Azithromycin effect on multidrug resistant Acinetobacter baumannii biofilm production and composition.

OBJECTIVES: To evaluate the effect of azithromycin (AZM) on biofilm formation and composition in multidrug resistant (MDR) Acinetobacter baumannii. MATERIAL AND METHODS: Ninety-six A. baumannii isolates were studied. Antimicrobial susceptibility and sub-minimum inhibitory concentration (sub-MIC) were determined by the broth microdilution method. Carbapenemase genes were detected by polymerase chain reaction and clonal diversity by pulsed-field gel electrophoresis (PFGE). Biofilm formation without AZM and AZM sub-MIC were determined by crystal violet staining. AZM-free biofilm composition and AZM sub-MIC were determined by detachment assays. RESULTS: The selected A. baumannii were MDR; 93.8% were carbapenem-resistant and 24 were OXA-24-positive. PFGE showed predominance of clones A (53%), B (34.7%) and C (12.5%). Biofilm production at AZM sub-MICs decreased in 53.1%, increased in 34.7% and showed no differences in 12.5% of isolates, in comparison with biofilm production without AZM. CONCLUSION: AZM sub-MIC can reduce biofilm production in A. baumannii MDR isolates with decreased protein and DNA in the biofilm. Our results may be useful in synergy studies for new therapeutic alternatives.

OBJETIVOS: Evaluar el efecto de la azitromicina (AZM) en la formación y composición de biopelículas en Acinetobacter baumannii resistente a múltiples fármacos (MDR). MATERIAL Y MÉTODOS: Se estudiaron 96 aislamientos de A. baumannii. La susceptibilidad antimicrobiana y la concentración inhibitoria submínima (sub-MIC) se determinaron por el método de microdilución del caldo. Los genes carbapenemasa fueron detectados por reacción en cadena de la polimerasa y la diversidad clonal por electroforesis en gel de campos pulsados (PFGE). La formación de biopelículas sin AZM y la sub-MIC de AZM por tinción de cristal violeta. La composición de la biopelícula sin AZM y la sub-MIC de AZM se determinaron mediante ensayos de desprendimiento. RESULTADOS: Los A. baumannii seleccionados fueron MDR; el 93.8% resistentes al carbapenem y 24 OXA-24 positivos. El PFGE demostró predominancia en los clones A (53%), B (34.7%) y C (12.5%). La producción de biopelículas en sub-MIC de AZM disminuyó en un 53.1%, aumentó en un 34.7% y no mostró diferencias en un 12.5% de los aislamientos, comparado con la producción de biopelículas sin AZM. CONCLUSIÓN: La sub-MIC de AZM puede reducir la producción de biopelículas en aislamientos de A. baumannii MDR con disminución de proteínas y el ADN en la biopelícula. Nuestros resultados pueden ser útiles en estudios de sinergia para nuevas alternativas terapéuticas.

Randomized Clinical Trial Using Sterile Single Use and Reused Polyvinylchloride Catheters for Intermittent Catheterization with a Clean Technique in Spina Bifida Cases: Short-Term Urinary Tract Infection Outcomes.

PURPOSE: Urinary tract infections are common and severe complications in patients with spina bifida. Management includes intermittent bladder catheterization with single use or reused sterile catheters. There is insufficient evidence to set a standard among the different techniques. We determined whether single use polyvinylchloride catheters would reduce urinary tract infections compared to reused polyvinylchloride catheters in patients with neurogenic bladder due to spina bifida. MATERIALS AND METHODS: We performed a 2-arm randomized parallel clinical trial from 2015 to 2016 with an 8-week followup at our center in patients with neurogenic bladder caused by spina bifida. Patients were divided into single use and reused polyvinylchloride catheter groups. Evaluations were done on days 0, 7, 14, 28, 42 and 56. Participants reported symptoms and urine cultures were obtained. The primary outcome was urinary tract infection frequency, defined as positive urine culture plus fever, flank pain, malaise, or cloudy or odorous urine. Study eligibility criteria were age 2 years or greater, spina bifida diagnosis with regular clean intermittent bladder catheterization and no urinary tract infection at initial evaluation. RESULTS: The calculated sample size was 75. Of the patients 135 were screened, 83 were randomized and 75 completed followup. Mean age was 12.7 years (range 2-56) and there were 29 males and 46 females. No statistical difference was found between the single use vs reused catheter groups in the frequency of asymptomatic bacteriuria (32.4% vs 23.7%, p = 0.398) or urinary tract infections (35.2% vs 36.8%, p = 0.877). CONCLUSIONS: Single use polyvinylchloride catheters for intermittent bladder catheterization did not decrease the incidence of urinary tract infections in our patients with neurogenic bladder compared to reused polyvinylchloride catheters. These results are consistent with the 2014 Cochrane Review.

Sexually transmitted pathogens, coinfections and risk factors in patients attending obstetrics and gynecology clinics in Jalisco, Mexico.

OBJECTIVE: To determine the frequency of nine sexually transmitted pathogens, coinfections and risk factors in patients attending obstetrics and gynecology clinics in Jalisco, Mexico. MATERIALS AND METHODS: Samples from 662 patients attending obstetrics and gynecology clinics were analyzed. Treponema pallidum, HIV, and HCV were detected by serology. HPV was detected by Polimerase Chain Reaction (PCR), and its genotype was determined by Restriction Fragment Length Polymorphism (RFLP). Trichomonas vaginalis, HSV-1, HSV-2, Mycoplasma genitalium, Neisseria gonorrhoeae and T. pallidum were detected by multiplex PCR. RESULTS: By serology, HIV frequency was 6.8%, T. pallidum was 2.26%, and HCV was 0.15%. By PCR, HPV frequency was 13.9%, (more frequent genotype was 16, 33.7%), followed by T. vaginalis (14.2%), HSV-1 (8.5%), M. genitalium (2,41%), N. gonorrhoeae (2.11%), HSV-2 (1.8%), and T. pallidum (1.05%). Patients infected with T. vaginalis were more likely to have multiple coinfections (p = 0.01). CONCLUSION: The frequency of HPV, HVS-1, HSV-2, M. genitalium and T. vaginalis was lower than that reported. However, a high frequency of HIV, T. pallidum, and N. gonorrhoeae was detected.

Characterization of phenotypic and genotypic drug resistance patterns of Mycobacterium tuberculosis isolates from a city in Mexico.

INTRODUCTION: The emergence of multidrug-resistant (MDR) Mycobacterium tuberculosis strains has become a worldwide health care problem, making treatment of tuberculosis difficult. The aim of this study was to determine phenotypic resistance and gene mutations associated with MDR of clinical isolates of Mycobacterium tuberculosis from Guadalajara, Mexico. METHODS: One hundred and five isolates were subjected to drug susceptibility testing to first line drugs using the proportion and Mycobacteria Growth Indicator Tube (MGIT) methods. Genes associated with isoniazid (inhA, katG, ahpC) and rifampicin (rpoB) resistance were analyzed by either pyrosequencing or PCR-RFLP. RESULTS: Resistance to any drug was detected in 48.6% of isolates, of which 40% were isoniazid-resistant, 20% were rifampicin-resistant and 19% were MDR. Drug-resistant isolates had the following frequency of mutations in rpoB (48%), katG (14%), inhA (26%), ahpC (26%). Susceptible isolates also had a mutation in ahpC (29%). CONCLUSIONS: This is the first analysis of mutations associated with MDR of M. tuberculosis in Guadalajara. Commonly reported mutations worldwide were found in rpoB, katG and inhA genes. Substitution C to T in position -15 of the ahpC gene may possibly be a polymorphism.

Drug resistance and molecular epidemiology of Mycobacterium tuberculosis in Mexico: a systematic review.

OBJECTIVE: To compare drug resistance (DR) rates and genetic diversity of Mycobacterium tuberculosis strains from different states of Mexico. MATERIALS AND METHODS: A systematic review of English and Spanish-language articles using MEDLINE and Google Scholar. Search terms included Mycobacterium tuberculosis, Mexico, resistance, mutation and epidemiology. RESULTS: Fifteen studies for phenotypic DR rates (n=2 694), twelve studies for genotypic DR (n=748) and eleven studies for genetic diversity (n=2 044) met our inclusion criteria. Mean DR and multidrug resistance (MDR) rates were 37.5% and 20.6%, respectively. The most frequent mutations were rpoB531 (53.1%), katG315 (50.6%), embB306 (32.1%), rpsL43 (14.6%) and pncA359 (16.7%) in DR strains. Novel mutations were found. Predominant shared types were SIT53 (T1, n=188, 3.9%), SIT119 (X1, n=125, 6.9%), SIT19 (EAI2-Manila, n=80, 6.3%) and SIT42 (LAM9, n=77, 3.0%). SIT1 Beijing genotype has been reported in six states from Mexico. CONCLUSIONS: DR and MDR rates continue to increase. Genetic diversity of M. tuberculosis strains in Mexico is high. Reports of Beijing strains are increasing.

Rapid methicillin resistance detection and subspecies discrimination in Staphylococcus hominis clinical isolates by MALDI-TOF MS.

PURPOSE: Staphylococcus hominis is a coagulase-negative opportunistic pathogen responsible for implanted medical device infections. Rapid identification and virulence factors detection are crucial for appropriate antimicrobial therapy. We aimed to search protein biomarker peaks for rapid classification of antibiotic resistance and subspecies of S. hominis using MALDI-TOF MS. METHODS: S. hominis clinical isolates (n = 148) were screened for subspecies differentiation by novobiocin resistance. Biofilm composition and formation were determined by detachment assay and crystal violet staining, respectively. Antibiotic susceptibility was performed by the broth microdilution method. The search for potential biomarkers peaks was enabled by ClinProTools 3.0, flexAnalysis 3.4, and Biotools 3.2 for statistical analysis, peak visualization, and protein/peptide alignment, respectively. RESULTS: Of 148 isolates, 12.16% were classified as S. hominis subsp. novobiosepticus, 77.77% were biofilm producers, and ˃ 50% were multidrug-resistant. Two potential biomarker peaks, 8975 m/z and 9035 m/z were detected for the discrimination of methicillin resistance with a sensitivity of 96.72%. The following peaks were detected for subspecies differentiation: 2582 m/z, 2823 m/z, and 2619 m/z with 88.89-98.28% of sensitivity. CONCLUSIONS: We found potential biomarker peaks to predict methicillin resistance and discriminate S. hominis subspecies during routine MALDI-TOF MS identification in a clinical setting to enable better antibiotic treatment.

One-year surveillance of ESKAPE pathogens in an intensive care unit of Monterrey, Mexico.

BACKGROUND: Bacterial species from the ESKAPE group (i.e. Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter species) are frequently resistant to antibiotics. The purpose of this study was to monitor the incidence of ESKAPE pathogens at the intensive care unit (ICU) of a tertiary care hospital in Monterrey, Mexico. METHODS: All clinically relevant organisms isolated from June 2011 to June 2012 were included. Identification and susceptibility testing was performed using panels from Sensititre. Resistance to oxacillin, for S. aureus, and the production of extended spectrum ß-lactamases (ESBLs), for K. pneumonia, were determined as defined by the Clinical Laboratory Standards Institute. Also, the presence of vanA and vanB genes was determined in E. faecium vancomycin (VAN)-resistant isolates. RESULTS: The majority of pathogens (64.5%) isolated in the ICU unit were from the ESKAPE group. The organisms most frequently isolated were A. baumannii (15.8%) and P. aeruginosa (14.3%). A high resistance to carbapenems was detected for A. baumannii (75.3%) while 62% of S. aureus isolates were confirmed to be methicillin resistant. Of the K. pneumoniae isolates, 36.9% were ESBL producers. We detected three E. faecium VAN-resistant isolates, all of which contained the vanA gene. CONCLUSION: The presence of the ESKAPE group of pathogens is a major problem in the ICU setting. The results of this study support the implementation of special antimicrobial strategies to specifically target these microorganisms.

[Meta-analysis of diagnostic tests for the detection of COVID-19]. / Metaanálisis de pruebas diagnósticas para la detección de COVID-19.

BACKGROUND: COVID-19 disease emerged at the end of 2019 and it started to be considered a pandemic at the beginning of 2020. The reference methodology for the COVID-19 diagnosis is the RT-qPCR. OBJECTIVE: It was assessed the sensitivity and specificity of molecular test kits found on the list of tests of the Instituto de Diagnóstico y Referencia Epidemiológicos (InDRE, Institute for Epidemiologic Diagnosis and Reference). MATERIAL AND METHODS: By using the PubMed and the Google Scholar platforms, a search was carried out for articles, out of which 14 were selected, retrieving the number of samples analyzed and their status (positive or negative), according to the molecular reference method, the name of the test kit used, as well as the characteristics and results obtained, expressed as true positives, false negatives, true negatives and false positives. Sensitivity and specificity of 8 kits were calculated, with compilations of the OpenEpi, version 3.01, statistical calculators, by using the Wilson score with a 95% confidence interval. RESULTS: The sensitivity and specificity results for the kits were greater than 90%. CONCLUSIONS: Tests evaluated allow the detection of presence or absence of virus, but they can be affected by conditions during the stages of the method.

INTRODUCCIÓN: la enfermedad COVID-19 surgió a finales de 2019 y se empezó a considerar pandemia a principios de 2020. La metodología de referencia para su diagnóstico es la prueba RT-qPCR. OBJETIVO: se evalúo la sensibilidad y la especificidad de kits de pruebas moleculares que se encuentran en la lista de pruebas del Instituto de Diagnóstico y Referencia Epidemiológicos (InDRE). MATERIAL Y MÉTODOS: a partir del uso de las plataformas PubMed y Google Scholar se realizó una búsqueda de artículos, de los cuales se seleccionaron 14 y se recuperó el número de muestras analizadas y su estado (positivo o negativo) según el método molecular de referencia, el nombre del kit de prueba utilizado, así como las características y los resultados obtenidos, expresados como verdaderos positivos, falsos negativos, verdaderos negativos y falsos positivos. Se calculó la sensibilidad y la especificidad de ocho kits con la compilación de calculadoras estadísticas OpenEpi versión 3.01, mediante el método de puntos de Wilson con un intervalo de confianza de 95%. RESULTADOS: los kits evaluados tuvieron una sensibilidad y una especificidad superior al 90%. CONCLUSIONES: las pruebas permiten detectar la presencia o ausencia del virus, pero pueden verse afectadas por condiciones durante las etapas del método.

Intestinal Microbiome Changes in Fecal Microbiota Transplant (FMT) vs. FMT Enriched with Lactobacillus in the Treatment of Recurrent Clostridioides difficile Infection.

Aim: In this study, we conducted a comparative study to explore the differences in therapeutic efficacy and intestinal microbiome of fecal microbiota transplant (FMT) vs. FMT in addition with Lactobacillus (FMT-L) for treatment of recurrent Clostridioides difficile infection (R-CDI). Methods: We designed a double-blinded randomized comparative two-arm pilot multicenter study to assess the efficacy and impact in the intestinal microbiome of standard capsules of FMT vs. FMT-L enriched with 3 species of Lactobacillus for patients with R-CDI. A 90-day follow-up of 21 patients was performed, starting at the beginning of the study. From the selected patients, fecal samples were obtained at days 0, 3, 7, and 28 after treatment. Fecal samples and FMT were analyzed by 16S rRNA sequencing. Results: We included 21 patients (13 in the FMT group and 8 in the FMT-L group). Overall, both groups had a reduction in bowel movements per day, from 8.6 to 3.2 in the first 48 h (62.7% reduction, p=0.001). No severe adverse reactions or recurrences were recorded. Firmicutes were the most abundant phylum in donors. A low relative abundance of Proteobacteria was detected and mostly found in patients even at higher proportions than the donor. The donor's pool also had relatively few Bacteroidetes, and some patients showed a higher abundance of this phylum. Based on the ANOSIM R values, there is a significant difference between the microbial communities of basal samples and samples collected on day 7 (p=0.045) and at day 28 (0.041). Conclusion: Fecal microbiota transplant by capsules was clinically and genomically similar between traditional FMT and enriched FMT with Lactobacillus spp. Restoration of bacterial diversity and resolution of dysbiosis at days 7 and 28 were observed. Patients with a first episode of recurrence treated with FMT had an excellent response without severe adverse events; FMT should be considered as an early treatment during R-CDI.

Screening of biomarkers of drug resistance or virulence in ESCAPE pathogens by MALDI-TOF mass spectrometry.

Rapid identification and characterisation of drug-resistant bacterial pathogens have an important role in diagnostic and antimicrobial stewardship. Response time in the diagnosis of not only the etiological agent but also in antimicrobial susceptibility results is of utmost importance in patient treatment. In this study, matrix-assisted laser desorption ionisation-time of flight (MALDI-TOF) mass spectrometry (MS) was used to screen for biomarkers of ESCAPE (vancomycin-resistant Enterococcus faecium, methicillin-resistant Staphylococcus aureus, hypervirulent NAP1/ribotype 027 Clostridioides [Clostridium] difficile, multidrug resistant Acinetobacter baumannii, multidrug resistant Pseudomonas aeruginosa, and carbapenem-resistant Enterobacteriaceae) pathogens to predict antimicrobial resistance or hypervirulence. Several biomarkers of drug-resistant genotypes in S. aureus, A. baumannii, P. aeruginosa, and K. pneumoniae, as well as hypervirulence in C. difficile, were detected. The fastest possible susceptibility testing with MALDI-TOF MS is simultaneous detection of a characteristic drug-resistant peak and species identification in the same spectra generated in routine processing. According to our approach, resistance or virulence biomarker peaks can be identified while performing routine microbiology analysis, and no additional assays nor prolonged incubation time is needed. Outstanding biomarker peaks detected in our study should be further analysed by additional methods to identify the specific proteins involved.

The successful containment of a hospital outbreak caused by NDM-1-producing Klebsiella pneumoniae ST307 using active surveillance.

The worldwide dissemination of high-risk carbapenemase-producing Klebsiella pneumoniae clones has become a major threat to healthcare facilities. This study describes the successful containment of a hospital outbreak caused by NDM-1-producing K. pneumoniae Sequence Type (ST) 307 using active surveillance. The outbreak began when a patient was transferred from a local hospital. After 48 hours in our hospital, a tracheal aspirate was positive for a meropenem resistant and carbapenemase-producing K. pneumoniae. All patients in the medical intensive care unit (ICU) and the neurology wards were subject to contact precautions. The hospital surfaces and devices, healthcare workers, and patients from these wards were screened by cultures. Fecal swabs were placed into broth and PCR for blaKPC, blaOXA-48, blaIMP, blaVIM, and blaNDM, which were performed directly from the broth after 12 hours. PCRs were also performed on DNA extracted from carbapenemase-producing species from subcultured broths. Five and nine days later, two more patients' rectal swabs tested positive. Molecular assays identified K. pneumoniae blaNDM-1 onto a 130-kb conjugative plasmid (IncY, IncFIIs, and IncFIIY), ST307. After the three patients were discharged, monitoring continued, and after three weeks with negative results, rectal swabbing ended. In conclusion, it was possible to contain a hospital outbreak caused by NDM-1-producing K. pneumoniae ST307 through epidemiological and microbiological surveillance. With the methodology used, the detection of NDM-type genes in fecal samples was obtained in approximately 15 hours after obtaining the fecal sample.

A snapshot of antimicrobial resistance in Mexico. Results from 47 centers from 20 states during a six-month period.

AIM: We aimed to assess the resistance rates of antimicrobial-resistant, in bacterial pathogens of epidemiological importance in 47 Mexican centers. MATERIAL AND METHODS: In this retrospective study, we included a stratified sample of 47 centers, covering 20 Mexican states. Selected isolates considered as potential causatives of disease collected over a 6-month period were included. Laboratories employed their usual methods to perform microbiological studies. The results were deposited into a database and analyzed with the WHONET 5.6 software. RESULTS: In this 6-month study, a total of 22,943 strains were included. Regarding Gram-negatives, carbapenem resistance was detected in ≤ 3% in Escherichia coli, 12.5% in Klebsiella sp. and Enterobacter sp., and up to 40% in Pseudomonas aeruginosa; in the latter, the resistance rate for piperacillin-tazobactam (TZP) was as high as 19.1%. In Acinetobacter sp., resistance rates for cefepime, ciprofloxacin, meropenem, and TZP were higher than 50%. Regarding Gram-positives, methicillin resistance in Staphylococcus aureus (MRSA) was as high as 21.4%, and vancomycin (VAN) resistance reached up to 21% in Enterococcus faecium. Acinetobacter sp. presented the highest multidrug resistance (53%) followed by Klebsiella sp. (22.6%) and E. coli (19.4%). CONCLUSION: The multidrug resistance of Acinetobacter sp., Klebsiella sp. and E. coli and the carbapenem resistance in specific groups of enterobacteria deserve special attention in Mexico. Vancomycin-resistant enterococci (VRE) and MRSA are common in our hospitals. Our results present valuable information for the implementation of measures to control drug resistance.

Helicobacter pylori drug resistance: therapy changes and challenges.

INTRODUCTION: Helicobacter pylori is a Gram-negative bacterium that causes chronic gastritis, dyspepsia, peptic ulcers, and gastric cancer. Over half the world's population is infected with H. pylori, with higher prevalence in developing countries. Areas covered: In this review, current guidelines on H. pylori therapy, such as the Toronto consensus statement, the Maastricht V/Florence consensus report, and the American College of Gastroenterology guidelines, are compared. Also, we analyzed reports of antimicrobial resistance of H. pylori published in PubMed in the last years to determine current antimicrobial resistance worldwide. Expert commentary: Although H. pylori antimicrobial resistance varies by geographic area, its prevalence has been increasing over time, causing therapy failures and low eradication rates. To best optimize the management of H. pylori infection, H. pylori therapy should be based on patterns of local and individual antimicrobial resistance, if possible.

Outcomes of Clostridium difficile-infected patients managed in a common isolation unit compared with isolation in their bed of diagnosis.

Cohorting Clostridium difficile infection (CDI) patients is a strategy which has not been thoroughly evaluated. We compared clinical characteristics and outcomes of CDI patients treated in a common isolation unit (CIU) versus those treated in their bed of diagnosis. Patients treated in the CIU showed lower mortality rates and antibiotic usage; however, a higher recurrence rate was reported.

Chlorhexidine whole-body washing of patients reduces methicillin-resistant Staphylococcus aureus and has a direct effect on the distribution of the ST5-MRSA-II (New York/Japan) clone.

PURPOSE: Methicillin-resistant Staphylococcus aureus (MRSA) colonizes the skin of hospitalized patients and is associated with high morbidity and mortality. To prevent colonization and infection by S. aureus, better disinfection practices are required. Therefore, we evaluated the effect of chlorhexidine whole-body washing on hospital-acquired S. aureus infections among intensive care unit (ICU) patients in a tertiary hospital in Mexico. METHODOLOGY: The study was conducted over 18 months to evaluate the effect of 2 % chlorhexidine gluconate (CXG) whole-body washing of ICU adult patients on chlorhexidine and antibiotic resistance, biofilm production and clonal distribution of S. aureus in a tertiary care hospital. Minimum inhibitory concentrations for CXG, antibiotic susceptibility and biofilm production by S. aureus isolates were determined. Pulsed-field gel electrophoresis, multilocus sequence typing (MLST) and PCR for Panton-Valentine leucocidin (PVL) were used for molecular typing of MRSA isolates.Results/Key findings. We included 158 isolates. A reduction in antibiotic resistance in the study period was observed for clindamycin, levofloxacin, norfloxacin, oxacillin and trimethoprim/sulfamethoxazole. None of the isolates showed reduced susceptibility to CXG. Most of the isolates were non-biofilm producers (147/158). The most commonly identified clone was a descendant of the ST5-MRSA-II (New York/Japan) clone. This clone decreased during the intervention period and reappeared markedly in the post-intervention period. During the post-intervention period, two isolates were related with the clone ST8-MRSA-IV (also known as USA300). CONCLUSION: Our findings suggest that the CXG bathing favored the reduction of healthcare-associated MRSA isolates and a temporary reduction of the predominant ST5-MRSA-II (New York/Japan) clone.

Rapid spread of an ongoing outbreak of Zika virus disease in pregnant women in a Mexican hospital.

In the first nine weeks of implementation of a Zika Virus Preparedness Plan in a Mexican Public Hospital, we cared for 221 pregnant women with any signal or symptom suggesting Zika virus infection and 99 (44.8%) patients were found to be positive for Zika virus. The median age of patients was 25.3 years (range 13-49). Symptoms in PCR-positive patients were rash (91.4%) followed by headache (53.1%), myalgia (46.9%), arthralgia (45.7%), pruritus (35.8%), retroocular pain (29.6%), conjunctivitis (21%), and fever (21%). The women's epidemiologic exposure history indicates local transmission and a community outbreak.

Draft genome sequences of two opportunistic pathogenic strains of Staphylococcus cohnii isolated from human patients.

Herein, we report the draft-genome sequences and annotation of two opportunistic pathogenic strains of Staphylococcus cohnii isolated from humans. One strain (SC-57) was isolated from blood from a male patient in May 2006 and the other (SC-532) from a catheter from a male patient in June 2006. Similar to other genomes of Staphylococcus species, most genes (42%) of both strains are involved in metabolism of amino acids and derivatives, carbohydrates and proteins. Eighty (4%) genes are involved in virulence, disease, and defense and both species show phenotypic low biofilm production and evidence of increased antibiotic resistance associated to biofilm production. From both isolates, a new Staphylococcal Cassette Chromosome mec was detected: mec class A, ccr type 1. This is the first report of whole genome sequences of opportunistic S. cohnii isolated from human patients.

The carriage of interleukin-1B-31*C allele plus Staphylococcus aureus and Haemophilus influenzae increases the risk of recurrent tonsillitis in a Mexican population.

The aim of the present study was to estimate the relative contribution of immunogenetic and microbiological factors in the development of recurrent tonsillitis in a Mexican population. Patients (n = 138) with recurrent tonsillitis and an indication of tonsillectomy (mean age: 6.05 years ± 3.00; median age: 5 years, female: 58; age range: 1-15 years) and 195 non-related controls older than 18 years and a medical history free of recurrent tonsillitis were included. To evaluate the microbial contribution, tonsil swab samples from both groups and extracted tonsil samples from cases were cultured. Biofilm production of isolated bacteria was measured. To assess the immunogenetic component, DNA from peripheral blood was genotyped for the TNFA-308G/A single-nucleotide polymorphism (SNP) and for the IL1B -31C/T SNP. Normal microbiota, but no pathogens or potential pathogens, were identified from all control sample cultures. The most frequent pathogenic species detected in tonsils from cases were Staphylococcus aureus (48.6%, 67/138) and Haemophilus influenzae (31.9%, 44/138), which were found more frequently in patient samples than in samples from healthy volunteers (P < 0.0001). Importantly, 41/54 (75.9%) S. aureus isolates were biofilm producers (18 weak and 23 strong), whereas 17/25 (68%) H. influenzae isolates were biofilm producers (10 weak, and 7 strong biofilm producers). Patients with at least one copy of the IL1B-31*C allele had a higher risk of recurrent tonsillitis (OR = 4.03; 95% CI = 1.27-14.27; P = 0.013). TNFA-308 G/A alleles were not preferentially distributed among the groups. When considering the presence of IL1B-31*C plus S. aureus, IL1B-31*C plus S. aureus biofilm producer, IL1B-31*C plus H. influenzae or IL1B-31*C plus H. influenzae biofilm producer, the OR tended to infinite. Thus, the presence of IL1B-31*C allele plus the presence of S. aureus and/or H. influenzae could be related to the development of tonsillitis in this particular Mexican population.

Randomized clinical trial to evaluate the effect of fecal microbiota transplant for initial Clostridium difficile infection in intestinal microbiome.

OBJECTIVE: The aim of this study was to evaluate the impact of fecal donor-unrelated donor mix (FMT-FURM) transplantation as first-line therapy for C. difficile infection (CDI) in intestinal microbiome. METHODS: We designed an open, two-arm pilot study with oral vancomycin (250mg every 6 h for 10-14 days) or FMT-FURM as treatments for the first CDI episode in hospitalized adult patients in Hospital Universitario "Dr. Jose Eleuterio Gonzalez". Patients were randomized by a closed envelope method in a 1: 1 ratio to either oral vancomycin or FMT-FURM. CDI resolution was considered when there was a reduction on the Bristol scale of at least 2 points, a reduction of at least 50% in the number of bowel movements, absence of fever, and resolution of abdominal pain (at least two criteria). From each patient, a fecal sample was obtained at days 0, 3, and 7 after treatment. Specimens were cultured to isolate C. difficile, and isolates were characterized by PCR. Susceptibility testing of isolates was performed using the agar dilution method. Fecal samples and FMT-FURM were analyzed by 16S rRNA sequencing. RESULTS: We included 19 patients; 10 in the vancomycin arm and 9 in the FMT-FURM arm. However, one of the patients in the vancomycin arm and two patients in the FMT-FURM arm were eliminated. Symptoms resolved in 8/9 patients (88.9%) in the vancomycin group, while symptoms resolved in 4/7 patients (57.1%) after the first FMT-FURM dose (P = 0.26) and in 5/7 patients (71.4%) after the second dose (P = 0.55). During the study, no adverse effects attributable to FMT-FURM were observed in patients. Twelve isolates were recovered, most isolates carried tcdB, tcdA, cdtA, and cdtB, with an 18-bp deletion in tcdC. All isolates were resistant to ciprofloxacin and moxifloxacin but susceptible to metronidazole, linezolid, fidaxomicin, and tetracycline. In the FMT-FURM group, the bacterial composition was dominated by Firmicutes, Bacteroidetes, and Proteobacteria at all-time points and the microbiota were remarkably stable over time. The vancomycin group showed a very different pattern of the microbial composition when comparing to the FMT-FURM group over time. CONCLUSION: The results of this preliminary study showed that FMT-FURM for initial CDI is associated with specific bacterial communities that do not resemble the donors' sample.

Correction: The carriage of interleukin-1B-31*C allele plus Staphylococcus aureus and Haemophilus influenzae increases the risk of recurrent tonsillitis in a Mexican population.

[This corrects the article DOI: 10.1371/journal.pone.0178115.].