through 2001). Three of 2854 (0.10%) stools were positive for reovirus but negative for adenovirus, astrovirus and rotavirus. Children infected with reovirus were <1 year old; one had meningoencephalitis in addition to gastroenteritis. This study indicates that reovirus is an uncommon cause of childhood gastroenteritis requires medical assistance.

Argentinean collaborative multicenter study on the in vitro comparative activity of piperacillin-tazobactam against selected bacterial isolates recovered from hospitalized patients.

The in vitro activity of piperacillin-tazobactam and several antibacterial drugs commonly used in Argentinean hospitals for the treatment of severe infections was determined against selected but consecutively isolated strains from clinical specimens recovered from hospitalized patients at 17 different hospitals from 9 Argentinean cities from different geographic areas during the period November 2001-March 2002. Out of 418 Enterobacteriaceae included in the Study 84% were susceptible to piperacillin-tazobactam. ESBLs putative producers were isolated at an extremely high rate since among those isolates obtained from patients with hospital acquired infections 56% of Klebsiella pneumoniae, 32% of Proteus mirabilis and 25% Escherichia coli were phenotypically considered as ESBLs producers Notably P.mirabilis is not considered by for screening for ESBL producers. ESBLs producers were 100% susceptible to imipenem and 70% were susceptible to piperacillin-tazobactam whereas more than 50% were resistant to levofloxacin. The isolates considered as amp C beta lactamase putative producers showed 99% susceptibility to carbapenems while 26.7% were resistant to piperacillin-tazobactam and 38.4% to levofloxacin. Noteworthy only 4% of the Enterobacteriaceae isolates were resistant to amikacin. Piperacillin-tazobactam was the most active agent against Pseudomonas aeruginosa isolates (MIC(90): 128 microg/ml; 78% susceptibility) but showed poor activity against Acinetobacter spp (MIC(90):>256 microg/ml; 21.7% susceptibility). Only 41.7% Acinetobacter spp isolates were susceptible to ampicillin-sulbactam. Piperacillin-tazobactam inhibited 100% of Haemophilus influenzae isolates (MIC(90) < 0.25 microg/ml) but only 16.6% of them were ampicillin resistant. The activity of piperacillin-tazobactam against oxacillin susceptible Staphylococcus aureus or coagulase negative staphylococci was excellent (MIC(90) 2 microg/ml; 100% susceptibility). Out of 150 enterococci 12 isolates (8%) were identified as E.faecium and only three isolates (2%), 2 E.faecium and 1 E.faecalis were vancomycin resistant. All the enterococci isolates were susceptible to linezolid. Piperacillin-tazobactam showed excellent activity (MIC(90) 2 microg/ml; 92% susceptibility). Regarding pneumococci all the isolates showed MICs of 16 microg/ml for piperacillin-tazobactam. Among 34 viridans group streptococci only 67% were penicillin susceptible and 85.2% ceftriaxone susceptible whereas piperacillin-tazobactam was very active (MIC(90) 4 microg/ml).Piperacillin-tazobactam is therefore a very interesting antibacterial drug to be used, preferably in combination (IE: amikacin-vancomycin) for the empiric treatment of severe infections occurring in hospitalized patients in Argentina. Caution must be taken for infections due to ESBL producers considering that the inoculum effect MICs can affect MIC values.

[Effect of alcohol-gel hand hygiene on nosocomial infections due to multi-resistant Klebsiella pneumoniae]. / Efecto del uso de alcohol en gel sobre las infecciones nosocomiales por Klebsiella pneumoniae multirresistente.

Handwashing is considered the most important and effective infection control measure to prevent transmission of nosocomial pathogens. However, compliance with handwashing by health care workers is low. A new modality for hand hygiene is alcohol gel rub, which reduces time required, does not damage the skin and increases health care workers compliance. An observational study was conducted to assess the effect of alcohol-gel hand antiseptic on infection rates due to the 3 more frequent multi-resistant bacteria (Staphylococcus aureus, Klebsiella pneumoniae y Pseudomonas aeruginosa) in our hospital. Two periods were compared, 12 months before and 12 months after starting alcohol gel use. The second period (AG use) showed a significant reduction on incidence rates of Klebsiella pneumoniae with extended spectrum betalactamase (RR: 0.38) overall infections and specially bacteremias (RR: 0.10). Nevertheless, on the basis of this study, we cannot conclude that the result was due to AG itself or to an increase in hand-hygiene compliance.

[Infection outbreak due to resistant Enterococcus faecium to glycopeptides in a Hospital of Rosario, Argentina]. / Brote de infección por Enterococcus faecium resistentes a glicopéptidos en un hospital de Rosario, Argentina.

Enterococci causes serious illness in immunocompromised patients and in severely ill, hospitalized patients. They are commonly isolated from the human gastrointestinal tract, and resistance to vancomycin has increased in frequency during the past few years. We report three cases of nosocomial vancomycin resistant Entrococcus faecium (VRE) infections from September to December of 2000. A 54-year-old man presented post surgical wound infection due to VRE after 2 months of hospitalization. The second is a 65-year-old neutropenic patient with a medical history of acute myeloid leukemia and esophageal carcinoma. In this case, central venous catheter was colonized with EVR. The third, a 65-year-old woman who received therapy with ceftriaxone, ciprofloxacin and clindamicin had a urinary tract infection due to EVR. The three isolates were resistant to vancomycin (MIC value > 256 micrograms/ml). The DNA amplification pattern obtained by OD-PCR were similar in the three cases.

¿Qué tenemos en cuenta al momento de la prescripción de antibióticos? / What do we have in mind at the time of the prescription of antibiotics?

El aumento de la resistencia bacteriana a los antibióticos se ha vuelto un problema global de salud. Entre otros factores, incide la actitud del médico a la hora de indicar tratamiento antibacteriano y en qué medida se basa en la evidencia. Para conocer cómo efectúa sus indicaciones en la práctica diaria se analizaron las respuestas a un cuestionario anónimo formulado a 100 médicos. Se encontraron diferencias en el modo de prescripción entre los facultativos, inclusive tratar con antibióticos sin haber realizado estudio etiológico, así como distinta respuesta de clínicos y cirujanos. Esto pone en evidencia la necesidad de que cada institución de salud disponga de un protocolo para la administración de estos medicamentos (AU)

Recently there has been a dramatic global increase in bacterial resistance. Phisician´s attitude affects the indication of antibacterial treatment. In order to know how they make their indications in daily practice we analyzed the answers to an anonymous questionnaire to 100 MD. Differences were found in the way of prescribing among physicians. Some of them administered antibiotics without having carried out etiological studies. There was also different response from clinicians and surgeons. This highlights the need for each health institution to have a protocol for the administration of these drugs (AU)

[Mycobacterium fortuitum: two patients and the same surgeon]. / Mycobacterium fortuitum: dos pacientes y un mismo cirujano.

We describe two cases of surgical site infections due to Mycobacterium fortuitum after plastic surgery. Both patients were assisted by the same surgeon on differents hospitals. Both patients received combined antibiotic treatment and surgical debridement or multiple aspirative punctures. The final evolutions were satisfactory.

Infección extraintestinal debida a bacterias del género Campylobacter / Extraintestinal infections due to Campylobacter SPP

Campylobacter jejuni causa principalmente enteritis disenteriforme; los casos debidos a C. fetus son raros, mayormente bacteriemiaen inmunosuprimidos. Presentamos dos casos de enfermedad diarreica con bacteriemia, ambos con hemorragia digestiva,debida a C. jejuni, un caso inusual de infección de anerurisma de la arteria femoral y un caso de bacteriemia recurrente conprobable foco en marcapasos en un anciano sin otro factor de inmunosupresión, los dos últimos debidos a C. fetus. Todos lospacientes tuvieron evolución favorable. Recomendamos prestar atención a los hemocultivos que resulten positivos para efectuarlos subcultivos adecuados para recuperar, identificar y determinar la sensibilidad a los antimicrobianos de este tipo de bacterias microaerofílicas.

Campylobacter jejuni often causes enteritis; cases due to C. fetus are rare: it causes mostly bacteremia in patients with immunosuppression.We present two cases of diarrheal disease with bacteremia, both with gastrointestinal bleeding due to C. jejuni, an unusual case ofC. fetus infection of an aneurysm in the femoral artery, and one case of recurrent C. fetus bacteremia with probably focus in apacemaker in an elderly patient without another cause of immunosuppression. All patients had a favorable evolution. We recommendspecial attention to the positive blood cultures in order to recover and identify this type of microaerophilic bacteria, and determineantimicrobial susceptibility.

Immunotherapy with oral, heat-killed, Mycobacterium vaccae in patients with moderate to advanced pulmonary tuberculosis.

A research investigation to evaluate the potential of an oral preparation of Mycobacterium vaccae SRL172 (NCTC 11659) as an immunotherapeutic has been carried out in ten patients with moderate to advanced pulmonary tuberculosis at Carrasco Hospital, Argentina. Comparison was made between oral and injected M.vaccae sharing a mutual control group. Clinical, bacteriological, hematological, radiological and immunological assessments all showed comparable benefits for both injected and oral treatment over those achieved with chemotherapy alone. The only significant difference between results of injected and oral M.vaccae was the failure of the latter to reduce TNF-alpha production by cultured mononuclear cells. A more intensive regime for the oral preparation was used, which as an addition to the directly observed therapy, short-course, treatment should improve results in both drug susceptible and drug-resistant cases. A Phase II Good Clinical Practice trial is now required.

Portación nasal de staphylococcus aureus meticilino resistentes en poblaciones de la comunidad / Nasal colonization with methicillin-resistant staphylococcus aureus in the community

Staphylococcus aureus (SA) causa infecciones graves. Las debidas a cepas resistentes a meticilina representan undesafío terapéutico. Actualmente hay un aumento de casos de infecciones de piel y tejidos blandos con inusitadagravedad debidas a S. aureus meticilinorresistentes adquiridos en la comunidad (SAMR AC) pero se desconoce latasa de colonización de la población sana en nuestro medio. El propósito de este trabajo fue determinar la portación nasal en grupos de deportistas y personas que habitan en residencias de ancianos. Se tomaron hisopados nasales de 332 personas, 180 alojados en 4 residencias de ancianos y 152 de 7 grupos de deportistas, los cuales fueron extraídos, conservados y cultivados por los métodos convencionales. La caracterización molecular fue efectuada por PCR buscando el tipo de cassette cromosómico estafilocócico con el gen mecA (SCCmecA) y el gen que codifica la leucocidina de Panton-Valentine. Se asiló SA en 83 pacientes (25%), de los cuales 40 fueron SA meticilinosensibles (21,1%) y 13 SAMR (3,9%). Ocho casos fueron clasificados fenotípicamente y genotípicamente como SAMR AC (2,4%). Todos tenían SCCmecA tipo IV. Es necesaria una atenta vigilancia ya que las infecciones de piel y tejidos blandos de la comunidad no deberían ser tratadas con antibióticos betalactámicos

Staphylococcus aureus isolates are common causes of skin and soft tissue infections and other invasive infections. Those due to methicillin resistant strains represent a therapeutic challenge. Currently there is an increase in cases due to community-acquired methicillin-resistant S. aureus (CA-MRSA) but the rate of colonization of the healthy population is unknown in our country. The purpose of this study was to determine nasal carriage in sportsmen and people living in nursing homes in Rosario. Nasal swabs of 101 people staying in 4 nursing homes and of 98 from 7 groups of athletes were obtained. The samples were extracted, preserved, and cultured by conventional methods. PCR was performed in order to study the type of staphylococcal chromosome cassette mecA (SCCmecA) gene and the gene encoding the Panton-Valentine leukocidin. S. aureus was isolated in 48 patients (24.1%), of which 40 were methicillin-sensitive S. Aureus (20.1 %), and 8 methicillin resistant S. aureus (4.0%). Five cases were characterized phenotypically and genotypically as CA-MRSA (2.5%). All of them had type IV SCCmecA. Careful surveillance is required because skin and soft tissue infections in the community should not be treated with beta-lactam antibiotics

Cepas de Campylobacter jejuni resistentes a quinolonas aisladas de humanos, gallinas y pollos / Quinolone resistant Campylobacter jejuni strains isolated from humans and from poultry

Se compararon 8 aislamientos de Campylobacter jejuni provenientes de humanos con enfermedad diarreica aguda, con 23 aislamientos de cloaca de gallinas y pollos obtenidos de zonas próximas a la ciudad de Rosario, todos resistentes a la ciprofloxacina. Las muestras se sembraron en agar selectivo y se incubaron en microaerofilia a 42 °C. Las colonias se identificaron con el método tradicional. Los aislamientos se conservaron a -70 °C en caldo cerebro corazón con 17% v/v de glicerina. La clonalidad se determinó por RAPD-PCR, utilizando el primer 1254 (Stern NJ). Se interpretaron los aislamientos como clones distintos cuando diferían en una banda de amplificación. Se obtuvieron 5 clones diferentes. Los patrones I, II y V fueron aislados en criaderos industriales de pollos y en humanos (el II también en un establecimiento de gallinas ponedoras de huevos). En un gallinero familiar se obtuvo el patrón I. El patrón III sólo se obtuvo de humanos. El patrón IV se halló en uno de los criaderos pero no en humanos. Se pudo determinar que 93.5% de las cepas se aislaron tanto de animales como de humanos, por lo que se considera posible que la colonización de criaderos con cepas resistentes a los antimicrobianos pudiera ser el origen de la infección de humanos.

Eight quinolone resistant Campylobacter jejuni strains isolated from humans with diarrheal disease were compared with 23 isolates from chicken and from laying hens. Samples were cultured on selective agar in microaerophilia, identified by conventional tests, and conserved in 17% glycerol at -70 °C. Clones were determined by RAPD-PCR employing the 1254 primer (Stern NJ). Five patterns were obtained. Patterns I, II, and V were found in both poultry and human isolates. Pattern I was obtained from poultry in a domestic henhouse. Pattern III was only obtained from humans whereas pattern IV was only obtained from poultry. A 95.3% of clones were found in both, humans and poultry. According to these results colonization by quinolone resistant strains could be the origin of this human infection, acquired by ingestion.

[Risk factors associated with ceftazidime-resistant Klebsiella pneumoniae infection]. / Factores de riesgo asociados a infecciones por Klebsiella pneumoniae resistentes a ceftacidima.

INTRODUCTION: Risk factors associated with ceftazidime-resistant Klebsiella pneumoniae (CAZ-R Kp) infection may vary among hospitals and in the same hospital at different time points. Knowledge of these factors is required to establish suitable infection control programs. METHODS: A case-control study was conducted to assess risk factors for CAZ-R Kp infection. Thirty-two cases were compared with 28 controls admitted to a 200-bed general hospital during 1999 and 2000. RESULTS: In the univariate analysis Kp CAZ-R isolates were significantly associated with nosocomial acquisition (OR 5 17.40), prior antibiotic use (OR 5 14.94), particularly ciprofloxacin use (OR 5 5), and hospitalization stay of more than 6 days (OR 5 6.72). Significantly associated variables in the logistic regression analysis included nosocomial acquisition (OR 5 9.29), prior antibiotic use (OR 5 6.21), and particularly, ciprofloxacin use (OR 5 10.84). CONCLUSIONS: Efforts toward more rational overall antibiotic use and particularly ciprofloxacin use, combined with infection control measures are necessary to decrease the prevalence of CAZ-R Kp in our hospital.

Significado clínico del aislamiento de Staphylococcus aureus en muestras de orina / Clinical significance of Staphylococcus aureus in urine

Introducción Evaluación del significado clínico del aislamiento de Staphylococcus aureus en muestras de orina. Métodos Se realizó un estudio retrospectivo en pacientes adultos identificados, entre los años 2000 y 2009, de la base de datos de microbiología en un hospital general de 200 camas. Se revisaron variables demográficas, comorbilidad y factores de riesgo, especialmente los vinculados con el aislamiento concomitante de S. aureus en sangre. Resultados La frecuencia de S. aureus en muestras de orina positivas fue del 0,63%. Cuarenta y tres pacientes fueron identificados, con una edad promedio de 68,7 años (DE ± 16), de los cuales el 58,1% fueron varones. Un índice de comorbilidad de Charlson > 3 se observó en el 20,9%. La presencia de bacteriemia simultánea se observó en el 48,8%. Se distinguieron 2 grupos de pacientes según tuvieran bacteriemia concomitante (n = 21) o no (n = 22). La instrumentación de la vía urinaria predijo significativamente (p = 0,00004) la bacteriuria sin bacteriemia (81,8%) comparada con casos bacteriémicos (19%). La mortalidad atribuible fue del 47,6% en los casos con bacteriemia comparada con los no bacteriémicos (sin muertes), aun cuando el tratamiento antibiótico adecuado fue más frecuente entre los pacientes con bacteriemia (92 y 60%, respectivamente). Conclusiones La presencia de S. aureus en orina se acompaña de bacteriemia en la mitad de los casos, y la ausencia de instrumentación previa aumenta esa posibilidad al 81%. La bacteriemia concomitante alerta sobre un peor pronóstico aun con tratamiento adecuado(AU)

Introduction To evaluate the clinical significance of the isolation of Staphylococcus aureus in urine samples. Methods A retrospective study was performed on adult patients identified from a microbiology database in a 200-bed general hospital between the years 2000 and 2009. The demographic data, comorbidities, and risk factors, were reviewed, particularly those associated with the concomitant isolation of S. aureus in blood cultures. Results The frequency of S. aureus found in urine samples was 0.63%. A total of 43 patients (mean age 68.7 years [SD ± 16], and 58.1% males) were identified in the database. A Charlson comorbidity index > 3 was observed in 20.9%. Concurrent bacteremia was seen in 48.8%. Two groups of patients were distinguished: with concomitant bacteremia (n = 21) or without (n = 22). Intervention in the urinary tract significantly predicted (P = .00004) bacteriuria without bacteremia (81.8%), compared to bacteremia cases (19%). The attributable mortality was 47.6% in patients with bacteremia compared to non-bacteremia (no deaths), even though the appropriate antibiotic treatment was more frequent among patients with bacteremia (92% and 60%, respectively). Conclusion The presence of S. aureus in urine was accompanied by bacteremia in half of the cases, but in patients without previous urinary tract intervention such a possibility increased to 81%. Concomitant bacteremia predicts a worse prognosis even with appropriate treatment(AU)

Alta correlación entre el consumo de ciprofloxacina y la prevalencia de Klebsiella pneumoniae productora de ß-lactamasas de espectro extendido / High relationship between ciprofloxacin use and prevalence of ESBL Klebsiella pneumoniae

Background: To assess the relationship between ciprofloxacin use and the prevalence of extended spectrum betalactamases (ESBL) Klebsiella pneumoniae. Patients and Methods: Semestral mean values regarding use of antibiotic and prevalence of ESBL Kp were compared during 9 semesters using linear regression and coefficient of correlation. Results: The only statistically significant correlation was ciprofloxacin use and ESBL(+) K. pneumoniae prevalence, with a coefficient of correlation of 0.86 and p = 0.0027 using linear regression. Conclusions: Ciprofloxacin use must be taking into account when considering infection control programs due to high prevalence rates of ESBL(+) K. pneumoniae in the hospital setting.

Fundamento: Evaluar la correlación entre el consumo de cefalosporinas de tercera generación y ciprofloxacina con la prevalencia de cepas de Klebsiella pneumoniae productoras de ß-lactamasas de espectro extendido (BLEE). Pacientes y Métodos: Los valores promedios semestrales, correspondientes a consumo y prevalencia se compararon durante 9 semestres, usando coeficiente de correlación y regresión lineal. Resultados: La única asociación que resultó estadísticamente significativa, fue la correspondiente al consumo de ciprofloxacina y K. pneumoniae BLEE (+), con un coeficiente de correlación de 0,86 y una p de 0,0027, en el análisis de regresión lineal. Conclusiones: El consumo de ciprofloxacina debe ser tenido en cuenta al momento de establecer programas de control de infecciones frente a elevadas tasas de prevalencia de K. pneumoniae productoras de BLEE en un hospital.

Estudio de un brote debido a aislados de Klebsiella pneumoniae productores de betalactamasas de espectro extendido en un centro asistencial de Rosario - Argentina / An outbreak of extended spectrum beta-lactamase Klebsiella pneumoniae producers in a health care center from Rosario - Argentina

En América Latina (AL) son trascendentes los productores de betalactamasas de espectro extendido (BLEE) en infecciones hospitalarias. Los datos de API y SENTRY revelan una incidencia del 22 a 55. En AL y frecuentemente en el Cono Sur predominan las BLEE de la familia CTX-M contrariamente a EUA y Europa donde prevalecen las derivadas de TEM. Las CTX-M afectan cefotaxima, ceftriaxona y cefepima con más frecuencia que ceftacidima. El tratamiento depende del empleo de carbapenemes con el riesgo de seleccionar resistencia en bacilos gram negativos no fermentadores. El uso de otros betalactámicos particularmente cefepima no es aconsejable por las frecuentes fallas observadas en nuestro medio debido al efecto inóculo por aislados productores de CTX-M-2. Describimos un brote por Klebsiella pneumoniae (Kp) ocurrido entre junio-julio 2004. En el período previo, sólo un paciente presentó una infección debida a Kp productora de BLEE y en el posterior, lo presentaron dos pacientes Se determinó la CIM por microdilución en agar. El fenotipo BLEE se sospechó por ensayo del efecto del clavulanato unido a cefalosporinas de 3ª generación (C3G). Se determinó el punto isoeléctrico (pI) y la detección por PCR del tipo molecular por métodos convencionales. Se comprobaron dos bandas pI 5.4 y 8.2 con ampicilina y ceftriaxona en todas las cepas excepto en dos. Todas las cepas revelaron producción de CTX-M-2 excepto en dos cepas que se identificaron como productoras de SHV-5. Los estudios clonales se correspondieron con los moleculares identificándose dos clones. El brote se resolvió usando dos importantes medidas: 1) lavado de manos y otras medidas de barrera y 2) restringiendo el uso de C3G y ciprofloxacina

Importance of hand germ contamination in health-care workers as possible carriers of nosocomial infections

The importance of hands in the transmission of nosocomial infection has been world wide admitted. However, it is difficult to induce this behavior in health-care workers. The aim of the present work was to point out the importance of hand bacteria colonization, the influence of hand washing and of patient physical examination. One hundred health-care workers were randomly divided in two groups: Group A without hand washing previous to patient physical examination or handling (PPE); group B with hand washing previous to PPE. Direct fingerprint samples in Columbia agar before and after PPE were obtained. The colonies were counted and identified by conventional techniques, and antibiograms according to NCCLS were performed. Before PPE group A participants showed a high number of bacteria regarding group B participants (73.9 Vs 20.7; p < 0.001); 44 out of 50 participants were carriers of potentially pathogen bacteria. No group B participants were carriers of potential pathogen bacteria before PPE. The latter group showed an increase in number of bacteria after PPE (20.7 CFU (before) Vs 115.9 CFU (after); p < 0.001). Sixteen group B participants were contaminated after PPE with potential pathogens such as S. aureus (50 percent of them meticillin resistant); Escherichia coli, Pseudomonas aeruginosa and Enterococcus faecalis, half of them multiresistant. We can conclude on the importance of these results to implement educational programs and to provide the health-care workers with the proper commodities to fulfill this practice