Ultra-Sensitive Droplet Digital PCR for the Assessment of Microchimerism in Cellular Therapies.

Current techniques to assess chimerism after hematopoietic stem cell transplantation (HSCT) are limited in both sensitivity and precision. These drawbacks are problematic in the context of cellular therapies that frequently result in microchimerism (donor chimerism <1%). We have developed a highly sensitive droplet digital PCR (ddPCR) assay using commercially available regents with good performance throughout the range of clinically relevant chimerism measurements, including microchimerism. We tested the assay using spiked samples of known donor-recipient ratios and in clinical samples from HSCT recipients and patients enrolled on clinical trials of microtransplantation and third-party virus-specific T cells (VSTs). The levels of detection and quantification of the assay were .008% and .023%, with high levels of precision with samples of DNA content ranging from 1 to 300 ng DNA. From the panel of 29 insertion-deletion probes multiple informative markers were found for each of 43 HSCT donor-recipient pairs. In the case of third-party cellular therapies in which there were 3 DNA contributors (recipient, HSCT donor, and T-cell donor), a marker to detect the cellular product in a background of recipient and donor cells was available for 11 of 12 cases (92%). Chimerism by ddPCR was able to quantify chimerism in HSCT recipients and comparison against standard STR analysis in 8 HSCT patients demonstrated similar results, with the advantage of fast turnaround time. Persistence of donor microchimerism in patients undergoing microtransplantation for acute myeloid leukemia was detectable for up to 57 days in peripheral blood and bone marrow. The presence of microtransplant product DNA in bone marrow T cells after cell sorting was seen in the 1 patient tested. In patients receiving third-party VSTs for treatment of refractory viral infections, VST donor DNA was detected at low levels in 7 of 9 cases. ddPCR offers advantages over currently available methods for assessment of chimerism in standard HSCT and cellular therapies.

Prospects for adoptive T-cell therapy for invasive fungal disease.

PURPOSE OF REVIEW: Invasive fungal disease (IFD) is a cause of morbidity and mortality in allogeneic hematopoietic stem cell transplant (HSCT) recipients. As more potent broad-spectrum antifungal agents are used in prophylaxis, drug resistance and less common fungal species have increased in frequency. Here we review current treatments available for IFD and examine the potential for adoptive T-cell treatment to enhance current therapeutic choices in IFD. RECENT FINDINGS: There is growing evidence supporting the role of T cells as well as phagocytes in antifungal immunity. T cells recognizing specific antigens expressed on fungal morphotypes have been identified and the role of T-cell transfer has been explored in animal models. The clinical efficacy of adoptive transfer of antigen-specific T cells for prophylaxis and treatment of viral infections post-HSCT has raised interest in developing good manufacturing practice (GMP)-compliant methods for manufacturing and testing fungus-specific T cells after HSCT. SUMMARY: As the outcomes of IFD post-HSCT are poor, reconstitution of antifungal immunity offers a way to correct the underlying deficiency that has caused the infection rather than simply pharmacologically suppress fungal growth. The clinical development of fungus specific T cells is in its early stages and clinical trials are needed in order to evaluate safety and efficacy.

Hitchhiking to the abyss.

We investigated, for the first time, the hitchhiker-host fidelity of deep-diving whale sharks and Chilean devil rays. We found that two of the most ubiquitous oceanic hitchhikers, the common remora and the pilot fish, are able to follow their hosts to bathypelagic depths, where they are exposed to extreme gradients of light, dissolved oxygen, temperature, and pressure. We documented a deep dive of a large whale shark hosting remoras and pilot fish. Common remora was observed at the deepest section of the dive, at 1460 m, where the water temperature was 3.6°C. A pilot fish was recorded at 900 m, during the ascent phase, with the water temperature of 7.5°C. Although the adaptations that allow these hitchhikers to mitigate the impacts of such extreme environmental conditions remain unknown, we discuss these findings in the framework of the ecophysiology of deep diving and the hitchhiker-host fidelity.

Neuroprotective effect of natural products against Alzheimer's disease.

Nature has gifted mankind with a plethora of flora-bearing fruits, vegetables and nuts. The diverse array of bioactive nutrients present in these natural products plays a pivotal role in prevention and cure of various neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease and other neuronal dysfunctions. Accumulated evidence suggests that naturally occurring phyto-compounds, such as polyphenolic antioxidants found in fruits, vegetables, herbs and nuts, may potentially hinder neurodegeneration, and improve memory and cognitive function. Nuts such as walnut have also demonstrated neuroprotective effect against AD. The molecular mechanisms behind the curative effects rely mainly on the action of phytonutrients on distinct signalling pathways associated with protein folding and neuroinflammation. The neuroprotective effects of various naturally occurring compounds in AD is evaluating in this review.

Recent rodent models for Alzheimer's disease: clinical implications and basic research.

Alzheimer's disease (AD) is the most common origin of dementia in the elderly. Although the cause of AD remains unknown, several factors have been identified that appear to play a critical role in the development of this debilitating disorder. In particular, amyloid precursor protein (APP), tau hyperphosphorylation, and the secretase enzymes, have become the focal point of recent research. Over the last two decades, several transgenic and non-transgenic animal models have been developed to elucidate the mechanistic aspects of AD and to validate potential therapeutic targets. Transgenic rodent models over-expressing human ß-amyloid precursor protein (ß-APP) and mutant forms of tau have become precious tools to study and understand the pathogenesis of AD at the molecular, cellular and behavioural levels, and to test new therapeutic agents. Nevertheless, none of the transgenic models of AD recapitulate fully all of the pathological features of the disease. Octodon degu, a South American rodent has been recently found to spontaneously develop neuropathological signs of AD in old age. This review aims to address the limitations and clinical relevance of transgenic rodent models in AD, and to highlight the potential for O. degu as a natural model for the study of AD neuropathology.

Rapidly expanded partially HLA DRB1-matched fungus-specific T cells mediate in vitro and in vivo antifungal activity.

Invasive fungal infections are a major cause of disease and death in immunocompromised hosts, including patients undergoing allogeneic hematopoietic stem cell transplant (HSCT). Recovery of adaptive immunity after HSCT correlates strongly with recovery from fungal infection. Using initial selection of lymphocytes expressing the activation marker CD137 after fungal stimulation, we rapidly expanded a population of mainly CD4+ T cells with potent antifungal characteristics, including production of tumor necrosis factor α, interferon γ, interleukin-17, and granulocyte-macrophage colony stimulating factor. Cells were manufactured using a fully good manufacturing practice-compliant process. In vitro, the T cells responded to fungal antigens presented on fully and partially HLA-DRB1 antigen-matched presenting cells, including when the single common DRB1 antigen was allelically mismatched. Administration of antifungal T cells lead to reduction in the severity of pulmonary and cerebral infection in an experimental mouse model of Aspergillus. These data support the establishment of a bank of cryopreserved fungus-specific T cells using normal donors with common HLA DRB1 molecules and testing of partially HLA-matched third-party donor fungus-specific T cells as a potential therapeutic in patients with invasive fungal infection after HSCT.

[Molecular and phenotypical typification of methicillin resistant Staphylococcus aureus (MRSA) strains in a university hospital]. / Tipificación molecular y fenotípica de Staphylococcus aureus resistentes a meticilina (SAMR) en un hospital universitario.

OBJECTIVE: To typify by molecular and phenotypical methods, MRSA strains, isolated from patients and nurses to establish their possible clonal origin. MATERIALS AND METHODS: 50 MRSA strains isolated in a teaching hospital in Maracaibo (Venezuela) were analyzed. The typification of MRSA strains was performed by means of pulsed-field gel electrophoresis (PFGE) and antibiotyping. RESULTS: In patients, 12 clusters (I-XII) and 19 antibiotypes were found; whereas in the health-care personnel, 6 clusters (I-VI) and two antbiotypes were detected. There was no statistically significative association between antibiotypes and band patterns obtained by PFGE (p>0.05). CONCLUSIONS: By means of detection of resistance markers and PFGE, it is feasible to discrimínate the nature of the clinical strains of MRSA. The obtained results show the possible nosocomial transmission of MRSA strains and their clonal spread in hospital departments, particularly at the ICU.

Kynurenine 3-Monooxygenase Activity in Human Primary Neurons and Effect on Cellular Bioenergetics Identifies New Neurotoxic Mechanisms.

Upregulation of the kynurenine pathway (KP) of tryptophan metabolism is commonly observed in neurodegenerative disease. When activated, L-kynurenine (KYN) increases in the periphery and central nervous system where it is further metabolised to other neuroactive metabolites including 3-hydroxykynurenine (3-HK), kynurenic acid (KYNA) and quinolinic acid (QUIN). Particularly biologically relevant metabolites are 3-HK and QUIN, formed downstream of the enzyme kynurenine 3-monooxygenase (KMO) which plays a pivotal role in maintaining KP homeostasis. Indeed, excessive production of 3-HK and QUIN has been described in neurodegenerative disease including Alzheimer's disease and Huntington's disease. In this study, we characterise KMO activity in human primary neurons and identified new mechanisms by which KMO activation mediates neurotoxicity. We show that while transient activation of the KP promotes synthesis of the essential co-enzyme nicotinamide adenine dinucleotide (NAD+), allowing cells to meet short-term increased energy demands, chronic KMO activation induces production of reactive oxygen species (ROS), mitochondrial damage and decreases spare-respiratory capacity (SRC). We further found that these events generate a vicious-cycle, as mitochondrial dysfunction further shunts the KP towards the KMO branch of the KP to presumably enhance QUIN production. These mechanisms may be especially relevant in neurodegenerative disease as neurons are highly sensitive to oxidative stress and mitochondrial impairment.

[Vaginal colonization by genital mycoplasmas in pregnant and non-pregnant women]. / Colonización vaginal por micoplasmas genitales en mujeres embarazadas y no embarazadas.

To compare vaginal colonization by genital micoplasmas in pregnant and non pregnant women and to determine the association between pregnancy and colonization by these microorganisms, samples of exocervix an endocervix from pregnant (n = 80) and non pregnant (n = 65) women, from two health centers of Maracaibo, Zulia State, Venezuela were processed. The Mycoplasma-Lyo kit (bioMérieux laboratories) was used for the culture and identification of genital micoplasmas. In pregnant women, prevalences of 10% for M. hominis and 26.25% for Ureaplasma spp. were found; 35.38% for M. hominis and 20% for Ureaplasma spp. in non-pregnant, were obtained. Among the pregnant, Ureaplasma spp. was the most frequently isolated micoplasma, in symptomatic and asymptomatic; while in the non pregnant group, M. hominis was more common among the symptomatic patients; only one case (1.54%) was an asymptomatic carrier of Ureaplasma spp. The highest positivity percentages were obtained in primigravidas (48.71%) and during the second gestational trimester (34.21%). No statistically significant differences were found between vaginal colonization by genital micoplasmas according to age, number of pregnancy and gestational trimester; but they were found between the presented symptomatology and vaginal colonization by genital micoplasmas. Genital micoplasmas were isolated from gravid women at approximately the same recovery rate as in non-pregnant women; being M. hominis the most frequently isolated in non-pregnant women and Ureaplasma spp. in the pregnant group.

Major Developments in the Design of Inhibitors along the Kynurenine Pathway.

Disrupted kynurenine pathway (KP) metabolism has been implicated in the progression of neurodegenerative disease, psychiatric disorders and cancer. Modulation of enzyme activity along this pathway may therefore offer potential new therapeutic strategies for these conditions. Considering their prominent positions in the KP, the enzymes indoleamine 2,3-dioxygenase, kynurenine 3-monooxygenase and kynurenine aminotransferase, appear the most attractive targets. Already, increasing interest in this pathway has led to the identification of a number of potent and selective enzyme inhibitors with promising pre-clinical data and the elucidation of several enzyme crystal structures provides scope to rationalize the molecular mechanisms of inhibitor activity. The field seems poised to yield one or more inhibitors that should find clinical utility.

Epigallocatechin-3-gallate induces oxidative phosphorylation by activating cytochrome c oxidase in human cultured neurons and astrocytes.

Mitochondrial dysfunction and resulting energy impairment have been identified as features of many neurodegenerative diseases. Whether this energy impairment is the cause of the disease or the consequence of preceding impairment(s) is still under discussion, however a recovery of cellular bioenergetics would plausibly prevent or improve the pathology. In this study, we screened different natural molecules for their ability to increase intracellular adenine triphosphate purine (ATP). Among them, epigallocatechin-3-gallate (EGCG), a polyphenol from green tea, presented the most striking results. We found that it increases ATP production in both human cultured astrocytes and neurons with different kinetic parameters and without toxicity. Specifically, we showed that oxidative phosphorylation in human cultured astrocytes and neurons increased at the level of the routine respiration on the cells pre-treated with the natural molecule. Furthermore, EGCG-induced ATP production was only blocked by sodium azide (NaN3) and oligomycin, inhibitors of cytochrome c oxidase (CcO; complex IV) and ATP synthase (complex V) respectively. These findings suggest that the EGCG modulates CcO activity, as confirmed by its enzymatic activity. CcO is known to be regulated differently in neurons and astrocytes. Accordingly, EGCG treatment is acting differently on the kinetic parameters of the two cell types. To our knowledge, this is the first study showing that EGCG promotes CcO activity in human cultured neurons and astrocytes. Considering that CcO dysfunction has been reported in patients having neurodegenerative diseases such as Alzheimer's disease (AD), we therefore suggest that EGCG could restore mitochondrial function and prevent subsequent loss of synaptic function.

Perfiles de resistencia a fluoroquinolonas en cocos Gram positivos de importancia clínica / Fluoroquinolone's resistance profiles in Gram-positive cocci of clinical importance

Para evaluar la resistencia a fluoroquinolonas en aislamientos clínicos de cocos grampositivos se revisaron los resultados de los cultivos procesados en el Centro de Referencia Bacteriológica del Servicio Autónomo Hospital Universitario de Maracaibo, durante el periodo enero 2011-diciembre 2015. Los datos fueron analizados mediante el software WHONETTM, (versión 5,6) y el IBM® SPSS® Statistics para Windows, (versión 25). Se encontró una frecuencia de 29,70% para los cocos grampositivos (9.292 cepas), correspondiendo el 76,18% de los aislamientos al género Staphylococcus (7.072); 15,30% a Enterococcus (1.422) y 8,59% a Streptococcus (798). Para Staphylococcus, la resistencia fue mayor en cepas resistentes a meticilina. Las tasas de resistencia más elevadas se detectaron en los enterococos, especialmente en Enterococcus faecium resistente a vancomicina. No se detectó resistencia a fluoroquinolonas en las cepas de Enterococcus faecalis resistentes a vancomicina. Los estreptococos, incluyendo Streptococcus pneumoniae, se mostraron, mayormente, sensibles a las fluoroquinolonas. La mayoría de las cepas de estafilococos y enterococos; presentó, resistencia cruzada a todas las fluoroquinolonas probadas. La distribución de la resistencia a las fluoroquinolonas por año de estudio en cada género bacteriano fue diferente. La resistencia a las fluoroquinolonas muestra una tendencia creciente en los tres géneros de cocos grampositivos evaluados

To evaluate the resistance to fluoroquinolones in clinical isolates of Gram-positive cocci records of processed culture al the Bacteriological Reference Center of the Autonomous Service University Hospital of Maracaibo during the period January 2011-December 2015, were reviewed. The data was analyzed using WHONETTM software (version 5.6) and IBM® SPSS® Statistics for Windows (version 25). A frequency of 29.70% was found for Gram-positive cocci (9,292 strains), with 76.18% of isolates corresponding to the genus Staphylococcus (7,072); 15.30% to Enterococcus (1422) and 8.59% to Streptococcus (798). For Staphylococcus, resistance was higher in methicillin-resistant strains. The highest resistance rates were detected in enterococci, especially vancomycin-resistant Enterococcus faecium. No resistance to fluoroquinolones was detected in vancomycin-resistant Enterococcus faecalis strains. Streptococci, including Streptococcus pneumoniae, were mostly sensitive to fluoroquinolones. Most strains of staphylococci and enterococci; presented cross resistance to all tested fluoroquinolones. The distribution of resistance to fluoroquinolones per year of study in each bacterial genus was different. Resistance to fluoroquinolones shows an increasing trend in the three genera of Gram-positive cocci evaluated

Susceptibilidad a meticilina y vancomicina en Staphylococcus aureus aislados de hemocultivos / Susceptibility to methicillin and vancomycin in Staphylococcus aureus isolated from blood cultures

Para determinar la susceptibilidad a meticilina y vancomicina en cepas de Staphylococcus aureus aisladas de hemocultivos, se analizaron los registros de pacientes ingresados en las Unidades de Cuidados Intensivos del Servicio Autónomo Hospital Universitario de Maracaibo durante el período enero 2011-diciembre 2015. Se procesaron 35.341 hemocultivos; 5.072 (14,35%) fueron positivos; en 455 (8,97%) se aislaron 96 cepas de Staphylococcus aureus (21,09%), de las cuales, 78 (81,25%) fueron resistentes y 18 (18,75%), sensibles a meticilina. Todos los aislados resultaron sensibles a vancomicina. El 61,45% de las cepas expresó multirresistencia. No se encontró diferencia estadísticamente significativa en la frecuencia de aislamiento de Staphylococcus aureus por año, edad y sexo del paciente (p > 0,05); pero si según el tipo de unidad y la presencia de co-resistencia antimicrobiana (p < 0,05). Los elevados niveles de resistencia a meticilina y la evidencia de fenotipos sensibles a vancomicina con valores elevados de concentración inhibitoria mínima (> 1 µg/ml), demandan la vigilancia sistemática del patrón de susceptibilidad antimicrobiana a fin de guiar a los clínicos para elegir la terapia empírica adecuada, contribuyendo al reforzamiento continuo de las precauciones estándar y al establecimiento de las políticas locales de administración y regulación del uso de antimicrobianos

To determine susceptibility to methicillin and vancomycin in blood-isolated strains of Staphylococcus aureus isolated from blood cultures, patient records entered in the Intensive Care Units of the Autonomous Hospital University Service of Maracaibo were analyzed during the period January 2011-December 2015. 35,341 blood cultures were processed; 5.072 (14,35%) were positive; in 455 (8.97%)96 strains of Staphylococcus aureus (21.09%) were isolated, of which 78 (81.25%) were resistant and 18 (18.75%), sensitive to methicillin. All isolates were sensitive to vancomycin. 61.45% of the strains expressed multi-resistance. No statistically significant difference in the frequency of isolation of Staphylococcus aureus per year, age and sex of the patient (p > 0.05) was found; but if according to the type of unit and the presence of antimicrobial co-resistance (p ˂ 0.05). The high levels of methicillin resistance and the evidence of vancomycin-sensitive phenotypes with high minimum inhibitory concentration values (>1 µg/ml), require systematic monitoring of the antimicrobial susceptibility pattern in order to guide clinicians to choose appropriate empirical therapy, contributing to the continuous strengthening of standard precautions and the establishment of local policies for the administration and regulation of the use of antimicrobials

Etiología de la diarrea infantil en Shushufindi, Ecuador / Etiology of the child diarrhea in Shushufindi, Ecuador

La diarrea infecciosa es un importante problema de salud mundial; sin embargo, poco se sabe sobre su etiología en la ciudad de Shushufindi, Ecuador. El objetivo de esta investigación fue determinar la etiología de la diarrea infecciosa en niños. Se recolectaron 154 muestras fecales provenientes de niños de ambos sexos que acudieron al laboratorio de un centro de salud durante el periodo enero-marzo 2018. Se realizó coprocultivo, examen parasitológico directo e inmunoensayo cromatográfico. En 124 muestras (80,52%) se detectó la presencia de organismos enteropatógenos, de las cuales 74 (59,68%) fueron positivas para bacterias; 36 (29,03%) para parásitos y 14 (11,29%) para rotavirus. Los organismos aislados fueron: 35 (28,23%) Salmonella sp.; 26 (20,97%) Shigella sp.; 13 (10,48%) Campylobacter sp.; 15 (12,10%) G. intestinalis; 10 (8,06%) T. trichiura; 5 (4,03%) E. histolytica/dispar/moshkovskii; 3 (2,42%) A. lumbricoides; S. stercoralis y rotavirus14 (11,29%), cada uno. Se encontró asociación estadísticamente significativa entre la presencia de parásitos y la edad y sexo del paciente; así como también entre la presencia de bacterias y la edad de los niños. Este estudio demuestra la participación de un pequeño grupo de patógenos como los principales agentes causales de la diarrea infecciosa en la población infantil estudiada.

Infectious diarrhea is a major global health problem; however, little is known about its etiology in the city of Shushufindi, Ecuador. The objective of this investigation was to determine the etiology of infectious diarrhea in children. 154 fecal samples were collected from children of both sexes who attended the laboratory of a health center during the period January-March 2018. Stool culture, direct parasitological examination and immunochromatographic assay were performed. In 124 samples (80.52%) the presence of enteropathogenic organisms was detected, of which 74 (59.68%) were positive for bacteria; 36 (29.03%) for parasites and 14 (11.29%) for rotavirus. The isolated organisms were: 35 (28.23%) Salmonella spp.; 26 (20.97%) Shigella spp.; 13 (10.48%) Campylobacter spp.; 15 (12.10%) G. intestinalis; 10 (8.06%) T. trichiura; 5 (4.03%) E. histolytica/dispar/moshkovskii; 3 (2.42%) A. lumbricoides; S. stercoralis and rotavirus 14 (11.29%), each one. A statistically significant association was found between the presence of parasites and the age and sex of the patient; as well as between the presence of bacteria and the age of children. This study demonstrates the participation of a small group of pathogens as the main causative agents of infectious diarrhea in the child population studied.

Calidad microbiológica del agua subterránea como riesgo epidemiológico en la producción de enfermedad diarreica infantil. Revisión Sistemática / Microbiological quality of groundwater as an epidemiological risk in the production of Childhood Diarrheal Disease. Systematic review

El agua de consumo humano y su calidad son determinantes para la salud pública. Esta revisión pretende recopilar y analizar información acerca de la relación entre la enfermedad diarreica en niños menores de cinco (5) años y la contaminación de las fuentes de agua subterránea. Se consultaron las bases: PubMed, ScienceDirect, SpringerLink, SciELO y Google Scholar, sin limitación en fechas de publicación; utilizando los descriptores: agua subterránea, diarrea, enfermedad gastrointestinal infantil, contaminación microbiana, calidad del agua, diarrea infantil, agua potable, técnicas moleculares y técnicas bioquímicas, analizándose un total de ciento sesenta y nueve (169) publicaciones. Se encontró relación entre la contaminación microbiana del agua subterránea y la diarrea infantil. El agua subterránea se contamina debido a fugas de fosas sépticas, métodos inadecuados de manejo de desechos y escorrentías de agua de lluvia, determinando la prevalencia de diarrea infantil. De allí, la importancia de monitorear la calidad del agua como factor de riesgo, con la detección y cuantificación de bioindicadores, mediante métodos rutinarios y novedosos, e incorporar intervenciones dirigidas a mejorar la accesibilidad a fuentes de agua controladas y la educación sanitaria en la búsqueda de asegurar la protección del agua y la disminución en la prevalencia de la diarrea infantil. Esta revisión está registrada en PROSPERO bajo el número ID 129254

Water for human consumption and its quality are determinants for public health. This review aims to collect and analyze information about the relationship between diarrheal disease in children under five (5) years of age and contamination of groundwater sources. The bases: PubMed, ScienceDirect, SpringerLink, SciELO and Google Scholar, without limitation on publication dates, using the descriptors: groundwater, diarrhea, childhood gastrointestinal disease, microbial contamination, water quality, childhood diarrhea, drinking water, molecular techniques and biochemical techniques, were consulted, analyzing a total of one hundred sixty-nine (169) publications. A relationship was found between microbial contamination of groundwater and childhood diarrhea. Groundwater is contaminated due to septic tank leaks, inadequate methods of waste management and rainwater runoff, determining the prevalence of childhood diarrhea. From there, the importance of monitoring water quality as a risk factor, with the detection and quantification of bioindicators, through routine and novel methods, and incorporating interventions aimed at improving accessibility to controlled water sources and health education in the search to ensure water protection and the decrease in the prevalence of childhood diarrhea. This revision is registered in PROSPERO under the number ID 129254.

Infección urinaria en pacientes con diabetes mellitus tipo 2: frecuencia, etiología, susceptibilidad antimicrobiana y factores de riesgo / Urinary infection in patients with type 2 diabetes mellitus: frequency, etiology, antimicrobial susceptibility and risk factors

Las infecciones urinarias son comunes en pacientes diabéticos. El objetivo de esta investigación fue: determinar la frecuencia, etiología, susceptibilidad antimicrobiana y factores de riesgo asociados a infección urinaria en pacientes con diabetes tipo 2. Se estudiaron 108 pacientes ambulatorios, con diagnóstico presuntivo de infección de vías urinarias, durante el periodo mayo 2016 - mayo 2017, en la ciudad de Jipijapa, Ecuador. Para el urocultivo se utilizó la técnica del asa calibrada. La susceptibilidad a los antibióticos se determinó mediante el método de Kirby & Bauer. Las variables cualitativas se compararon con ji cuadrado o la prueba exacta de Fisher. Se calculó el Odd radio (OR) y sus intervalos de confianza (IC) del 95%. Valores de p ≤ 0,05 fueron considerados significativos. La frecuencia de infección urinaria fue de 73,15%. El microorganismo más frecuentemente aislado fue Escherichia coli (78,48%). Los mayores porcentajes de resistencia se observaron para amoxicilina (78,87%) y cefalexina (71,83%). Los malos hábitos de higiene, la presencia de cálculos renales y una vida sexual activa resultaron factores de riesgo para las infecciones urinarias. La nitrofurantoina, fosfomicina, fluoroquinolonas y algunos betalactámicos, todavía representan una alternativa de utilidad en la quimioterapia de las infecciones urinarias no complicadas en pacientes diabéticos.

Urinary infection is common in diabetic patients. The objective of this research was to determine the frequency, etiology, antimicrobial susceptibility and risk factors associated with urinary tract infection in patients with type 2 diabetes. 108 outpatients with a presumptive diagnosis of urinary tract infection during May 2016-May 2017, in the city of Jipijapa, Ecuador, were studied. For the uroculture the calibrated loop technique was used. The susceptibility to antibiotics was determined by the Kirby & Bauer method. The qualitative variables were compared with chi-squared or Fisher's exact test. The Odd radio (OR) and its 95% confidence intervals (CI) were calculated. Values of p ≤ 0.05 were considered significant. A frequency of 73.15% of urinary infection was found. The microorganism most frequently isolated was Escherichia coli (78.48%). The highest percentages of resistance were observed for amoxicillin (78.87%) and cephalexin (71.83%). Bad hygiene habits, the presence of kidney stones and an active sex life were risk factors for urinary tract infections. Nitrofurantoin, fosfomycin, fluoroquinolones and some beta-lactams still represent a useful alternative in the chemotherapy of uncomplicated urinary tract infections in diabetic patients.

Frecuencia y resistencia antimicrobiana en Staphylococcus / Frequency and antimicrobial resistance in Staphylococcus

La presente investigación tuvo como objetivo establecer la frecuencia de aislamiento de las diferentes especies de estafilococos y determinar la resistencia antimicrobiana de las cepas aisladas. Se realizó un estudio retrospectivo, en cepas aisladas en el Centro de Referencia Bacteriológica del Servicio Autónomo Hospital Universitario de Maracaibo, durante el período enero 2011 ­ diciembre 2015. Se obtuvo un porcentaje de aislamiento para S. aureus del 61,36% y 38,64% para coagulasa negativa, observándose mayor frecuencia de aislamiento en el área de hospitalización para ambos grupos de microorganismos. Las muestras de piel y tejidos blandos representaron las principales fuentes de aislamiento para S. aureus; mientras que para el grupo coagulasa negativa, fueron las muestras de sangre. Todas las cepas fueron sensibles a los glicopéptidos. La resistencia para los b-lactámicos fue acentuada para ambos grupos bacterianos, mostrando variabilidad para macrólidos y lincosamidas y para los restantes antibióticos probados, se encontraron bajos porcentajes de resistencia. Los resultados demuestran que S. aureus es la especie más frecuente del género; seguida de S. epidermidis y S. haemolyticus entre coagulasa negativa. Ambos grupos de microorganismos expresan fenotipos de resistencia a penicilina y eritromicina, sensibilidad a vancomicina y teicoplanina y susceptibilidad variable al resto de antibióticos evaluados.

The objective of the present investigation was to establish the frequency of isolation of the different species of staphylococci and to determine the antimicrobial resistance of the isolated strains. A retrospective study was carried out in isolated strains at the Bacteriological Reference Center of the Autonomous Service of the University Hospital of Maracaibo during the period January 2011 to December 2015. A percentage of isolation was obtained for S. aureus of 61.36% and 38,64% for coagulase negative, showing a higher frequency of isolation in the hospitalization area for both groups of microorganisms. Skin and soft tissue samples represented the main sources of isolation for S. aureus; while for the coagulase negative group, they were blood samples. All strains were sensitive to glycopeptides. Resistance for ß-lactams was accentuated for both bacterial groups, showing variability for macrolides and lincosamides and for the remaining antibiotics tested, low percentages of resistance were found. The results show that S. aureus is the most frequent species of the genus; followed by S. epidermidis and S. haemolyticus, among coagulase negative. Both groups of microorganism express phenotypes of resistance to penicillin and erythromycin, sensitivity to vancomycin and teicoplanin and variable susceptibility to the rest of evaluated antibiotics.

Detección de cassette cromosómico en cepas de Staphylococcus aureus resistente a meticilina aisladas en un hospital universitario de la ciudad de Maracaibo / Detection of chromosomal cassette in MRSA Staphylococcus aureus strains isolated in a University Hospital in Maracaibo City

Staphylococcus aureus resistente a meticilina, es un importante patógeno nosocomial y comunitario. El determinante genético de resistencia es el gen mecA. Se han descrito 11 tipos de SCCmec, encontrándose con frecuencia los tipos II, III en infecciones hospitalarias, y los tipos IV y V en infecciones comunitarias. La presente investigación se llevó a cabo para estudiar la distribución de los tipos de SCCmec y su relación con la Leucocidina Panton-Valentine, tipificados mediante la reacción en Cadena de la Polimerasa. Para ello se estudiaron un total de 42 cepas resistentes a meticilina portadoras del gen mecA. Veintinueve (29) cepas mostraron la presencia del cassette cromosomal tipo IV (69,05%); 30,95% presentaron el SCCmec tipo I. Un 61,95% (n=13) de las cepas fueron portadoras del SCCmec IV resultando todas positivas para el gen PVL. Cabe destacar la diseminación del cassette tipo IV en cepas intrahospitalarias portadoras de PVL, lo que es preocupante tanto para la terapéutica como para el agravamiento de las infecciones en los pacientes.

Methicillin-resistant Staphylococcus aureus is an important nosocomial and community pathogen. The genetic determinant of resistance is the mecA gene. 11 types of SCCmec have been described, with types II, III frequently found in hospital infections, and types IV and V in community infections. The present investigation was carried out to study the distribution of the SCCmec types and their relation with the Panton-Valentine Leucocidin, typified by the reaction in the Polymerase Chain. To this end, a total of 42 methicillin-resistant strains carrying the mecA gene were studied. Twenty-nine (29) strains showed the presence of type IV chromosomal cassette (69.05%); 30.95% presented SCCmec type I. A 61.95% (n= 13) of the strains were carriers of SCCmec IV, all of which were positive for the PVL gene. It is worth noting the dissemination of the type IV cassette in intrahospital strains carrying PVL, which is worrisome both for the therapeutic and for the aggravation of infections in patients.

Distribución de especies y susceptibilidad antimicrobiana en cepas de Enterococcus de origen clínico / Distribution of species and antimicrobial susceptibility in Enterococcus strains of clinical origin

A fin de establecer la frecuencia de aislamiento de las diferentes especies de enterococos, su distribución de acuerdo al tipo de muestra y servicio de atención al paciente y determinar la resistencia antimicrobiana, se analizaron 1.624 cepas provenientes de cultivos bacteriológicos de pacientes atendidos en el Centro de Referencia Bacteriológica del Servicio Autónomo Hospital Universitario de Maracaibo, durante el período Enero 2010 - Diciembre 2015. Las especies más frecuentes fueron E. faecalis (52,46%) y E. faecium (41,38%). El mayor número de cepas se obtuvo a partir de muestras de piel y tejidos blandos (54,92%), orina (23,15%) y sangre (17,27%). Los servicios con mayor frecuencia de aislamiento fueron: hospitalización de adultos (47,71%) y hospitalización pediátrica (16,38%). No se encontró asociación estadísticamente significativa entre la especie de enterococos y el tipo de muestra o el servicio de atención al paciente (p>0,05). Se detectó más resistencia en E. faecium que en E. faecalis. Los enterococos están adquiriendo cada vez mayor resistencia antimicrobiana y, por lo tanto, se hace necesario mantener una vigilancia permanente sobre ellos, realizar su adecuada identificación y detectar oportunamente la resistencia, con el fin de aplicar medidas preventivas adecuadas antes de que estos microorganismos causen un mayor impacto intrahospitalario.

In order to establish the frequency of isolation of the different species of enterococci, their distribution according to the type of sample and patient care service and determine the antimicrobial resistance, 1,624 strains obtained from bacteriological cultures of patients attended in the Bacteriological Reference Center at the Autonomous Service University Hospital of Maracaibo, during the period January 2010 - December 2015, were analyzed. The most frequent species were E. faecalis (52.46%) and E. faecium (41.38%). The greatest number of strains was obtained from skin and soft tissues samples (54.92%), urine (23.15%) and blood (17.27%). Services with increased frequency of isolation were: hospitalization of adults (47.71%) and pediatric hospitalization (16.38%). It did not find statistically significant association between the specie of enterococci and sample type, or patient care service (p > 0.05). It was detected more resistance in E. faecium than in E. faecalis. The enterococci are acquiring ever greater antimicrobial resistance, and therefore, it is necessary to maintain permanent vigilance over them, perform their proper identification and timely detect resistance, in order to apply preventive measures before these microorganisms cause a greater intrahospital impact.