Sterility of antibiotic-admixed peritoneal dialysis solution over time.

BACKGROUND: Intraperitoneal antibiotics may be required daily for up to three weeks to treat peritoneal dialysis (PD)-related peritonitis. In some jurisdictions, antibiotic-admixed PD solutions are required to be used within 24 h due to concerns regarding microbial contamination and growth. This requires patients to attend the PD unit daily or alternatively for staff to perform home delivery with associated transport, staffing and cost implications. OBJECTIVE: The aim of this study was to determine if significant microbial growth occurs in PD solutions following their injection with antibiotic or sterile water. METHODS: Twelve PD solution bags were admixed with cefazolin sodium 1 g, diluted in 10 mL sterile water, while a further 12 PD solution bags were admixed with 10 mL sterile water using aseptic technique (AT) under supervision. All bags were stored at room temperature. Three bags from each experimental group were sampled for microbiologic culture at 0-, 24-, 48- and 72-h intervals. RESULTS: One sterile water admixed bag sampled at 24 h yielded a Corynebacterium spp. after microbiologic culture. A repeat specimen from the same bag at day nine returned a negative culture result. All other sterile water and cefazolin admixed bags returned negative culture results at all time points. CONCLUSIONS: Antibiotic-admixed PD solutions prepared using AT and stored at room temperature remained sterile for up to 72 h. This suggests that patients can be safely issued with a supply of antibiotic-admixed PD bags for up to three days at a time.

Utilidad diagnóstica de los tiempos de positividad de hemocultivos para distinguir verdaderas bacteriemias de contaminantes en base a un sistema automatizado / Diagnostic performance of the time to positivity of blood cultures to distinguish true bacteremia from contaminants based on an automated system

RESUMEN Objetivo. Determinar la utilidad diagnóstica de los tiempos de positividad de hemocultivos para distinguir verdaderas bacteriemias de contaminantes en el sistema automatizado «BACT/ALERT®¼. Materiales y métodos. Se realizó un estudio transversal de tipo pruebas diagnósticas, a partir de una base de datos de muestras de hemocultivos procesadas entre enero del 2016 y agosto del 2021. Se incluyeron todas las muestras de hemocultivos de pacientes con sospecha de bacteriemia, las muestras de hemocultivos fueron ingresadas al sistema «BACT/ALERT®¼ para diferenciar verdaderas bacteriemias de contaminantes. Resultados. Se analizó un total de 33 951 frascos de hemocultivos y se obtuvieron 3875 frascos positivos. El 75,2% (n=2913) del total de hemocultivos positivos fueron verdaderas bacteriemias y 24,8% (n=962) fueron contaminantes. La mediana de tiempo de positividad en los hemocultivos con verdaderas bacteriemias fue significativamente menor (16,3 horas; RIC: 11,2 - 24,9) que la mediana de tiempo de positividad de hemocultivos con contaminantes (22,5 horas; RIC: 18,4 - 31,8; p<0,001). El tiempo de positividad demostró capacidad discriminante para diferenciar verdaderas bacteriemias de contaminantes, con un AUC-ROC de 0,73 (IC95%: 0,71 - 0,75), con 85% y 63% de sensibilidad y especificidad respectivamente para el diagnóstico de contaminantes cuando el tiempo de positividad supera las 16,5 horas. La administración de antibióticos previos a la toma retrasó el tiempo de positividad, en cambio, haber presentado fiebre antes de la toma de muestra acortó el tiempo de positividad. Conclusiones. Nuestros resultados muestran un buen desempeño de los tiempos de positividad de hemocultivos para diferenciar verdaderas bacteriemias de contaminantes utilizando el sistema «BACT/ALERT®¼ cuando el tiempo de positividad fue superior a 16,5 horas.

ABSTRACT Objective. To determine the diagnostic performance of blood culture positivity times for distinguishing true bacteremia from contaminants in the automated "BACT/ALERT®" system. Materials and methods. A cross-sectional, diagnostic test-type study was conducted from a database of blood culture samples processed between January 2016 and August 2021. All blood culture samples from patients with suspected bacteremia were included; blood culture samples were entered into the "BACT/ALERT®" system to differentiate true bacteremia from contaminants. Results. We obtained 33,951 blood cultures samples, of which 3875 were positive. Of the total number of positive blood cultures, 75.2% (n=2913) were true bacteremia and 24.8% (n=962) were contaminants. The median time to positivity in blood cultures with true bacteremia was significantly shorter (16.3 hours; IQR: 11.2 - 24.9) than the median time to positivity of blood cultures with contaminants (22.5 hours; IQR: 18.4 - 31.8; p<0.001). The positivity time showed the capacity to differentiate true bacteremia from contaminants, with an AUC-ROC of 0.73 (95%CI: 0.71 - 0.75), with 85% and 63% sensitivity and specificity respectively for the diagnosis of contaminants when the positivity time exceeds 16.5 hours. The use of antibiotics prior to sampling delayed the time to positivity, while having fever before sampling shortened the time to positivity. Conclusions. Our results show good diagnostic performance of blood culture positivity times to differentiate true bacteremia from contaminants using the "BACT/ALERT®" system when the positivity time was longer than 16.5 hours.

Microbiological analysis of bacterial sealing of internal conical implants with different taper angles

Abstract The present study evaluated the effect of the taper angle of different internal conical connection implants and cyclic loading on the implant-abutment bacterial seal. A total of 96 implant-abutment sets were divided into eight groups. Four groups of different taper degrees with cyclic mechanical loading of 500,000 cycles per sample, with a 120-N load at 2 Hz before analysis [16DC (16-degree, cycled), 11.5DC (11.5-degree, cycled), 3DC (3- degree, cycled) and 4DC (4- degree, cycled)] were compared to four control groups without cyclic loading [16D (16-degree), 11.5D (11.5-degree), 3D (3-degree), and 4D (4-degree)]. Microbiological analysis was performed by immersing all samples in a suspension containing Escherichia coli and incubating them at 37°C. After 14 days, the presence of bacterial seals was evaluated. Fisher-Freeman-Halton exact tests and binomial tests were performed (5% significance level). The groups showed significant differences in bacterial seal, and mechanical load cycling improved the bacterial seal in the 3DC group. In all other groups, no significant differences in bacterial seal were found between cycled and uncycled samples. To conclude, the internal conical connection with a 3-degree taper angle showed better results than the other connection with different angles when subjected to load cycling. However, none of the angles tested were fully effective in sealing the implant-abutment interface.

Towards the Development of Microbial Ecotoxicology Testing Using Chlorpyrifos Contaminated Sediments and Marine Yeast Isolates as a Model.

Chlorpyrifos (CP), a widely used pesticide, and its metabolite 3,5,6-trichloro-2-pyridinol (3,5,6-TCP), are xenobiotic compounds detected in many biomes, notably in marine sediments, all over the world. These compounds are posing a serious environmental and health problem given their toxicity to wildlife and possible exposure effects to human neurodevelopment. Microorganisms at CP-impacted environments could harbor metabolic capabilities that can be used as indicators of the biological effects of the contaminant and could encode selected functions reactive against contaminants. Those features could be used for microbial ecotoxicology applications by collectively using analytical, enzymatic, microbiological and toxicological techniques in order to assess the biological effects of pollutants and other environmental/climatic stressors in ecosystems. The objective of this study was to assess the variability in the metabolic responses of yeast isolates from CP-contaminated marine sediments as potential biological indicators for microbial ecotoxicology testing. Sediment samples from a South Caribbean tropical shore (Cartagena Bay, Colombia) were collected, and deoxyribonucleic acid (DNA) was recovered from lyophilized aliquots. The DGGE (Denaturing Gradient Gel Electrophoresis) technique targeting fungal Internal Transcribed Spacer (ITS) showed the great diversity of fungal types. Simultaneously, yeast strains were isolated from the freshly collected sediment samples. Physiological characterization including API 20C and antibiosis tests, growth patterns at salt concentrations (2/4/10/25%), temperatures (4/25/37/45 °C), esterase activity assay and resistance tests to CP/TCP toxicity resulted in 10 isolated yeast strains, identified as Candida spp. (6), Cryptococcus spp. (3). and Rhodotorula spp. (1), showing promising characteristics to be used as a test for yeast-based ecotoxicity indicators. The patterns of carbohydrate assimilation, low antibiosis, presence of esterases/lipases, growth in a wide range of temperatures and salt concentrations, and tolerance to minimal inhibitory concentrations of CP and TCP are factors useful for testing environmental samples.

Integrity performance assessment of a closed system transfer device syringe adaptor lock as a terminal closure for Luer-Lock syringes.

OBJECTIVES: To investigate the container closure integrity of a closed system transfer device syringe adaptor lock in combination with disposable Luer-Lock syringes as the terminal closure device. The UK National Health Service (NHS) Pharmaceutical Quality Assurance Committee (PQAC) requires syringe integrity data for final storage devices of aseptic products such as chemotherapy drugs when prepared in advance and stored before use, as is standard practice for dose banded drugs. The assessment comprised both physical and microbial integrity testing of the combination closed system/Luer-Lock syringe containers at syringe sizes of 1 mL, 20 mL, and 50 mL. METHODS: Integrity testing was performed as described in the NHS Pharmaceutical Quality Assurance Committee yellow cover document, second edition 2013 'Protocols for the Integrity Testing of Syringes', with Chemfort (Simplivia, IL) syringe adaptor lock (SAL) devices as replacement for sterile blind hubs. Microbiological integrity was assessed according to method 1 part 1.4 using Brevundimonas diminuta at 32°C for up to 14 days of contact time. Two positive control devices per syringe size were tested using a blind hub cap as closure which was loosened before the test. Physical integrity was assessed using method 3 of the yellow cover document which is a dye intrusion method. Dye intrusion was assessed both visually and using a validated ultraviolet-visible spectrophotometer method. For each size/batch of test articles a positive control device (n=1) was assessed using a wire wrapped around the syringe plunger tip deliberately compromising integrity. Negative controls for each size (n=1) consisted of devices not immersed in methylene blue dye. RESULTS: Chemfort syringe adaptor lock/Luer-Lock syringe combinations were shown to be: (1) free of microbiological contamination after 14 days of contact time (n=60); and (2) free of dye intrusion at all syringe sizes tested (n=61 in total). The data demonstrate 100% closure integrity of the final container system when the Chemfort syringe adaptor lock replaces the syringe hub as the terminal closure device. All positive control devices demonstrated system suitability as container integrity was compromised in all positive control tests. All negative controls were negative for microbial and dye intrusion. CONCLUSIONS: Syringe adaptor lock components complied with the NHS Pharmaceutical Quality Assurance Committee yellow cover document syringe integrity requirements when used as the terminal closure of Luer-Lock disposable syringes from 1 mL up to 50 mL. Therefore, syringe adaptor lock (Chemfort) can be used as the terminal closure system for pre-filled syringes of chemotherapeutic drug products prepared in advance in UK NHS pharmacy technical services.

Conteo de bacterias y levaduras en imágenes digitales

RESUMEN Fundamento: en los laboratorios de microbiología, la identificación y conteo de microorganismos es un procedimiento habitual. Aunque existen en el mercado equipos que posibilitan su realización de manera automática o semiautomática, son muy costosos, por lo cual esta tarea, difícil e irritante para los ojos, la siguen realizando los expertos de manera tradicional mediante la observación de las muestras en los microscopios, con la consiguiente variabilidad entre ellos. Objetivo: proponer un nuevo método para el conteo de bacterias y levaduras en imágenes digitales, bajo diferentes magnificaciones, tomadas a bioproductos de origen microbiano obtenidos por fermentación. Métodos: el sensor empleado para la toma de imágenes de las muestras fue una cámara digital modelo HDCE-X, con un sensor CMOS de ½", con una resolución de 2592 píxeles por 1944 píxeles (5 Mp). Se emplearon dos tipos de magnificaciones: magnificación 40x (PL40, 0.65 apertura numérica and 0.17 de distancia de trabajo) y magnificación 100x (HI plan 100/1.25 con inmersión de aceite). El método propuesto se basa en técnicas de procesamiento digital de imágenes, utilizando herramientas como la detección de contornos, operaciones morfológicas y análisis estadístico, y fue desarrollado en lenguaje Python con empleo de la biblioteca OpenCV. Resultados: la detección y conteo de bacterias se logró con una exactitud y precisión aceptable, en ambos casos por encima de 0,95; no en el caso de las levaduras cuya exactitud y precisión fueron menores, alrededor de 0,78 y 0,86 respectivamente. Se proponen flujos de trabajo basados en técnicas de procesamiento digital de imágenes, fundamentalmente en detección de contornos, operaciones morfológicas y análisis estadístico. Conclusiones: el método posee una efectividad aceptable para el contexto y depende de las características que presenten las imágenes.

ABSTRACT Background: In microbiology laboratories, the identification and counting of microorganisms is a common procedure; and although there is a variety of equipment on the market that possibility to carry out these processes automatically or semi-automatically, it is usually expensive to many laboratories. These are some of the reasons why this arduous and difficult task is still performed in many laboratories by experts in the traditional way, through the observation of samples in microscope, consuming a great time and having variations in the results between experts. Objective: The present work aims to propose a new method for counting bacteria and yeasts in digital images, taken under different magnifications, of microbial bioproducts obtained by fermentation. Methods: The sensor used to take images of the samples was a digital camera model HDCE-X, with a ½" CMOS sensor, with a resolution of 2592 pixels by 1944 pixels (5 Mp). Two types of magnifications were used: 40x magnification (PL40, 0.65 numerical aperture and 0.17 working distance) and 100x magnification (HI plan 100/1.25 with oil immersion). The proposed method is based on digital image processing technics, using tools as contour detection, morphological operations and statistical analysis, and was developed in Python language using the OpenCV library. The work also presents a comparison with the results obtained using ImageJ software for the same purpose. Results: the detection and count of bacteria was achieved with an acceptable accuracy and precision, in both cases above 0.95; not in the case of yeasts whose accuracy and precision was lower, around 0.78 for accuracy and 0.86 for precision. Workflows based on digital image processing techniques are proposed, using tools as contour detection, morphological operations and statistical analysis. Conclusions: the method has an acceptable effectiveness for the context and depends on the characteristics presented by the images.

Effects of cascade reporting of susceptibility profiles for Enterobacterales on broad-spectrum antibiotics use and resistance.

OBJECTIVE: To reduce the inappropriate use of broad-spectrum antibiotics in a 1000+ bed acute tertiary care hospital by the introduction of cascade antimicrobial susceptibility reporting for Enterobacterales. METHODS: Over a 1-year period, we selectively suppressed reporting of susceptibility to the broad-spectrum antibiotics piperacillin-tazobactam (TZP) and meropenem (MEM) for Enterobacterales strains susceptible to amoxicillin-clavulanic acid (AMC) and negative for extended-spectrum ß-lactamase (ESBL). We measured the effects on hospital-wide antibiotic consumption (defined daily doses/1000 admissions) and resistance of Escherichia coli and Klebsiella pneumoniae on two levels. First, we compared resistance and antibiotic use for the antibiotics impacted by the intervention (AMC, TZP and MEM) with control antibiotics that were consistently reported (fluoroquinolones, trimethoprim-sulfamethoxazole and third-generation cephalosporins). Second, we compared the resistance for TZP and MEM with a control pathogen (Pseudomonas aeruginosa) and studied the impact on rate of Clostridioides difficile-associated diarrhoea in our hospital. RESULTS: We observed an overall increased use of AMC relative to overall antibiotic consumption (20.0%, p<0.0001) together with a decreased use of TZP (-11.9%, p=0.049) and unchanged use of MEM (p=0.68) relative to overall antibiotic consumption. As for resistance, the number of ESBL-positive K. pneumoniae strains diminished by 5.9% (p<0.0001). When focusing on intensive care units, the carbapenemase-producing Enterobacterales (CPE) rate also decreased by 4.5% (p=0.0091). For E. coli, no significant difference in ESBL (p=0.33) and CPE (p=0.48) rates were observed. No significant difference in the rate of C. difficile infections was observed (p=0.40). CONCLUSIONS: Restricted susceptibility reporting of TZP and MEM was associated with a significant increased use of AMC and decreased use of TZP relative to overall antibiotic consumption and significant reduction in ESBL- and CPE-positive K. pneumoniae strains.

Faster infection diagnostics for intensive care unit (ICU) patients.

INTRODUCTION: The patient admitted to intensive care units (ICU) is critically ill, to some extent immunosuppressed, with a high risk of infection, sometimes by multidrug-resistant microorganisms. In this context, the intensivist expects from the microbiology service quick and understandable information so that appropriate antimicrobial treatment for that particular patient and infection can be initiated. AREAS COVERED: In this review of recent literature (2015-2021), we identified diagnostic methods for the most prevalent infections in these patients through a search of the databases PubMed, evidence-based medicine online, York University reviewers group, Cochrane, MBE-Trip, and Sumsearch using the terms: adult, clinical laboratory techniques, critical care, early diagnosis, microbiology, molecular diagnostic techniques, spectrometry and metagenomics. EXPERT OPINION: There has been an exponential surge in diagnostic systems used directly on blood and other samples to expedite microbial identification and antimicrobial susceptibility testing of pathogens. Few studies have thus far assessed their clinical impact; final outcomes will also depend on preanalytical and post-analytical factors. Besides, many of the resistance mechanisms cannot yet be detected with molecular techniques, which impairs the prediction of the actual resistance phenotype. Nonetheless, this is an exciting field with much yet to explore.

Qualidade microbiológica do leite humano pasteurizado de um Banco de Leite Paulista / Calidad microbiológica de la leche humana pasteurizada de un banco de leche paulista / Microbiological quality of pasteurized human milk from a Milk Bank of São Paulo

Resumo Objetivo Avaliar a qualidade microbiológica do leite humano pasteurizado proveniente de um Banco de Leite Humano do Estado de São Paulo. Métodos Estudo descritivo conduzido com 29 amostras de leite humano ordenhado pasteurizado (LHOP) obtidas entre julho de 2015 a março de 2016 por meio da avaliação dos registros da acidez titulável bem como da quantificação da microbiota heterotrófica (mesófilos, psicrófilos, termófilos), coliformes totais e termotolerantes, fungos filamentosos e leveduriformes e Staphylococcus spp. Realizou-se a avaliação dos parâmetros físico-químicos por meio do potencial hidrogeniônico-pH, teor energético-K e acidez Dornic-ºD. Análises estatísticas descritivas e bivariadas foram conduzidas. Resultados Evidenciou-se nas amostras a presença de psicrófilos (17,24%), termófilos (27,59%), mesófilos (55,17%), fungos filamentosos e leveduriformes (41,38%) e ausência de Staphylococcus spp. Detectou-se a presença de 82,76% de coliformes no teste presuntivo. Já no teste confirmativo VB constatou-se a presença de 54,16% de coliformes totais e no teste EC 33,33% de coliformes termotolerantes. Os valores de pH e de K não apresentaram oscilações, enquanto que, na expressão da acidez entre 3º a 15°D detectou-se crescimento microbiano. O microrganismo mesófilo, apresentou correlação positiva com variável da acidez Dornic (r=0.44;p=0.01). Conclusão A partir da avaliação da qualidade microbiológica das amostras de LHOP descartado e consideradas impróprias para consumo no referido BLH, especificamente com relação aos indicadores microbiológicos das condições de higiene, sugere que a inviabilidade das amostras possam estar associadas às boas práticas de manipulação do alimento.

Resumen Objetivo Evaluar la calidad microbiológica de la leche humana pasteurizada proveniente de un banco de leche humana del estado de São Paulo. Métodos Estudio descriptivo realizado con 29 muestras de leche humana ordeñada pasteurizada (LHOP) obtenidas entre julio de 2015 y marzo de 2016 por medio de la evaluación de los registros de acidez titulable, así como de la cuantificación de la microbiota heterótrofa (mesófilos, psicrófilos, termófilos), coliformes totales y termotolerantes, hongos filamentosos y levaduriformes y Staphylococcus spp. Se realizó la evaluación de los parámetros físico-químicos mediante el potencial de hidrógeno (pH), valor energético (K) y acidez Dornic-ºD. Se llevaron a cabo análisis descriptivos y bivariados. Resultados Se observó en las muestras la presencia de psicrófilos (17,24 %), termófilos (27,59 %), mesófilos (55,17 %), hongos filamentosos y levaduriformes (41,38 %) y ausencia de Staphylococcus spp. Se detectó la presencia del 82,76 % de coliformes en la prueba presuntiva. Por otro lado, en la prueba confirmativa VB se confirmó la presencia del 54,16 % de coliformes totales, y en la prueba EC se verificó el 33,33 % de coliformes termotolerantes. Los valores de pH y de K no presentaron oscilaciones, mientras que se detectó crecimiento microbiano en la expresión de la acidez entre 3 y 15°D. El microrganismo mesófilo presentó correlación positiva con variable de la acidez Dornic (r=0.44; p=0.01). Conclusión A partir de la evaluación de calidad microbiológica de las muestras de LHOP descartadas y consideradas inapropiadas para consumo en el BLH mencionado, especialmente respecto a los indicadores microbiológicos de las condiciones de higiene, se sugiere que la inviabilidad de las muestras pueda estar asociada con las buenas prácticas de manipulación del alimento.

Abstract Objective To assess the microbiological quality of pasteurized human milk from a Human Milk Bank in the State of São Paulo. Methods This is a descriptive study conducted with 29 pasteurized expressed human milk (PEHM) samples obtained between July 2015 and March 2016 by assessing titratable acidity records as well as quantifying heterotrophic microbiota (mesophiles, psychrophiles, thermophiles), total and thermotolerant coliforms, filamentous and yeast-like fungi and Staphylococcus spp. The physical-chemical parameters were assessed via hydrogen-pH potential, K-energy content and Dornic-ºD acidity. Descriptive and bivariate statistical analyzes were conducted. Results The presence of psychrophiles (17.24%), thermophiles (27.59%), mesophiles (55.17%), filamentous and yeast-like fungi (41.38%) and absence of Staphylococcus spp were evidenced in the sample. The presence of 82.76% of coliforms was detected in the presumptive test. In the confirmatory VB test, the presence of 54.16% of total coliforms was found and, in the EC test, we verified 33.33% of thermotolerant coliforms. The pH and K values did not show oscillations, whereas, in the expression of acidity between 3º and 15°D, microbial growth was detected. The mesophilic microorganism showed a positive correlation with the Dornic acidity variable (r=0.44; p=0.01). Conclusion Based on the microbiological quality assessment of the HMB samples discarded and considered unfit for consumption in the HMB, specifically regarding the microbiological indicators of hygiene conditions, it suggests that the infeasibility of the samples may be associated with good food handling practices.

Establishing the diagnostic stewardship for infectious diseases with multidisciplinary cooperation / 中华检验医学杂志

Many new rapid microbiological diagnostic technologies have been used in clinical setting at present. It is necessary to follow the 5R principles (right patient, right time, right test, right reporting and right interpretation) to establish the diagnostic stewardship system with multidisciplinary cooperation. Diagnostic stewardship will give full play to the advantages of conventional and new technologies, improve clinical practice, save medical cost and curb the development of antimicrobial resistance.

Headspace analyses using multi-capillary column-ion mobility spectrometry allow rapid pathogen differentiation in hospital-acquired pneumonia relevant bacteria.

BACKGROUND: Hospital-acquired pneumonia (HAP) is a common problem in intensive care medicine and the patient outcome depends on the fast beginning of adequate antibiotic therapy. Until today pathogen identification is performed using conventional microbiological methods with turnaround times of at least 24 h for the first results. It was the aim of this study to investigate the potential of headspace analyses detecting bacterial species-specific patterns of volatile organic compounds (VOCs) for the rapid differentiation of HAP-relevant bacteria. METHODS: Eleven HAP-relevant bacteria (Acinetobacter baumanii, Acinetobacter pittii, Citrobacter freundii, Enterobacter cloacae, Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus mirabilis, Staphylococcus aureus, Serratia marcescens) were each grown for 6 hours in Lysogeny Broth and the headspace over the grown cultures was investigated using multi-capillary column-ion mobility spectrometry (MCC-IMS) to detect differences in the VOC composition between the bacteria in the panel. Peak areas with changing signal intensities were statistically analysed, including significance testing using one-way ANOVA or Kruskal-Wallis test (p < 0.05). RESULTS: 30 VOC signals (23 in the positive ion mode and 7 in the negative ion mode of the MCC-IMS) showed statistically significant differences in at least one of the investigated bacteria. The VOC patterns of the bacteria within the HAP panel differed substantially and allowed species differentiation. CONCLUSIONS: MCC-IMS headspace analyses allow differentiation of bacteria within HAP-relevant panel after 6 h of incubation in a complex fluid growth medium. The method has the potential to be developed towards a feasible point-of-care diagnostic tool for pathogen differentiation on HAP.

Low diagnostic yield and time to diagnostic confirmation results in prolonged use of antimicrobials in critically ill children.

Background: Broad-spectrum antimicrobial therapy is a key driver of antimicrobial resistance. Here, we aimed to review indications for antimicrobial therapy, determine the proportion of suspected bacterial infections that are confirmed by culture, and assess the time taken for microbiology test results to become available in the paediatric intensive care unit (PICU). Methods: A single-centre prospective observational cohort study of 100 consecutive general PICU admissions from 30 October 2019 to 19 February 2020. Data were collected from the hospital medical record and entered into a study database prior to statistical analysis using standard methods. Results: Of all episodes of suspected infection, 22% of lower respiratory tract infection, 43% of bloodstream and 0% of central nervous system infection were associated with growth on microbiology culture. 90% of children received antimicrobial therapy. Hospital-acquired infection occurred less commonly than primary infection, but an organism was grown in a greater proportion (64%) of cultures. Final laboratory reports for negative cultures were issued at a median of 120.3 hours for blood cultures and 55.5 hours for endotracheal tube aspirate cultures. Conclusions: Despite most critically children receiving antimicrobial therapy, infection was often not microbiologically confirmed. Novel molecular diagnostics may improve rationalisation of treatment in this population.

The Oral and Gut Bacterial Microbiomes: Similarities, Differences, and Connections.

Background: The oral cavity is associated with local and systemic diseases, although oral samples are not as commonly studied as fecal samples in microbiome research. There is a gap in understanding between the similarities and differences in oral and gut microbiomes and how they may influence each other. Methods: A scoping literature review was conducted comparing oral and gut microbiome communities in healthy humans. Results: Ten manuscripts met inclusion criteria and were examined. The oral microbiome sites demonstrated great variance in differential bacterial abundance and the oral microbiome had higher alpha diversity as compared to the gut microbiome. Studies using 16S rRNA sequencing analysis resulted in overall community differences between the oral and gut microbiomes when beta diversity was analyzed. Shotgun metagenomics sequencing increased taxonomic resolution to strain level (intraspecies) and demonstrated a greater percentage of shared taxonomy and oral bacterial translocation to the gut microbiome community. Discussion: The oral and gut microbiome bacterial communities may be more similar than earlier research has suggested, when species strain is analyzed through shotgun metagenomics sequencing. The association between oral health and systemic diseases has been widely reported but many mechanisms underlying this relationship are unknown. Although future research is needed, the oral microbiome may be a novel interventional target through its downstream effects on the gut microbiome. As nurse scientists are experts in symptom characterization and phenotyping of patients, they are also well posed to lead research on the connection of the oral microbiome to the gut microbiome in health and disease.

PCR coupled to electrospray ionization mass spectrometry for microbiological diagnosis and surveillance of ventilator-associated pneumonia.

Etiological diagnosis is essential for anti-infective therapy in patients with ventilator-associated pneumonia (VAP). The present study aimed to evaluate the capacity of sequential PCR coupled to electrospray ionization mass spectrometry (PCR/ESI-MS) tests as a rapid diagnostic technique for patients with VAP. A total of 12 patients diagnosed with VAP were enrolled at the intensive care unit in Zhongshan Hospital, Fudan University. Mini-bronchoalveolar lavage fluid specimens were prospectively collected on VAP 0, 5 and 10 days following the beginning of mechanical ventilation. Routine clinical culture and PCR/ESI-MS were compared for identification of microorganisms in the specimens. A total of 51 bacterial species were detected by either of the two methods. The positive rates of routine clinical culture and PCR/ESI-MS were 38.2 and 88.2%, respectively. Out of the 16 specimens positive in routine cultures, 15 were also positive on PCR/ESI-MS, except for one, from which a mix of three distinct bacterial isolates were reported by culture. Among the 50 bacterial species identified by PCR/ESI-MS, 15 (35.7%) of the common VAP pathogens were confirmed by paired culture. Furthermore, of the 16 bacterial isolates that were finally confirmed to be responsible for VAP, 14 were identified by a sequential PCR/ESI-MS test concurrently when the culture results were obtained. PCR/ESI-MS identified pathogens that may cause VAP in 8 subjects prior to the occurrence of associated clinical manifestations. To conclude, PCR/ESI-MS was a potential rapid technique for diagnosis of VAP within 6 h. Regular respiratory specimen monitoring using PCR/ESI-MS provides information for selecting appropriate and adequate antibiotic therapies in ventilated patients.

Fast track SSTI management program based on a rapid molecular test (GeneXpert® MRSA/SA SSTI) and antimicrobial stewardship.

PURPOSE: This study examines the impacts of a skin and soft tissue infection (SSTI) management program involving a rapid diagnostic algorithm (Gram stain plus real-time PCR, GeneXpert® MRSA/SA SSTI) performed directly on clinical samples plus antimicrobial stewardship (AMS) counseling of the responsible physician. METHODS: Participants were 155 consecutive adult inpatients with SSTI and good quality clinical samples submitted to the microbiology laboratory from April 2016 to January 2017. Results of the rapid test and AMS recommendations were phoned through to the responsible physician. The comparison group was a historical cohort. RESULTS: Most SSTI were surgical wound infections (41.3% vs 38.1% for the intervention and comparison groups respectively) followed by diabetic foot (14.2% and 18.1%), abscesses (13.5% both) and cellulitis (12.9% both). Isolated microorganisms were mostly Gram-negative bacilli (two-thirds), followed by Staphylococcus aureus (SA). The ratio methicillin-susceptible SA (MSSA) to methicillin-resistant SA (MRSA) was 4:1. Improvements in the intervention cohort were: DOT (22.0 vs. 24.3 days, p = 0.007), treatment duration per SSTI episode (14.1 vs. 15.0 days, p = 0.072), treatment cost (433.1 vs. 533.3 €, p = 0.039), length of stay (18.6 vs 20.7 days, p = 0.031), related mortality (1 vs. 4 patients, p = 0.022) and Clostridium difficile infection (CDI) (4 vs. 8 patients, p = 0.050). In 48 cases (31.4%) in the intervention group, advice was given to improve empiric antibiotic treatment. CONCLUSION: This type of program could help adjust antibiotic treatment when inappropriate, reducing antibiotic use and costs, length of stay, CDI and related mortality.

Research advances in fecal microbiota transplantation for the treatment of HBeAg-positive chronic hepatitis B / 临床肝胆病杂志

HBeAg seroconversion is an important process during antiviral therapy for patients with HBeAg-positive chronic hepatitis B (CHB), while the first-line antiviral drugs, such as entecavir and tenofovir disoproxil fumarate, tend to have low HBeAg clearance rate and/or seroconversion rate, and at present, there is still a lack of effective radical treatment regimens. Latest studies have shown that fecal microbial transplantation (FMT) can induce HBeAg clearance in HBeAg-positive CHB patients receiving long-term antiviral therapy. This article reviews the research advances in the role of FMT in inducing HBeAg clearance in HBeAg-positive CHB patients and points out that FMT may become a new treatment regimen for HBeAg-positive CHB patients.

Effect of Listerine Mouthwash with Green Tea on the Inhibition of Streptococcus Mutans: A Microbiologic Study

Abstract Objective: To evaluate in vitro the antimicrobial effect of Listerine-green tea mouthwash on Streptococcus mutans (SM) in comparison with 0.12% Chlorhexidine (CHX) and Listerine-Zero. Material and Methods: The sensitivity and growth inhibition of SM bacterial species were evaluated and compared between Listerine-green tea, 0.12% CHX and Listerine-Zero mouthwashes. Sixty plates containing SM colonies were prepared in three groups (n=20), and growth inhibition zones were measured using the disk diffusion agar test in mm. Data were analyzed with SPSS 21. One-way ANOVA was used to compare the efficacy of the three mouthwashes tested. Post hoc Tukey tests were used for two-by-two comparisons. Statistical significance was defined at P<0.05. Results: Analysis of data showed significant differences between the three groups (p<0.001); 0.12% CHX was the most effective mouthwash, and Listerine-Zero exhibited the least effect on the growth inhibition of SM (p<0.004). Conclusion: All three mouthwashes were significantly effective in inhibiting the growth of SM. The effect of Listerine-green tea mouthwash was higher than that of Listerine-Zero and less than that of 0.12% CHX.

Análise microbiológica de escovas de dente usadas por adultos do município de Sumaré-SP / Muicrobiological analysis of toothbrushes used by adults of Sumaré-SP

Objetivo ­ Realizar análise microbiológica de escovas dentais utilizadas por moradores da cidade de Sumaré e ainda analisar seus hábitos de higiene e cuidados com a escova de dente. Métodos ­ Foram selecionados 100 voluntários aleatoriamente, com idade a partir de 18 anos para responder um questionário sobre hábitos de higiene e cuidados com as suas escovas dentais e desses voluntários 20 escovas foram coletadas de forma aleatória para análise microbiológica e de desgaste das cerdas, no laboratório de análises clínicas da Universidade Paulista. Resultados ­ Verificou-se que a maioria (56%) escovam os dentes duas vezes ao dia, que 44% (44/100) trocam as escovas no período de 2 a 3 meses, porém a maior parte não apresentava conhecimento em relação aos métodos de desinfecção para escova de dentes. Com relação a análise de desgastes das cerdas, 50% apresentavam a maioria dos tufos das cerdas divergentes, com tufos cobrindo outros tufos. Quanto a análise microbiológica 85% (17/20) das escovas de dentes apresentou crescimento microbiano, no qual a maior parte (75%) compreendia em Staphylococcus spp., seguido por 30% de enterobactérias, 5% de bacilo gram-positivo,15% Streptococcus spp. e 10% diplococos gram-negativo. Conclusão ­ Nesta perspectiva percebe-se que existe uma necessidade de conscientizar a população em relação à manutenção adequada das escovas de dentes. Quanto a contaminação nas escovas, observamos que não está necessariamente relacionada ao tempo de uso e desgaste das cerdas da escova dental.

Objective ­ The objective of this study is to verify the presence of bacteria in the toothbrush and to evaluate the knowledge of the residents of the Sumaré city about toothbrush care. Methods ­ Were selected 100 volunteers randomly, aged 18 years and older to answer a questionnaire, and of theses 20 brushes were randomly collected for microbiological and bristle wear analyzes in the toothbrush at the clinical analyzes laboratory of Universidade Paulista. Results ­ Most (56%) brush their teeth twice a day, 44% (44/100) changes their brushes within 2 to 3 months, but most respondents do not know disinfection methods for toothbrush. In relation the toothbrush bristle wear analysis, 50% presented the majority of divergent bristle, with tufts, covering other tufts. Regarding the microbiological analysis, 85% (17/20) of the toothbrushes showed a microbial growth, where the most (75%) comprised of Staphylococcus spp., followed by 30% enterobacteria, 5% bacilli gram positive, 15% Streptococcus spp. and 10% diplococci gram negative. Conclusion ­ In this perspective, it is observed that there is a need to make the population aware of the maintenance of toothbrushes. About contamination in the brushes, we observed that not necessarily it is associate to time of use and wear of toothbrush bristles.

HIRA-TAN detects pathogens of pneumonia with a progressive course despite antibiotic treatment.

BACKGROUND: Empiric antibiotics are administered for pneumonia when the causative pathogens are unidentified. Pathogen-directed therapy is impeded by negative culture results and/or culture time lag. This circumstance necessitates a salvage method for pathogen identification, especially when antibiotic therapy has failed. Here, we aimed to preliminarily investigate the HIRA-TAN method in pneumonia with a progressive course despite prior empiric antibiotic therapy. METHODS: This prospective study was conducted for patients who were referred to Dr. Zainoel Abidin Hospital, Aceh, Indonesia, from December 2016 to January 2017, owing to pneumonia with a progressive course. Sputum or pleural effusion was subjected to culture and the HIRA-TAN assay. The HIRA-TAN identified the candidate causative pathogens based on the difference in the cycle threshold (Ct) between the targeted pathogen and the single-copy human gene. RESULTS: Patients (n=27) were predominantly males (22 patients, 81.5%), with a median age of 62 years. All patients had comorbid disease and were classified as hospital-acquired pneumonia (25 patients, 92.6%) with multilobar infiltrates (22 patients, 81.5%). Bacterial culture identified causative pathogen(s) in some (14 patients, 51.8%), whereas the HIRA-TAN identified pathogen(s) in most (23 patients, 85.2%). The rapid pathogen identification by the HIRA-TAN will provide valuable information in guiding pathogen-directed therapy. CONCLUSIONS: The result warrants a larger clinical trial to confirm the clinical efficacy of the HIRA-TAN in patients with progressive pneumonia despite previous antibiotic treatment.