Gutiérrez J

Antibiotic susceptibility of bacterial strains isolated from patients with community-acquired urinary tract infections

Isolates from urine samples obtained during 1999 were identified and their susceptibility to antimicrobial agents studied along with any production of extended-spectrum beta-lactamases (ESBL) by Escherichia coli and Klebsiella pneumoniae. A total of 13774 samples were analysed using an automatic system for the detection of bacterial ATP (Coral, USA). Of these samples, 49% were reported to be positive and uncontaminated; bacteria most frequently isolated were E. coli (47%), Proteus mirabilis (7%), Enterococcus faecalis (6%) and K. pneumoniae (5%). The susceptibility studies showed 37% E. coli strains resistant to amoxycillin+clavulanate 33% to cotrimoxazole and 22% to ciprofloxacin. Seven strains of E. coli produced ESBL. Thirteen per cent of strains were resistant to cefuroxime but only (1%) to fosfomycin. Resistance to nitrofurantoin in K. pneumoniae was 38%. P. mirabilis showed 52% resistance to cotrimoxazole and 13% Staphylococcus aureus, were methicillin-resistant. E. faecalis did not show any special resistance to normal medication. Fosfomycin continued to show high activity against Gram-negative bacilli. However, enterococci, some species of staphylococci and yeasts were difficult to treat empirically. ESBL were detected in the isolates of E. coli and there were some methicillin-resistant strains of S. aureus.

Infectious agents associated with schizophrenia: A meta-analysis

Schizophrenia is a highly disabling and limiting disorder for patients and the possibility that infections by some microorganisms may be associated to its development may allow prevention and recovery. In the current study we have done a meta-analysis of studies that have assessed the possible association between detection of different infectious agents and schizophrenia. We report results that support the idea that there is a statistically significant association between schizophrenia and infection by Human Herpesvirus 2 (OR=1.34; CI 95%: 1.09-1.70; p=0.05), Borna Disease Virus (OR=2.03; CI 95%: 1.35-3.06; p<0.01), Human Endogenous Retrovirus W (OR=19.31; CI 95%: 6.74-55.29; p<0.001), Chlamydophila pneumoniae (OR=6.34; CI 95%: 2.83-14.19; p<0.001), Chlamydophila psittaci (OR=29.05; CI 95%: 8.91-94.70; p<0.001) and Toxoplasma gondii (OR=2.70; CI 95%: 1.34-4.42; p=0.005). The implications of these findings are discussed and further research options are also explicated.

Candida dubliniensis, a new fungal pathogen

There is a high interest in Candida species other than Candida albicans because of the rise and the epidemiological shifts in candidiasis. These emerging Candida species are favored by the increase of immunocompromised patients and the use of new medical practices, and m. Most oropharyngeal candidiasis can be foundare observed in those HIV‐infected patients infected with human immunodeficiency virus (HIV). Candida dubliniensis is a recently described opportunistic pathogen that is closely related to C. albicans but differs from it with respect to epidemiology, certain virulence characteristics, and the ability to develop fluconazole resistance in vitro. C. dubliniensis has been linked to oral candidiasis in AIDS patients, although it has recently been associated to invasive disease. C. dubliniensis shares diagnostic characteristics with C. albicans, as germ tube‐ and chlamydospore‐production, and it is generally misclassified as C. albicans by standard diagnostic procedures. Several recent studies have attempted to elucidate useful phenotypic and genotypic characteristics for separating both species. A large variety of methods have been developed with the aim of facilitating rapid and, accurate identification of this species. These have included differential chromogenic isolation platesculture media, direct immunological tests, and enhanced manual and automated biochemical and enzymatic panels. Chromogenic isolation media, as CHROMagar Candida, demonstrate better detection rates than traditional media, and allow the presumptive identification of C. dubliniensis by means of colony color (dark‐green colonies). API 20 C AUX system is considered a reference method, but ID 32 C strip, the VITEK Yeast Biochemical Card and the VITEK 2 ID‐YST system correctly identify most C. dubliniensis isolates, being VITEK 2 ID‐YSTthe latter the most accurate. Spectroscopic methods, such as Fourier transformed‐infrared spectroscopy, offer potential advantages. However, many authors consider that standard methods for differentiation of Candida species are time‐consuming, often insensitive and can fail to distinguish C. dubliniensis. To overcome these low sensitivity, poor specificity and intolerable delay,drawbacks, molecular tools have been developed to discriminate C. dubliniensis, and particularly those based on the polymerase chain reaction. But, molecular tools prove difficult and too complex for routine use in the clinical laboratory setting and new developments are necessary. Moreover, an increased resistance to antifungal drugs has been described. Although preliminary studies indicate that most strains of C. dubliniensis are susceptible to establishedantifungal agents, fluconazole‐resistant strains have been detected. Furthermore, fluconazole‐resistant strains are easily derived in vitro, showing an increased expression of multidrug resistance transporters, as MDR1.

Relation between Epstein-Barr virus and multiple sclerosis: analytic study of scientific production

Numerous studies have been carried out to determine whether infection by the Epstein-Barr virus (EBV) can be considered as a risk factor for multiple sclerosis (MS). This work is a meta-analysis of case–control observational studies published before January 2009 aimed at assessing the degree of association between EBV and MS infections. A Medline electronic database search was carried out using “Epstein-Barr virus” and “multiple sclerosis” as keywords, from which we selected 30 published studies that met our methodology criteria. We found an association between MS and an exposure to EBV, studied by determining the anti-VCA IgG antibodies (odds ratio [OR] = 5.5; 95% confidence interval [CI] = 3.37–8.81; p < 0.0001), anti-complex EBNA IgG (OR = 5.4; 95% CI = 2.94–9.76; p < 0.0001) and anti-EBNA-1 IgG (OR = 12.1; 95% CI = 3.13–46.89; p < 0.0001). No significant association could be found when studying anti-EA IgG (OR = 1.3; 95% CI = 0.68–2.35; p = 0.457), EBV DNA in serum (OR = 1.8; 95% CI = 0.99–3.36; p = 0.051) and DNA in brain tissues and in cerebrospinal fluid (CSF) (OR = 0.9; 95% CI = 0.38–2.01; p = 0.768). This meta-analysis detected an association between infection by EBV and MS through the investigation of antibodies, mainly anti-EBNA-1, anti-complex EBNA and anti-VCA IgG.

Contribution of a New Mutation in parE to Quinolone Resistance in Extended-Spectrum-β-Lactamase-Producing Escherichia coli Isolates

ABSTRACT Mutations in the quinolone resistance-determining regions of gyrA, gyrB, parC, and parE were studied in 30 fluoroquinolone-resistant clinical isolates of Escherichia coli producing extended-spectrum β-lactamases. Ten isolates showed a mutation in parE that was significantly associated with an increase in the MIC for fluoroquinolones.

Detection of new mutations conferring resistance to linezolid in glycopeptide-intermediate susceptibility Staphylococcus hominis subspecies hominis circulating in an intensive care unit

Glycopeptides and linezolid are the most widely used antibiotics to treat infections by methicillin-resistant Staphylococcus spp. We report the presence of various isolates of methicillin-resistant S. hominis subsp. hominis with resistance to linezolid and reduced susceptibility to glycopeptides. We studied ten blood culture isolates of S. hominis subsp. hominis from nine patients admitted to our hospital. Etest was used to study susceptibility to antibiotics commonly prescribed against staphylococci. Domain V region of the 23S rRNA gene was amplified and sequenced to detect possible mutations that confer resistance to linezolid. Pulsed-field gel electrophoresis (PFGE) was used for the clonality study of isolates. All isolates were resistant to oxacillin, gentamicin, levofloxacin, cotrimoxazole, and linezolid, and susceptible to tigecycline and daptomycin. Nine of the isolates were resistant to erythromycin and clindamycin, and showed heterogeneous resistance to glycopeptides. C2190T, G2603T, and G2474T mutations were detected in domain V of the 23S rRNA gene. PFGE showed the presence of two different clones. This report alerts to the possible appearance of clinical strains of methicillin-resistant staphylococci with intermediate resistance to glycopeptides, resistance to linezolid, and multiple resistance to other second-line antibiotics.

Epstein-Barr virus latent membrane protein-1 (LMP-1) expression in oral squamous cell carcinoma.

Objectives Epstein‐Barr virus (EBV) is frequently associated with malignant cell transformation through the action of the oncoprotein latent membrane protein‐1 (LMP‐1). The present study aimed to determine the presence of EBV in oral squamous cell carcinomas (OSCCs) and the expression of LMP‐1 in neoplastic cells of EBV‐positive OSCCs.

Serological diagnosis of Chlamydia pneumoniae infection: limitations and perspectives.

Chlamydia pneumoniae is an obligate intracellular human pathogen responsible for a wide range of acute and chronic human diseases, including pneumonia and other respiratory diseases. Serological methods for the diagnosis of C. pneumoniae infection vary widely, and several authors have reported significant inter- and intra-laboratory variability in diagnostic methods and criteria. Over the past 10 years, numerous studies have focused on the identification of specific antigens for application in serodiagnosis, including the diagnosis of persistent infections. The use of proteomics may enable the development of serological diagnosis kits that offer reliable sensitivity and specificity and might even differentiate between the various stages of infection with this pathogen.

Chlamydia pneumoniae DNA in the Arterial Wall of Patients with Peripheral Vascular Disease

AbstractBackground:Chlamydia pneumoniae is a human respiratory pathogen that has recently been related to the genesis of symptomatic atherosclerosis. C. pneumoniae has been studied more widely in relation to coronary atherosclerosis than to peripheral arterial occlusive disease (PAOD). The present study aimed to retrospectively analyze the presence of C. pneumoniae DNA in patients with PAOD. Materials and Methods: A seminested PCR method was applied on 85 samples from 71 patients with PAOD secondary to surgical treatment. The control group comprised 50 patients with chronic superficial venous insufficiency who required varicose resection surgery. Results: The number of patients, number of samples studied and percentage of patients found to be positive in the PCR study were 17, 18 and 59%, respectively, for arteries of the lower extremities: 15, 16 and 60% for aneurysm of the abdominal aorta; 22, 23 and 73% for carotid stenosis and 17, 18 and 65% for aortic stenosis. C. pneumoniae DNA was found in six external pudendal arteries (12%) of the control group, significantly lower than the incidence in the patient group (p < 0.0001). Conclusion: A causal relationship between chronic C. pneumoniae infection and PAOD cannot be ruled out. On the contrary, the high incidence of C. pneumoniae DNA detected in our patients suggest that C. pneumoniae infection may play some role in the pathogenesis of peripheral vascular disease.

Low intrathecal immune response of anti-EBNA-1 antibodies and EBV DNA from multiple sclerosis patients.

Numerous studies have been carried out to determine whether an Epstein-Barr virus (EBV) infection can be considered a risk factor for multiple sclerosis (MS), following the evidence of an increase in IgG response to nuclear antigen-1 (EBNA-1) in both serum and cerebrospinal fluid (CSF) from MS patients. However, the possible interaction between EBV and MS has still not been well characterized, and the possible pathogenic role is yet to be determined. A case-control study (76 cases and 75 controls) was conducted to investigate anti-EBV antibodies synthesis in serum and CSF through intrathecal specific IgG synthesis to EBNA-1, as well as the presence of EBV DNA in plasma, peripheral blood mononuclear cells, and CSF from MS patients. Intrathecal EBNA-1 specific IgG synthesis was detected in 6.6% MS patients and in 17.3% controls. No EBV DNA was found in plasma or CSF, and our findings showed no evidence of high intrathecal EBNA-1 specific IgG synthesis or of significant EBV DNA in CSF in MS patients.