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Introduction: Tuberculosis (TB) is a re-emerging disease considered a public health concern. In the present study, we analyzed the epidemiology and drug resistance of Mycobacterium tuberculosis strains isolated from patients with pulmonary TB., Methodology: Mycobacterium tuberculosis isolates (n = 190) were obtained from patients with pulmonary TB admitted to Dr. José Eleuterio González University Hospital (UH). Each M. tuberculosis isolate was analyzed by spoligotyping (spacer oligonucleotide typing) and MIRU-VNTR (Mycobacterial Interspersed Repetitive Units-Variable Number Tandem Repeat). Drug resistance was evaluated using the Anyplex™ II MTB/MDR/XDR assay., Results: The predominant spoligotypes observed were X1 (SIT 119, n = 46), T1 (SIT 53, n = 40), H3 (SIT 50, n = 13), Beijing (SIT 1, n = 11), and EAI2-Manila (SIT 19, n = 8). MIRU-VNTR analysis showed that the locus QUB-26 had the highest allelic variability. The observed drug resistance included monoresistance to rifampicin (2.6%; n = 5), isoniazid (3.2%; n = 6), and fluoroquinolones (1.6%; n = 3) as well as multidrug resistance (5.3%; n = 10). All of the Beijing strains were susceptible. Regarding comorbidities, 13.7% (26/190) of the patients were co-infected with TB and HIV (TB+HIV+), and 31.6% (55/190) had TB along with diabetes (TB + diabetes)., Conclusions: The most prevalent lineages were X1 (SIT 119; 24.3%) and T1 (SIT 53; 21%). An alarming proportion (12.6%) of M. tuberculosis isolates presented drug resistance. To effectively manage TB, continuous surveillance of regional strain dissemination, drug resistance profiles, and TB-associated comorbidities is crucial., Competing Interests: No Conflict of Interest is declared, (Copyright (c) 2023 Amador Flores-Aréchiga, José Luis Zacarías-Hernández, Cecilia Gabriela Vázquez-Cortés, Reyes S Tamez-Guerra, Manuel de la O-Cavazos, Lydia Guadalupe Rivera-Morales, Jorge Martín Llaca-Díaz, Jorge Castro-Garza, Néstor Casillas-Vega, José Manuel Vázquez-Guillén, Cristina Rodríguez-Padilla.)

In this study, we aim to evaluate whether thoracic ultrasound (TUS) and tracheal amylase (TA) alone or in combination can predict the development of ventilator-associated pneumonia (VAP) in neurocritical patients. Consecutive adult patients with neurocritical disease with normal chest radiographs who required intensive care unit admission and mechanical ventilation between March 2015 and July 2018 were included. TUS and Amylase levels were measured during the first 24 hours and repeated 48 hours after orotracheal intubation. Forty-three patients with a median age of 34 years (17-82) were included. TUS had a sensitivity of 100% and specificity of 96.3% as a predictor of VAP within the first 48 hours when nonpattern A was observed. TA levels > 200 UI/L in the first 48 hours had a sensitivity of 87.5%, and specificity of 63% as a predictor of VAP. Moreover, no benefit of TUS plus TA compared to TUS alone as a predictor of VAP was found. The identification of abnormal TUS patterns in the first 48 hours of orotracheal intubation is a significant predictor of VAP in neurocritical patients., Competing Interests: The authors have no funding and conflicts of interest to disclose., (Copyright © 2022 the Author(s). Published by Wolters Kluwer Health, Inc.)

Background: Convalescent plasma has been widely used to treat COVID-19 and is under investigation in numerous randomized clinical trials, but results are publicly available only for a small number of trials. The objective of this study was to assess the benefits of convalescent plasma treatment compared to placebo or no treatment and all-cause mortality in patients with COVID-19, using data from all available randomized clinical trials, including unpublished and ongoing trials (Open Science Framework, https://doi.org/10.17605/OSF.IO/GEHFX )., Methods: In this collaborative systematic review and meta-analysis, clinical trial registries (ClinicalTrials.gov, WHO International Clinical Trials Registry Platform), the Cochrane COVID-19 register, the LOVE database, and PubMed were searched until April 8, 2021. Investigators of trials registered by March 1, 2021, without published results were contacted via email. Eligible were ongoing, discontinued and completed randomized clinical trials that compared convalescent plasma with placebo or no treatment in COVID-19 patients, regardless of setting or treatment schedule. Aggregated mortality data were extracted from publications or provided by investigators of unpublished trials and combined using the Hartung-Knapp-Sidik-Jonkman random effects model. We investigated the contribution of unpublished trials to the overall evidence., Results: A total of 16,477 patients were included in 33 trials (20 unpublished with 3190 patients, 13 published with 13,287 patients). 32 trials enrolled only hospitalized patients (including 3 with only intensive care unit patients). Risk of bias was low for 29/33 trials. Of 8495 patients who received convalescent plasma, 1997 died (23%), and of 7982 control patients, 1952 died (24%). The combined risk ratio for all-cause mortality was 0.97 (95% confidence interval: 0.92; 1.02) with between-study heterogeneity not beyond chance (I 2  = 0%). The RECOVERY trial had 69.8% and the unpublished evidence 25.3% of the weight in the meta-analysis., Conclusions: Convalescent plasma treatment of patients with COVID-19 did not reduce all-cause mortality. These results provide strong evidence that convalescent plasma treatment for patients with COVID-19 should not be used outside of randomized trials. Evidence synthesis from collaborations among trial investigators can inform both evidence generation and evidence application in patient care., (© 2021. The Author(s).)

A 58-year-old woman was diagnosed with severe endometriosis and had multiple gastrointestinal tract complications for many years. Candida auris and C. parapsilosis were isolated from the bloodstream. Identification of C. auris was confirmed by amplification and sequencing of the internal transcriber spacer and the D1/D2 domain of the large rRNA gene subunit. Antifungal susceptibility was tested in both isolates using the Clinical Laboratory Standards Institute protocol M27-A3/S4. The patient evolved favorably with systemic antifungal therapy consisting of caspofungin and liposomal amphotericin B.

Platelet concentrates (PCs) obtained from whole blood are produced by fractionation of the buffy coat (BC) or the platelet-rich plasma. Despite the improvements in the technologies used for the hemocomponent fractionation, the proportion of PCs that do not accomplish the quality requirements is high. This study aimed to determine whether the basal platelet and leukocyte counts are predictive factors of the quality of the PCs obtained from BC by semiautomated fractionation. Quality control registers of 196 PCs were analyzed. Gender- and age-dependence of the blood cell count and the characteristics of PCs were evaluated. Platelet yield and residual leukocytes in the PCs were correlated with the platelet and leukocyte counts and the age of the donors. Predictive efficacy was assessed, and an optimal cut-off was established. The proportions of PCs accepted and rejected by using or not the optimal cut-off were compared. 50.0% of the PCs accomplished all the quality control requirements. Female donors had a higher basal platelet count than males. A correlation was observed between basal platelets and platelet yield, but not between basal leukocytes and residual leukocytes. The basal platelet count predicted the quality of the PCs. A cut-off of 231,000 platelets/mm 3 was established, but it did not improve the proportion of accepted PCs. In conclusion, we found that the basal platelet count is correlated with the platelet yield. The basal leukocyte count is not correlated with the residual leukocytes. The established cut-off for the basal platelet count did not improve the proportion of accepted PCs., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Introduction: Algorithms have been developed to predict the platelet yield after apheresis from the donor's data, as well as the effect on the blood cell count, to extract an acceptable platelet number without affecting the donor. However, the evaluation of these algorithms has not been widely reported. This study aimed to assess the accuracy of the predictive algorithms of the Trima Accel v. 6 blood collection system., Methods: Platelet concentrates (PCs) obtained by apheresis were analyzed. Platelet count and hematocrit were compared pre- and post-apheresis. Calculated post-apheresis platelet count (CPAPC), hematocrit (CPAH), and platelet yield (CPY), and their actual values were correlated. The bias of the algorithms was assessed with Bland-Altman plots, and the prediction of the extraction of single or double platelet products was evaluated., Results: Two hundred and seventy-nine PCs were analyzed. Post-apheresis platelet count (PAPC) and hematocrit were decreased. A moderate correlation was observed between CPY and the actual yield, with a negative bias, and a trend to increase alongside the magnitude of the measurements. CPAPC and CPAH were strongly correlated with their actual values without bias. Prediction of single or double platelet product extraction showed a significant agreement with the actual outcomes., Conclusions: The predictive algorithm for the platelet yield showed bias, and a trend to underestimate the actual platelet yields when they are higher. The algorithms for the prediction of the PAPC and hematocrit did not show bias, proving their accuracy. Prediction of a single or double platelet product extraction has a strong agreement with the APY., (© 2020 Wiley Periodicals LLC.)

Osteoporosis is a chronic disease in adult women caused by menopause and some other factors, which entails deficiency of calcium in diet. Natural products are the best source of nutriments to reduce the risk of chronic diseases. Nopal ( Opuntia ficus-indica ) is a plant characterized by its nutritional components and benefits to health. Its calcium content increases with maturation process that could be beneficial for consumers. Nopal powder (NP) was elaborated from nopal harvested within 16-24 weeks of maturation, and the nutritional content was determined. An experimental clinical trial was performed to evaluate the effect of NP. A total of 69 women between 40 and 60 years old participated in the study. During 24 weeks, experimental group ( n  = 56) consumed a daily dose of 5 g of NP and control group ( n  = 13) continue with habitual diet. Changes in bone mineral density (BMD), body mass index (BMI), body fat percentage and serum calcium were assessed. Between baseline and after 24 weeks of consumption, no significant changes were found in BMD P  = .885 experimental group and P  = .970 control group, BMI P  = .865 experimental group and P  = .984 control group, body fat P  = .744 experimental group and P  = .740 control group and serum calcium P  = .282 experimental group and P  = .959 control group. These results indicate that advanced maturation NP does not have influence in bone health, BMI, and body composition in adult women.

Antimicrobial resistance is a global public health threat. Therefore, surveillance studies are important tools to help direct antimicrobial use. The aim of this study was to investigate antimicrobial resistance in Serratia marcescens isolates collected in 2016-2017 at eight medical centers from two regions of Mexico. Selected S. marcescens isolates were further tested by polymerase chain reaction to detect the presence of genes encoding the β-lactamases, SHV, TEM or CTX. Antimicrobial resistance continues to be high in Mexico, particularly to ciprofloxacin and aminoglycosides. Also, a widespread prevalence of blaTEM was detected in S. marcescens isolates.

Non-typeable Haemophilus influenzae (NTHi) is a common opportunistic bacterial pathogen that primarily infects the respiratory mucosa. This study was conducted to assess clinical and microbiological data related to disease severity in patients with lower respiratory tract infections caused by NTHi in a tertiary care hospital in Mexico. NTHi isolates were subjected to serotyping, antimicrobial susceptibility evaluationand analyses of β-lactamase production, genetic relatednessand biofilm formation. Clinical and demographic data were retrieved from patients' records. The mean age of the patients was 40.3 years; the majority (n=44, 72.1 %) were male. The main comorbidities were arterial hypertension (n=22, 36.1 %) and diabetes mellitus (n=17, 27.9 %). NTHi isolates (n=98) were recovered from tracheal aspirate (n=57, 58.2 %), sputum (n=26, 26.5 %)and bronchial aspirate (n=15, 15.3 %) specimens. Low resistance to cefotaxime (n=0, 0.0 %), rifampin (n=1, 1.1 %) and chloramphenicol (n=3, 3.2 %) and greater resistance to ampicillin (n=30, 32.3 %) and trimethoprim-sulfamethoxazole (n=49, 52.7 %) were detected. β-Lactamase production was found in 17 (17.3 %) isolates. Isolates displayed high genetic diversity, and only 10 (10.2 %) were found to be biofilm producers. The antimicrobial susceptibility patterns of biofilm-producing and non-producing isolates did not differ. Biofilm production was associated with prolonged hospital stay (P=0.05). Lower respiratory NTHi isolates from Mexico showed low antimicrobial resistance and weak biofilm production. Younger age was correlated with lower Acute Physiology and Chronic Health Evaluation II score (moderate, P=0.07; severe, P=0.03).

Background: The current gold standard method for diagnosis of central-line associated bloodstream infections (CLABSIs) requires central venous catheter removal and a positive culture of the CVC tip with a positive peripheral blood culture., Study Design: Comparative study., Methods: We compared individual blood cultures from each catheter lumen versus a pooled-blood culture bottle containing blood samples from every catheter lumen for the diagnosis of CLABSI., Results: The pooled blood culture had the same sensitivity as the individually cultured central venous catheter lumens (85%) to detect CLABSI. A high correlation was found when we compared the pooled culture with any positive lumen result (κ = 0.98) but not when compared with any single lumen., Conclusions: Sampling multiple lumens from a central line and incubating them in the same blood culture bottle is as effective as individual blood cultures for the diagnosis of colonization or CLABSI and is a better choice than sampling only 1 lumen when sending 3 different blood culture bottles is not possible., (Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.)

Background and Objective: Clostridium difficile NAP1/ribotype 027 is associated with severe disease and high mortality rates. Our aim was to determine the prevalence of NAP1/ribotype 027 among C. difficile isolates in a tertiary care hospital, and review the main clinical data., Methods: We included 106 stool samples from 106 patients. Samples were tested for A&B toxins and were cultured on CCFA agar. The genes tcdA, tcdB, tcdC, cdtA, and cdtB were amplified using PCR in clinical isolates. The tcdA 3'-end deletion analysis, PCR-ribotyping, and pulsed-field gel electrophoresis (PFGE) were also performed. Stool samples that were positive for culture were tested by the GeneXpert C. difficile assay. Clinical data were collected., Results: Thirty-six patients tested positive for A&B toxins; and 22 patients had positive culture for C. difficile, 14 of which tested positive for the A&B toxins and all 22 patients tested positive by the GeneXpert C. difficile assay. Risk factors included an average hospital stay of 16.1 days prior to toxin detection, average antibiotic use for 16.2 days, and a median of 3 antibiotics used. The 30-day crude mortality rate was 8.4%. Six of the 22 patients died, and 3 of those deaths were directly attributed to C. difficile infection. The majority of isolates, 90.9% (20/22), carried genes tcdB, tcdA, cdtA, and cdtB; and these strains carried the corresponding downregulator gene tcdC, with an 18-bp deletion. PFGE was performed on 17 isolates, and one main pattern was observed. Analysis of the ribotyping data showed similar results., Conclusion: The above findings represent the clonal spread of C. difficile in our institution, which mainly includes the NAP1/027 strain. This is the first report of C. difficile ribotype NAP1/027 in Mexico.

Stenotrophomonas maltophilia is an important multidrug-resistant nosocomial pathogen associated with high mortality. Our aim was to examine antimicrobial susceptibility, biofilm production and clonal relatedness of clinical isolates of S. maltophilia. S. maltophilia isolates were collected between 2006 and 2013 from two tertiary care hospitals in Mexico. Antimicrobial susceptibility was evaluated by the broth microdilution method. PCR was used to determine the presence of β-lactamase genes L1 and L2. Biofilm formation was assessed with crystal violet staining. Clonal relatedness was determined by PFGE. Among the 119 collected S. maltophilia isolates, 73 (61.3%) were from the respiratory tract. Resistance levels exceeded 75% for imipenem, meropenem, ampicillin, aztreonam, gentamicin and tobramycin. Resistance to trimethoprim-sulfamethoxazole was 32.8%. L1 and L2 genes were detected in 77.1% (91/118) and 66.9% (79/118) of isolates, respectively. All S. maltophilia strains were able to produce biofilms. Strains were classified as weak (47.9%, 57/119), moderate (38.7%, 46/119), or strong (13.4%, 16/119) biofilm producers. A total of 89 distinct PFGE types were identified and 21.6% (22/102) of the isolates were distributed in nine clusters. This is the first study in Mexico to reveal characteristics of clinical isolates of S. maltophilia. Clonal diversity data indicate low cross-transmission of S. maltophilia in a hospital setting. The high antibiotic resistance underscores the need for continuous surveillance of S. maltophilia in hospital settings in Mexico., (© 2014 The Authors.)

Background: Acinetobacter baumannii is 1 of the most important nosocomial pathogens and the causative agent of numerous types of infections, especially in intensive care units (ICUs). Our aim was to evaluate the effect of 2% chlorhexidine gluconate (CHG) whole-body washing of ICU patients on A baumannii in a tertiary care hospital., Methods: During the 6-month intervention period, 327 patients were subjected to whole-body bath with 2% CHG-impregnated wipes. blaIMP (active on imipenem), blaVIM (Verona integron-encoded metallo-ß-lactamase), and blaoxacillinase (OXA) of A baumannii were typed. Isolates were genotyped by pulsed-field gel electrophoresis. Minimum inhibitory concentrations (MIC) to CHG were determined by the agar dilution method and drug susceptibility determined using the broth microdilution method. Biofilm formation was determined by crystal violet staining., Results: We analyzed 80 isolates during the baseline period and 69 isolates during the intervention period. There was a decrease in the MIC₅₀ and MIC₉₀ values for CHG for isolates (8 mg/L and 16 mg/L, respectively). All isolates typed positive for OXA₅₁-like and 86% typed positive for OXA₂₄-like pulsed-field gel electrophoresis identified 2 main clone types. During the intervention period the frequency of clone A decreased and that of clone B increased. Both clones were OXA₂₄-like positive., Conclusions: The A baumannii isolates recovered from patients who received body washing with 2% CHG presented with a significant decrease in CHG MIC values associated with a change in clonality correlating with increased biofilm production., (Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.)

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 β-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., (Copyright © 2013 S. Karger AG, Basel.)

Aim: To describe the risk factors and molecular epidemiology of nosocomial bloodstream infections caused by extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae in a tertiary care hospital., Methods: Patients with enterobacteria-positive blood cultures were included. ESBL expression in the isolates was detected using the combination disk method. Antimicrobial susceptibility testing was performed using the disk diffusion method. bla(SHV), bla(TEM), and bla(CTX-M) genes were identified in the isolated strains by PCR and sequencing. Klebsiella pneumoniae isolates were genotyped by PFGE., Results: Of the 90 isolates recovered, half were found to express ESBLs. Twenty-eight (62%) of these isolates were K. pneumoniae, 8 (18%) were Escherichia coli, 6 (13%) were Enterobacter cloacae, and 3 (7%) were Serratia marcescens. Multivariate logistic regression analysis showed that the only independent risk factor associated with infection by ESBL-producing strains was use of broad-spectrum cephalosporins. None of the isolates was resistant to imipenem. The bla(SHV5) gene was detected in 84% of isolates, followed by bla(CTX-M15) (27%), bla(SHV2) (9%), and bla(SHV12) (7%). PFGE identified six clones among the 28 ESBL-producing K. pneumoniae isolates., Conclusions: ESBL-producing K. pneumoniae clones were detected throughout the hospital. Use of broad-spectrum cephalosporins is the most important risk factor associated with the proliferation of ESBL-producing strains., (Copyright © 2012 S. Karger AG, Basel.)

Objective: Compare QuickVue Influenza A+B test with real-time RT-PCR for the diagnosis of influenza AH1N1 2009., Material and Methods: Retrospective-comparative study of 135 respiratory specimens from individuals with symptoms of influenza processed from May 2009 to October 2010.The above mentioned tests were performed simultaneously. For statistic analysisthe softwareof Confidence IntervalAnalysis 2000 was used., Results: The parameters obtained were: sensitivity 62.96; specificity 94.44; negative predictive value 62.9; positive predictive value 94.44; positive likelihood ratio 11.33; negative likelihood ratio 0.39. Confidence intervals to 95,were calculated to all of the above data., Discussion: The test QuickVue InfluenzaA+B is a rapid,simple test,with lower cost than real-time RT-PCR useful for identifying the type of virus outbreaks of influenza in a given population.It correlates well with more specific test and similar reports.

Our objective was to analyse phenotypic and genetic data of extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae, Enterobacter cloacae, Escherichia coli and Serratia marcescens that cause infections in our hospital. Over a 3 year period, 342 randomly selected clinical Enterobacteriaceae isolates were tested for ESBL production and evaluated for the presence of the β-lactamase genes bla(SHV), bla(TEM,) bla(CTX-M) and bla(TLA-1). The antibiotic susceptibilities of these isolates were also determined, and the clonality of the isolates was assessed by PFGE. Based on our analyses, 33/92 (35.9 %) K. pneumoniae, 31/87 (35.6 %) Enterobacter cloacae, 24/80 (30 %) E. coli and 17/83 (20.5 %) S. marcescens were identified as ESBL producers. The presence of TEM, SHV or CTX ESBL types was detected in 99/105 (94 %) of the isolates. TLA-1 was not detected in any of the 105 isolates. The dominant ESBL types were bla(SHV-5) (n=33), bla(SHV12) (n=31) and bla(CTX-M-15) (n=30). The predominant ESBL identified in E. coli and Enterobacter cloacae isolates was CTX-M-15, whereas in K. pneumoniae and S. marcescens the predominant types were SHV-12 and SHV-5, respectively. PFGE genotyping revealed two main genetic patterns in the K. pneumoniae isolates, types SHV-12 and TEM-1+SHV-5. An outbreak caused by Enterobacter cloacae SHV-5+CTX-M-15 was detected. In contrast, most ESBL-producing isolates of E. coli and S. marcescens did not have similar PFGE banding patterns and thus were not genetically similar. Enterobacteriaceae are a concern in our hospital, especially K. pneumoniae and Enterobacter cloacae. Our results confirm that the CTX-M-15 ESBL type has spread rapidly in the hospital, and thus requires careful monitoring.

Coagulase-negative staphylococci (CNS) are increasingly recognized to cause clinically significant infections, with S. epidermidis often cited as the third most common cause of nosocomial sepsis. Among CNS, there is a high prevalence of methicillin resistance associated with staphylococcal cassette chromosome (SCCmec) elements. Although identical SCCmec types can exist in S. aureus and CNS, some novel classes of SCCmec may be unique to CNS. Differences in the accuracy of identification of CNS species and use of non-standardized methods for the detection of methicillin resistance have led to confusing data in the literature. In addition to the review of SCCmec in CNS, in this paper we report a 2-year surveillance of methicillin-resistant CNS in a tertiary-care hospital in Guadalajara, Mexico.

The objective of this study was to determine the distribution of staphylococcal cassette chromosome mec (SCCmec) elements in meticillin-resistant coagulase-negative staphylococci (MR-CoNS) isolated from a tertiary-care hospital in Mexico and to examine the relationship to drug resistance. Fifty selected MR-CoNS isolates collected from catheters (n=15), blood (n=15), bone (n=9), bronchial lavage (n=2) and urine (n=2) and one isolate each from an abscess, cerebrospinal fluid, eye, pleural effusion, synovial fluid, tracheal aspirate and wound secretion were examined. Susceptibility testing was performed by the broth microdilution method. SCCmec types were determined by multiplex PCR and PFGE was carried out as described previously for Staphylococcus aureus. Among the MR-CoNS strains studied, the most frequently isolated species were Staphylococcus epidermidis (n=26) and Staphylococcus haemolyticus (n=13). Staphylococcus cohnii (n=5), Staphylococcus hominis (n=3), Staphylococcus sciuri (n=1), Staphylococcus pasteuri (n=1) and the recently described species Staphylococcus pettenkoferi (n=1) were also identified. The most frequent MR-CoNS genotype identified was SCCmec type IVa in S. epidermidis isolates, which also showed a high diversity in their PFGE patterns. A clone was found that amplified both SCCmec III and V elements in five isolates examined. The single MR S. pettenkoferi isolate harboured SCCmec type IVd and the single MR S. pasteuri isolate harboured SCCmec type I. The carriage of SCCmec type III was associated with resistance or intermediate resistance to meropenem (P <0.05). These results confirm the high prevalence of S. epidermidis SCCmec IVa and the high genetic diversity among MR-CoNS strains. As far as is known, this is the first report describing the newly identified S. pettenkoferi possessing SCCmec IVd and S. pasteuri harbouring SCCmec type I. MR-CoNS harbouring SCCmec type III were found to be more resistant to meropenem.

Coagulase-negative staphylococcus isolates were identified using Sensititre GPID plates and API strips (n = 156). For selected isolates, partial sequencing of the 16S rRNA, sodA, and tuf genes was performed. The Sensititre plates correctly identified 68.9% of isolates, with a concordance of 86% for Staphylococcus haemolyticus and 73% for Staphylococcus epidermidis.

Our aim was to determine the prevalence of multidrug resistance of Acinetobacter baumannii and other pathogens at a tertiary-care teaching hospital in Mexico over a 3-year period. Clinical isolates of A. baumannii (n = 550), Pseudomonas aeruginosa (n = 250), some Enterobacteriaceae species (n = 500) and Staphylococcus aureus (n = 250) collected over a 3-year period were included. Susceptibility tests were performed by the broth microdilution method. 74% of A. baumannii, 40% of Escherichia coli, 34% of P. aeruginosa, 22% of Klebsiella pneumoniae, 9% of Enterobacter cloacae, and 7% of Serratia sp. were multidrug resistant. 59% of A. baumannii clinical isolates were meropenem-resistant. A. baumannii isolates from the lower respiratory tract were the most susceptible, followed by urine clinical isolates. Species from Enterobacteriaceae showed susceptibility rates higher than 90% to meropenem and tigecycline and Serratia sp. showed the highest susceptibility to the drugs evaluated. For P. aeruginosa, the most potent drug was levofloxacin, followed by meropenem and piperacillin-tazobactam. With regard to S. aureus, 96% of the isolates were susceptible to vancomycin, followed by tigecycline and minocycline (91% of strains susceptible). The high multidrug resistance observed underscores the need for surveillance of bacterial drug resistance., (Copyright © 2010 S. Karger AG, Basel.)