Deciphering Multidrug-Resistant Acinetobacter baumannii from a Pediatric Cancer Hospital in Egypt.

Infection by multidrug-resistant (MDR) Acinetobacter baumannii is one of the major causes of hospital-acquired infections worldwide. The ability of A. baumannii to survive in adverse conditions as well as its extensive antimicrobial resistance make it one of the most difficult to treat pathogens associated with high mortality rates. The aim of this study was to investigate MDR A. baumannii that has spread among pediatric cancer patients in the Children's Cancer Hospital Egypt 57357. Whole-genome sequencing was used to characterize 31 MDR A. baumannii clinical isolates. Phenotypically, the isolates were MDR, with four isolates showing resistance to the last-resort antibiotic colistin. Multilocus sequence typing showed the presence of eight clonal groups, two of which were previously reported to cause outbreaks in Egypt, and one novel sequence type (ST), Oxf-ST2246. Identification of the circulating plasmids showed the presence of two plasmid lineages in the isolates, strongly governed by sequence type. A large number of antimicrobial genes with a range of resistance mechanisms were detected in the isolates, including ß-lactamases and antibiotic efflux pumps. Analysis of insertion sequences (ISs) revealed the presence of ISAba1 and ISAba125 in all the samples, which amplify ß-lactamase expression, causing extensive carbapenem resistance. Mutation analysis was used to decipher underlying mutations responsible for colistin resistance and revealed novel mutations in several outer membrane proteins, in addition to previously reported mutations in pmrB. Altogether, understanding the transmissibility of A. baumannii as well as its resistance and virulence mechanisms will help develop novel treatment options for better management of hospital-acquired infections. IMPORTANCE Acinetobacter baumannii represents a major health threat, in particular among immunocompromised cancer patients. The rise in carbapenem-resistant A. baumannii, and the development of resistance to the last-resort antimicrobial agent colistin, complicates the management of A. baumannii outbreaks and increases mortality rates. Here, we investigate 31 multidrug resistant A. baumannii isolates from pediatric cancer patients in Children's Cancer Hospital Egypt (CCHE) 57357 via whole-genome sequencing. Multilocus sequence typing (MLST) showed the presence of eight clonal groups including a novel sequence type. In silico detection of antimicrobial-resistant genes and virulence factors revealed a strong correlation between certain virulence genes and mortality as well as several point mutations in outer membrane proteins contributing to colistin resistance. Detection of CRISPR/Cas sequences in the majority of the samples was strongly correlated with the presence of prophage sequences and associated with failure of bacteriophage therapy. Altogether, understanding the genetic makeup of circulating A. baumannii is essential for better management of outbreaks.

Protective effect of SARS-CoV-2 preventive measures against ESKAPE and Escherichia coli infections.

BACKGROUND/OBJECTIVES: We investigated whether behavioral precautions adopted during Coronavirus disease (COVID-19) pandemic also influenced the spreading and multidrug resistance (MDR) of ESKAPEEc (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii [AB], Pseudomonas aeruginosa, Enterobacter spp and Escherichia Coli, [EC]) among Intensive Care Unit (ICU) patients. SUBJECTS/METHODS: We performed a single-center retrospective study in adult patients admitted to our COVID-19-free surgical ICU. Only patients staying in ICU for more than 48 hours were included. The ESKAPEEc infections recorded during the COVID-19 period (June 1, 2020 - February 28, 2021) and in the corresponding pre-pandemic period (June 1, 2019 - February 28, 2020) were compared. An interrupted time series analysis was performed to rule out possible confounders. RESULTS: Overall, 173 patients in the COVID-19 period and 132 in the pre-COVID-19 period were investigated. The ESKAPEEc infections were documented in 23 (13.3%) and 35 (26.5%) patients in the pandemic and the pre-pandemic periods, respectively (p = 0.005). Demographics, diagnosis, comorbidities, type of surgery, Simplified Acute Physiology Score II, length of mechanical ventilation, hospital and ICU length of stay, ICU death rate, and 28-day hospital mortality were similar in the two groups. In comparison with the pre-pandemic period, no AB was recorded during COVID-19 period, (p = 0.017), while extended-spectrum beta-lactamase-producing EC infections significantly decreased (p = 0.017). Overall, the ESKAPEEc isolates during pandemic less frequently exhibited multidrug-resistant (p = 0.014). CONCLUSIONS: These findings suggest that a robust adherence to hygiene measures together with human contact restrictions in a COVID-19 free ICU might also restrain the transmission of ESKAPEEc pathogens.

Prevalence and molecular analysis of multidrug-resistant Acinetobacter baumannii in the extra-hospital environment in Mthatha, South Africa

ABSTRACT Introduction: The presence of Acinetobacter baumannii outside hospitals remains unclear. This study aimed to determine the prevalence of multidrug-resistance (MDR) A. baumannii in the extra-hospital environment in Mthatha, South Africa and to investigate the frequency of carbapenemase-encoding genes. Material and Methods: From August 2016 to July 2017 a total of 598 abattoir samples and 689 aquatic samples were collected and analyzed presumptively by cultural methods for the presence of A. baumannii using CHROMagar™ Acinetobacter medium. Species identification was performed by autoSCAN-4 (Dade Behring Inc., IL) and confirmed by the detection of their intrinsic blaOXA-51 gene. Confirmed MDR A. baumannii isolates were screened for the presence of carbapenemase-encoding genes, ISAba1 insertion sequence and integrase intI1. Results: In total, 248 (19.3%) Acinetobacter species were isolated. Acinetobacter. baumannii was detected in 183 (73.8%) of which 85 (46.4%) and 98 (53.6%) were recovered from abattoir and aquatic respectively. MDR A. baumannii was detected in 56.5% (48/85) abattoir isolates and 53.1% (52/98) aquatic isolates. Isolates showed high resistance to antimicrobials most frequently used to treat Acinetobacter infections such as piperacillin/tazobactam; abattoir (98% of isolates resistant), aquatic (94% of isolates resistant), ceftazidime (84%, 83%), ciprofloxacin (71%, 70%), amikacin (41%, 42%), imipenem (75%, 73%), and meropenem (74%, 71%). All the isolates were susceptible to tigecycline and colistin. All the isolates carried blaOXA-51-like. The blaOXA-23 was detected in 32 (66.7%) abattoir isolates and 11 (21.2%) aquatic isolates. The blaOXA-58-like was positive in 7 (14.6%) and 4 (7.7%) abattoir and aquatic isolates, respectively. Both groups of isolates lacked blaOXA-24-like, blaIMP-type, blaVIM-type, blaNDM-1, blaSIM, blaAmpC, ISAba1 and inI1. Isolates showed high level of Multiple Antibiotic Resistance Index (MARI) ranging from 0.20-0.52. Conclusion: Extra-hospital sources such as abattoir and aquatic environments may be a vehicle of spread of MDR A. baumannii strains in the community and hospital settings.

Acinetobacter baumannii can be transferred from contaminated nitrile examination gloves to polypropylene plastic surfaces.

BACKGROUND: Several observational studies suggest that gloves of health care workers are major routes of multidrug-resistant Acinetobacter baumannii transmission. However, limited experimental data are available assessing Acinetobacter transmission from gloves to environmental surfaces. This study determined whether A baumannii was easily transferred from nitrile gloves to polypropylene plastic compared with other gram-negative bacteria that cause health care-associated infections in laboratory-controlled experiments. METHODS: Gloved fingerpad-to-fomite transfer efficiency was determined for drug-resistant and -sensitive strains of A baumannii, Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, and Pseudomonas aeruginosa. RESULTS: Only A baumannii transferred from gloves to fomites 3 minutes after the bacterial transfer event. Transfer efficiency of A baumannii was 0.1%-33% at that time point. DISCUSSION: Bacterial transfer from contaminated gloves to the hospital environment may be related to the type of contaminating bacteria, inoculated bacterial level, fomites, and glove materials. Therefore, it is important to need a comprehensive assessment of the transfer efficiency. CONCLUSIONS: A baumannii can transfer easily from nitrile gloves to fomite compared with other gram-negative bacteria that cause health care-associated infections. These findings support data from previous observational studies that gloves of health care workers can be major routes of A baumannii transmission in clinical settings.

Environmental colonization and onward clonal transmission of carbapenem-resistant Acinetobacter baumannii (CRAB) in a medical intensive care unit: the case for environmental hygiene.

Background: In May 2015, we noticed an increase in carbapenem-resistant Acinetobacter baumannii (CRAB) infections in the Medical Intensive Care Unit (MICU). To investigate this, we studied the extent of environmental contamination and subsequent onward clonal transmission of CRAB. Methods: We conducted a one-day point prevalence screening (PPS) of the patients and environment in the MICU. We screened patients using endotracheal tube aspirates and swabs from nares, axillae, groin, rectum, wounds, and exit sites of drains. We collected environmental samples from patients' rooms and environment outside the patients' rooms. CRAB isolates from the PPS and clinical samples over the subsequent one month were studied for genetic relatedness by whole genome sequencing (WGS). Results: We collected 34 samples from seven patients and 244 samples from the environment. On the day of PPS, we identified 8 CRAB carriers: 3 who screened positive and 5 previously known clinical infections. We detected environmental contamination in nearly two-thirds of the rooms housing patients with CRAB. WGS demonstrated genetic clustering of isolates within rooms but not across rooms. We analysed 4 CRAB isolates from clinical samples following the PPS. One genetically-related CRAB was identified in the respiratory sample of a patient with nosocomial pneumonia, who was admitted to the MICU five days after the PPS. Conclusion: The extensive environmental colonization of CRAB by patients highlights the importance of environmental hygiene. The transmission dynamics of CRAB needs further investigation.

Identifying more epidemic clones during a hospital outbreak of multidrug-resistant Acinetobacter baumannii.

Infections caused by multidrug-resistant bacteria are a major concern in hospitals. Current infection-control practices legitimately focus on hygiene and appropriate use of antibiotics. However, little is known about the intrinsic abilities of some bacterial strains to cause outbreaks. They can be measured at a population level by the pathogen's transmission rate, i.e. the rate at which the pathogen is transmitted from colonized hosts to susceptible hosts, or its reproduction number, counting the number of secondary cases per infected/colonized host. We collected data covering a 20-month surveillance period for carriage of multidrug-resistant Acinetobacter baumannii (MDRAB) in a surgery ward. All isolates were subjected to molecular fingerprinting, and a cluster analysis of profiles was performed to identify clonal groups. We then applied stochastic transmission models to infer transmission rates of MDRAB and each MDRAB clone. Molecular fingerprinting indicated that 3 clonal complexes spread in the ward. A first model, not accounting for different clones, quantified the level of in-ward cross-transmission, with an estimated transmission rate of 0.03/day (95% credible interval [0.012-0.049]) and a single-admission reproduction number of 0.61 [0.30-1.02]. The second model, accounting for different clones, suggested an enhanced transmissibility of clone 3 (transmission rate 0.047/day [0.018-0.091], with a single-admission reproduction number of 0.81 [0.30-1.56]). Clones 1 and 2 had comparable transmission rates (respectively, 0.016 [0.001-0.045], 0.014 [0.001-0.045]). The method used is broadly applicable to other nosocomial pathogens, as long as surveillance data and genotyping information are available. Building on these results, more epidemic clones could be identified, and could lead to follow-up studies dissecting the functional basis for variation in transmissibility of MDRAB lineages.

Bacterial contamination of the hospital environment during wound dressing change.

INTRODUCTION: The hospital environment plays a role in the cross-transmission of multidrug-resistant bacteria. The aim of this study was to evaluate the bacterial contamination of the hospital environment during chronic wound dressing change. PATIENTS AND METHODS: This study was performed from July 2010 to May 2011. Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii and Enterobacteriaceae were counted in environmental samples (air and surfaces) that were obtained in the rooms of patients with wounds colonized (cases, n=9) or not (controls, n=15) during or not during wound dressing change. Bacterial contamination was compared to that found in the rooms of patients without colonized wounds. RESULTS: The environment was frequently contaminated during wound dressing change (38% of the sampled series were positive). In comparison, the contamination was less frequent in the environment of patients with colonized wounds when the wounds were not being dressed (14.3%) and in controls (3.8%). S. aureus was the most frequent species identified in positive samples. DISCUSSION: These results suggest that previously recommended measures such as hand hygiene after contact with the environment and wearing a mask are justified. Moreover, other measures should be suggested, in particular cleaning the room before and after dressing change of colonized wounds. LEVEL OF EVIDENCE: Level III: case control study.

The transmission of nosocomial pathogens in an intensive care unit: a space-time clustering and structural equation modelling approach.

We investigated the incidence of cases of nosocomial pathogens and risk factors in an intensive treatment unit ward to determine if the number of cases is dependent on location of patients and the colonization/infection history of the ward. A clustering approach method was developed to investigate the patterns of spread of cases through time for five microorganisms [methicillin-resistant Staphylococcus aureus (MRSA), Acinetobacter spp., Klebsiella spp., Candida spp., and Pseudomonas aeruginosa] using hospital microbiological monitoring data and ward records of patient-bed use. Cases of colonization/infection by MRSA, Candida and Pseudomonas were clustered in beds and through time while cases of Klebsiella and Acinetobacter were not. We used structural equation modelling to analyse interacting risk factors and the potential pathways of transmission in the ward. Prior nurse contact with colonized/infected patients, mediated by the number of patient-bed movements, were important predictors for all cases, except for those of Pseudomonas. General health and invasive surgery were significant predictors of cases of Candida and Klebsiella. We suggest that isolation and bed movement as a strategy to manage MRSA infections is likely to impact upon the incidence of cases of other opportunist pathogens.

Transmissão de acinetobacter baumannii resistente em uma unidade de terapia intensiva: abordagem do ambiente e da higiene das mãos através de um modelo matemático determinístico / Transmission of resistant acinetobacter baumannii in an intensive care unit: approach to environmental and hand hygiene through a deterministic mathematical model

Introdução: Acinetobacter baumannii emergiu nos últimos trinta anos como umpatógeno relevante para ocorrência de infecções graves em pacientes gravemente comprometidos pela doença de base. Altas taxas de morbi-mortalidade são associadas às cepas resistentes de A. baumannii, as quais podem manter comportamento epidêmicocausando surtos extensos simultaneamente em diversas instituições de saúde. Historicamente A. baumannii tem habilidade para persistir em ambientes secos e úmidos, o que torna o controle de disseminação de difícil execução Tanto a higienizaçãodas mãos quanto a limpeza rigorosa do ambiente são estratégias fundamentais a serem adotadas para essa finalidade. Objetivo: identificar através de simulações do modelo a relação entre o tempo de contaminação do ambiente e o risco de disseminação de Acinetobacter baumannii resistente e a relação entre inadequação da higienização das mãos pelos profissionais de saúde e o risco de disseminação de Acinetobacter baumannii resistente. Materiais e Métodos: um modelo matemático determinístico foi elaborado para avaliar a dinâmica de transmissão de A. baumannii dentro de uma unidade de terapia intensiva hipotética. O comportamento das variáveis de interesse foi simulado ao longo do tempo para diferentes valores dos parâmetros inadequação da higienização das mãos e descontaminação do ambiente. As prevalências dosindivíduos suscetíveis, colonizados e infectados foram avaliadas. O software utilizado foi o XPP/WinPP. Resultados: após várias simulações do modelo onde as duas variáveis de interesse foram simultaneamente avaliadas, o modelo prediz que melhores resultados na prevalência de indivíduos colonizados e infectados (baixa prevalência de colonizados e infectados em comparação com o modelo original =0,4 e =0,1]), são encontrados quando profissionais de saúde aderem mais à prática de higienização das mãos (=0,1) associada à rápida descontaminação do ambiente (>0,1)...

Introduction: Acinetobacter baumannii has emerged over the last thirty years as an important pathogen for the occurrence of serious infections in patients severely compromised by underlying disease. High rates of morbidity and mortality are associated with resistant strains of A.baumannii, which can maintain epidemic behaviorcausing large outbreaks in various health institutions simultaneously. Historically, A. baumannii is able to survive under dry and humid environments, which makes difficult to control its spread. Both hand washing and rigorous environmental cleaningare key strategies to be adopted for this purpose. Objective: To identify throughsimulations model the environment contamination time which contributes to further spread of resistant Acinetobacter baumannii and hand hygiene adherence rate of healthprofessionals that predicts the best spread control of resistant Acinetobacterbaumannii. Materials and methods: A deterministic mathematical model wasdeveloped to assess the dynamic transmission of A. baumannii in a hypothetical critical care unit. The behavior of variable of interest was simulated over time for differentparameters values inadequate handwashing and decontamination of the environment. The prevalence of susceptible, colonized and infected individuals, was evaluated. It was utilized the software XPP/WinPP. Results: After several model simulations where the two variables of interest were simultaneously evaluated, the model predicts that better results in the prevalence of colonized and infected individuals (low prevalence ofcolonized and infected individuals compared to the original model [ =0,4 and =0,1]), are found when health professionals have higher adherence to hand hygiene practice ( =0,1) associated with the rapid decontamination of the environment( >0,1)...

Preventing strategy of multidrug-resistant Acinetobacter baumanii susceptible only to colistin in cardiac surgical intensive care units.

OBJECTIVE: The study aimed to determine the incidence and mortality of multidrug-resistant Acinetobacter baumannii in cardiac surgery, to elucidate the effectiveness of colistin treatment and to identify if the additional measures to the recommended procedures were able to control the dissemination of the pathogen. METHODS: A prospective observational cohort was conducted among cardiac surgical patients from 1 September 2005 to 31 December 2006. We reviewed the prophylactic measures of the surgical intensive care unit and implemented a two scale multiple program. Scale I included classical infection control measures, while Scale II referred to the geographic isolation of multidrug-resistant Acinetobacter baumannii patients and environmental intense surveillance. RESULTS: Among 151 out of 1935 infected patients 20 were colonized and infected by strains of multidrug-resistant A. baumannii susceptible only to colistin. Seventeen patients presented respiratory tract infection, one patient suffered deep surgical site infection and two patients catheter related infection. Transmission of the pathogen occurred via two patients transferred from two other institutions. They were all treated with colistin. Cure or clinical improvement was observed only in four patients (20%). Scale I measures were implemented for the whole 16-month period while scale II for two separate periods of 3 weeks. Environmental specimens (n>350) proved negative. CONCLUSIONS: The increasing prevalence of multidrug-resistant A. baumannii in surgical intensive care unit patients creates demand on strict screening and contact precautions. Following this infection control strategy we were able to achieve intermittent eradication of the pathogen during a 16-month period with continuous function of the intensive care unit. Despite the significant in vitro activity of colistin against multidrug-resistant Acinetobacter baumannii the results were discouraging.

Comportamiento de acinobacter en los procesos infecciosos de los pacientes ingresados al HEALF de enero 2004 a diciembre de 2005 / Acinobacter behavior in the infectious processes of the patients entered the HEALF of January 2004 to December of 2005

El trabajo comportamiento de acinetobacter en los procesos infecciosos de pacientes ingresados al HEALF de enero de 2004- diciembre de 2005, se realizó con el objetivo de conocer el comportamiento de esta bacteria en nuestro medio ya que el acinetobacter ha surgido como un importante microorganismo a nivel intrahospitalario y uno de los mayores problemas de la infecciones producidas por esta bacteria es su tratamiento, por su amplia multiresistencia y por las pocas alternativas terapéuticas disponibles en la actualidad. Dicho estudio es descriptivo, de serie de casos. Para alcanzar este objetivo se estudiaron 452 pacientes a los que se aisló 528 Acinetobacter. Los procesos infewcciosos más frecuentes fueron: Sepsis de Herida Quirúrgica, Neumonías y Traqueóbronquitis. Los servicios más afectados fueron: Medicina Interna y de esta, la sala de UCI (Unidad de cuidados intensivos), Neurocirugía, principalmente lka sala de Neurocirugía Intermedios y cirugía plástica principalmente la sala de quemados. Según los resultados de Antibiogrma se encontró un alto grado de resistencia de la bacteria a los antibióticos disponibles en la Lista Básica de Medicamentos como son: Ceftriazona, Ampicilina, Amikacina, Ceftazidima y en menor grado de resistencia a los Carbapemenes (Imipenem, Meropenem)...>

Metallo-beta-lactamase expressing multi-resistant Acinetobacter baumannii transmitted in the operation area.

Outbreaks of Acinetobacter baumannii demonstrating multiple antibiotic resistance, including meropenem resistance, have been described as severe therapeutic problems. Here we describe a monoclonal outbreak of infection and colonization with multidrug-resistant A. baumannii over a two-month period. Resistance to meropenem was mediated by expression of a metallo-beta-lactamase enzyme. Four of 14 patients showed clinical signs of infection and two died. Contamination of the environment, water, or instruments were excluded as causes of the outbreak. All patients, except one, underwent surgery in a specific operation theatre where surgery of contamination class IV (infected, dirty) was performed. Although individual surgeon error was eliminated, analyses of the patients' histories suggested that bacterial transmission had occurred during surgery. Five patients showed signs of A. baumannii infection and two of these patients suffered from large abdominal wounds infected with a high density of A. baumannii requiring repeated revisions. Presumably, these revisions favoured the transmission of A. baumannii, which is remarkably resistant to various environmental stresses including soaps, disinfectants and dry conditions. No case of meropenem-resistant A. baumannii had been observed in the hospital before the outbreak. Interestingly, the resistant bacteria appear to have been imported by a patient returning from West Africa. This indicates that, similar to MRSA, multiresistant A. baumannii may be introduced by patients from foreign hospitals. The outbreak was stopped in the following months by reinforcing standard procedures and by taking all necessary precautions such as patient isolation, and finally only one new case was detected.

Association of private isolation rooms with ventilator-associated Acinetobacter baumanii pneumonia in a surgical intensive-care unit.

OBJECTIVE: To determine the rates and routes of Acinetobacter baumanii colonization and pneumonia among ventilated patients in a surgical intensive-care unit (SICU) before and after architectural modifications. DESIGN: A nonsequential study comparing two groups of patients. All isolates from systematic and clinical samples were genotyped by pulsed-field gel electrophoresis (PFGE). Records of patients hospitalized during the first and second periods were reviewed and findings were compared. Between the two periods, the SICU was remodeled from enclosed isolation rooms and open rooms to only enclosed isolation rooms with handwashing facilities in each room. SETTING AND PATIENTS: All patients hospitalized and mechanically ventilated for more than 48 hours in the 15-bed SICU of the University Hospital of Besançon (France). RESULTS: For the first and second periods, the rates of colonization were, respectively, 28.1% and 5.0% of patients (P < 10(-7); relative risk [RR], 2.23; 95% confidence interval [CI95], 1.8-2.75) and the specific rates of bronchopulmonary (BP) colonization were, respectively, 9.1 and 0.5 per 1,000 days of mechanical ventilation (P < 10(-5). Seven major PFGE isolate types were identified, 4 of which were isolated from 44 of the 47 colonized or infected patients. Logistic regression analysis showed that colonization was not associated with patient characteristics. CONCLUSION: Conversion from open rooms to isolation rooms may help control nosocomial BP tract acquisition of A baumanii in mechanically ventilated patients hospitalized in an SICU.

Liquid nitrogen freezers: a potential source of microbial contamination of hematopoietic stem cell components.

BACKGROUND: The recent report of hepatitis B transmission between hematopoietic progenitor and putative stem cell (HPC) components stored in liquid nitrogen led to the questioning of whether evidence existed for similar contamination by bacterial or fungal elements. STUDY DESIGN AND METHODS: Microbial contamination rates were reviewed for 704 HPC components from 255 patients over an 18-month period. Five liquid nitrogen freezers were surveyed for microbial contamination. The literature was reviewed to ascertain the published experience of other laboratories with HPC component contamination first documented on thawing. RESULTS: Seven (1.2%) of 583 thawed components were found to be contaminated with a variety of environmental or waterborne organisms, despite a meticulous protocol to prevent contamination during thawing. All of these components had been sterile on cryopreservation. Literature review revealed a similar incidence of post-thaw contamination from other centers. Microbial survey of liquid nitrogen freezers revealed low-level contamination in four of five. The organisms represented were similar to those cultured from thawed HPC components. One freezer was heavily contaminated by Aspergillus species. CONCLUSION: Liquid nitrogen freezers are not sterile, and both the liquid and vapor phases are potential sources of microbial contamination of HPC components. While low-level contamination by environmental organisms may be common, the occurrence of heavy contamination by potential pathogens such as Aspergillus species suggests that monitoring of liquid nitrogen sterility may be indicated. Strategies to assess and prevent microbial transmission from liquid nitrogen to HPC components need further development.

Bacterial contamination and closed suction drainage in open meniscectomy of the knee.

A prospective study was undertaken to investigate the occurrence and possible sources of microbial contamination in association with open meniscectomy of the knee. Sixty patients were randomized into three closed suction drainage regimens of 12, 24 and 48 hours' postoperative suction drainage, respectively. Specimens for bacterial culture were taken from the joint at the time of surgery, from the surgical suction tips, from the subcutaneous part of the drain surface and from the drain-contained fluid at the time of drain removal. The airborne bacterial contamination showed no marked role in this bacterial invasion into the joint, nor did the use of suction increase the risk. The vacuum suction drain, on the other hand, appeared to carry an obvious risk of bacterial invasion, as a parallel of time. In the present comparison this risk was minimal when the drain was removed 12 hours postoperatively.

Acinetobacter en una unidad metropolitana de neonatología: aspectos clínicos y microbiológicos / Acinetobacter in a metropolitan neonatal unit: clinical and microbiological aspects

En marzo de 1989 en la unidad de neonatología del hospital San Juan de Dios se detectó Acinetobacter calcoaceticus subespecie anitratus (ACA) en un RN con infección de la piel circundante de una herida de colostomía. Otro niño, hospitalizado en la misma sala, presentaba colonización de piel con ACA y, dado que requería tratamiento quirúrgico, recibio profilaxis con sulbactam-ampicilina antes y después de la operación. El tercer caso nació el mismo mes, era una RN muy inmadura que sufrió septicemia precoz de Acinetobacter calcoaceticus var.lwoffi susceptible a gentamicina. Tratada con este antibiótico, evolucionó satisfactoriamente. En el control microbiológico de la unidad de neonatología se pesquisó este último microorganismo en los termómetros de la sala de atención inmediata, y en las manos de una auxiliar que la atendió varias semanas, mientras la variedad anitratus había sido detectada el mes anterior en los pabellones quirúrgicos y equipos de anestesia. El control microbiológico y la aplicación en equipo de técnicas de limpieza, aislamiento y lavado de manos adecuados, evitaron probablemente un brote epidémico

Acinetobacter y su control intrahospitalario / Acinetobacter and it intrahospitable control

Acinetobacter es una bacteria Gram negativa no fermentadora, que se ha presentado en numerosos hospitales de nuestro país a partir de mediados de 1988. Es un gérmen patógeno oportunista, agente de infecciones nosocomiales que infecta a huéspedes inmunodeficientes y cuando alcanza localización que son normalmente estériles, a partir de traumatismos y de técnicas invasivas. Este microroganismo es altamente transmisible por vía directa, siendo las manos de las personas del equipo de salud el mayor vehículo de difusión. El problema radica en la alta resistencia antibiótica que presentan algunas cepas; en la mayoría de los casos son sensibles únicamente al ampisulbactan, de aquí la importancia de su prevención y control intrahospitalario

Acinetobacter calcoaceticus ssp. anitratus en la unidad de neonatología del Hospital San Juan de Dios, 1990 / Acinetobacter calcoaceticus ssp. at the unit of neonatology. San Juan de Dios Hospital 1990

En febrero de 1990, en la Unidad de Neonatología del Hospital San Juan de Dios, se detectó A. calcoaceticus ssp. anitratus en un catéter de arteria umbilical. Se trataba de un recién nacido con enfermedad de membrana hialina severa que requirió ventilación mecánica y cateterización de la arteria umbilical. A raiz del caso índice se realizó un estudio microbiológico de la Unidad, encontrándose como reservorio de A. calcoaceticus ssp. anitratus un humidificador de oxígeno y además otros 6 niños con colonización cutánea, 5 de los cuales habían recibido oxigenoterapia. Los niños colonizados se aislaron, se usó povidona yodada local en la piel inguinal, y además el caso índice recibió tratamiento con sulbactam/ampicilina, lográndose evitar un brote epidémico