Publications (34)99.59 Total impact
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Article: Hepatitis C virus transmission during colonoscopy evidenced by phylogenetic analysis.
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ABSTRACT: BACKGROUND: Nosocomial transmission events still play an important role in hepatitis C virus (HCV) spreading. Among most reported medical procedures involved in nosocomial transmission, endoscopy procedures remain controversial and might be underestimated. OBJECTIVE: The aim of the study was to investigate a case of nosocomial person-to-person transmission of HCV in an endoscopy unit. STUDY DESIGN: An acute HCV infection was detected in a person that had undergone a colonoscopy after an HCV-infected patient. Serum samples from both persons were subjected to a molecular epidemiology study. The HCV NS5B genetic region was amplified and directly sequenced and the E1-E2 region was amplified, cloned and sequenced (20 clones per specimen). All sequences were subjected to phylogenetic analyses. A conventional epidemiological investigation was performed to determine the most likely cause of HCV transmission. RESULTS: NS5B sequence analysis revealed that both persons were infected with closely related HCV-1b strains. Furthermore, phylogenetic analysis of E1-E2 sequences evidenced a direct transmission between patients. The epidemiological investigation pointed out to anesthetic procedures as the most likely source of HCV transmission. The index case, not having spontaneously cleared the infection 10 months after infection, required antiviral treatment, which resulted in a sustained virological response. CONCLUSIONS: The molecular epidemiology study performed provided evidence of a person-to-person transmission of HCV during a colonoscopy procedure, and the anesthetic procedure was the most likely source of HCV transmission. This study highlights the importance of strictly following standard precautions by healthcare workers in order to prevent nosocomial HCV transmission.Journal of clinical virology: the official publication of the Pan American Society for Clinical Virology 04/2013; · 3.12 Impact Factor -
Article: Rapid diagnosis of bloodstream infections with PCR followed by mass spectrometry.
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ABSTRACT: Achieving a rapid microbiological diagnosis is crucial for decreasing morbidity and mortality of patients with a bloodstream infection, as it leads to the administration of an appropriate empiric antimicrobial therapy. Molecular methods may offer a rapid alternative to conventional microbiological diagnosis involving blood culture. In this study, the performance of a new technology that uses broad-spectrum PCR coupled with mass spectrometry (PCR/ESI-MS) was evaluated for the detection of microorganisms directly from whole blood. A total of 247 whole blood samples and paired blood cultures were prospectively obtained from 175 patients with a suspicion of sepsis. Both sample types were analyzed using the PCR/ESI-MS technology, and the results were compared with those obtained by conventional identification methods. The overall agreement between conventional methods and PCR/ESI-MS performed in blood culture aliquots was 94.2% with 96.8% sensitivity and 98.5% specificity for the molecular method. When comparing conventional methods with PCR/ESI-MS performed in whole blood specimens, the overall agreement was 77.1% with 50% sensitivity and 93.8% specificity for the molecular method. Interestingly, the PCR/ESI-MS technology led to the additional identification of 13 pathogens that were not found by conventional methods. Using the PCR/ESI-MS technology the microbiological diagnosis of bloodstream infections could be anticipated in about half of the patients in our setting, including a small but significant proportion of patients newly diagnosed. Thus, this promising technology could be very useful for the rapid diagnosis of sepsis in combination with traditional methods.PLoS ONE 01/2013; 8(4):e62108. · 4.09 Impact Factor -
Article: Evolutionary dynamics of the E1-E2 viral populations during combination therapy in non-responder patients chronically infected with hepatitis C virus subtype 1b.
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ABSTRACT: Half of the patients chronically infected with hepatitis C virus (HCV) genotype 1 fail to respond to pegylated interferon alpha (PEG-IFN) and ribavirin (RBV) therapy. This study assesses the effects of treatment on the evolution of the E1-E2 viral region in non-responder patients infected with HCV-1b. Twenty-three HCV-1b chronically infected patients were studied retrospectively, including 19 non-responders to PEG-IFN/RBV therapy (11 null-responders and 8 relapsers) in the study group, and 4 untreated patients in the control group. Genetic and phylogenetic analyses of the E1-E2 viral populations were performed at baseline and at the time of treatment failure to assess changes in genetic variability and evolutionary dynamics during treatment. Baseline virological characteristics were similar in null-responders, relapsers and controls. E1-E2 genetic variability decreased during treatment in non-responders, with a more pronounced decline in relapsers than in null-responders. A specific evolutionary pattern was not observed in null-responders, while a complete substitution of viral variants found at baseline characterised relapser patients. No specific E1-E2 amino acid substitution involved in treatment failure could be identified. In conclusion, although diverse evolutionary patterns with no apparent common adaptive changes were observed during therapy, treatment failure was characterised by a decline in genetic diversity.Infection, genetics and evolution: journal of molecular epidemiology and evolutionary genetics in infectious diseases 09/2012; · 3.22 Impact Factor -
Article: Validation of a polymerase chain reaction-oligochromatography test for detection of influenza A (H1N1) 2009 virus.
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ABSTRACT: The outbreak of pandemic influenza A (H1N1) 2009 virus caused the first influenza pandemic disease of the 21st century. In August 2010, the pandemic moved into the post-pandemic period. However, localized outbreaks of various magnitudes continued with a higher rate of disease severity. The aim of this study was to assess a new polymerase chain reaction (PCR)-oligochromatographic assay (Speed-Oligo) in the diagnosis of novel influenza A (H1N1) 2009. A total of 405 nasopharyngeal aspirate specimens from 400 pediatric and adults patients with suspected infection of pandemic influenza A (H1N1) 2009 were analyzed. The sensitivity and specificity values of the Speed-Oligo assay in comparison to reverse transcriptase-PCR assay developed by the Centers for Disease Control and Prevention were 86.5% and 92.2%, respectively. The new assay is simple, rapid, and provides a good sensitivity for detection of influenza A (H1N1) 2009. This assay might be a good alternative to real-time PCR assays for laboratories not equipped with real-time PCR instruments.Diagnostic microbiology and infectious disease 12/2011; 72(2):144-9. · 2.45 Impact Factor -
Article: Comparison of 2 molecular assays and a serologic test in diagnosing Mycoplasma pneumoniae infection in paediatrics patients.
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ABSTRACT: Two commercial polymerase chain reaction (PCR) assays (a real-time PCR [Cepheid] and an oligochromatographic test [Speed-oligo]) and 1 serology test (Serodia-Myco II) for detecting Mycoplasma pneumoniae in nasopharyngeal aspirates and serum samples were studied. Among the 145 samples, 32 serum pairs were serologically positive for M. pneumoniae. Of these, in 30 nasopharyngeal aspirates, M. pneumoniae was detected using the real-time PCR assay and 25 using Speed-oligo, corresponding to a sensitivity of 93.7% and 78.1%, respectively. Among the 94 samples with negative serology, we only obtained 1 positive result by real-time PCR assay. In the group of samples from healthy children, no positive results were obtained.Diagnostic microbiology and infectious disease 12/2011; 71(4):463-6. · 2.45 Impact Factor -
Article: Comparison between two human papillomavirus genotyping assays targeting the L1 or E6/E7 region in cervical cancer biopsies.
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ABSTRACT: Human papillomavirus (HPV) testing is increasingly used in cervical cancer prevention strategies, and a variety of HPV genotyping assays have been developed. We aimed to compare the performance of two HPV genotyping techniques in formalin-fixed paraffin-embedded (FFPE) tissue specimens from a series of invasive squamous cell carcinoma (SCC) cases. Archival FFPE tissue blocks from 78 SCC cases were initially considered. DNA was extracted from dewaxed tissue sections and tested with the INNO-LiPA HPV Genotyping Extra assay (Innogenetics), and the F-HPV typing kit (Genomed) targeting the L1 and E6/E7 regions, respectively. The INNO-LiPA assay showed a higher sensitivity (98.6%) than the F-HPV assay (78.6%). A total of 12 (17.1%) biopsies showed multiple-type infections evidenced by at least one assay. Among the SCC cases tested, HPV16 and/or 18 were detected in 70% of the cases, and 18.4% of them had multiple infections with other high-risk types. Our results suggest that the INNO-LiPA assay has a better performance than the F-HPV in FFPE specimens, probably due to its smaller amplicon size and the wider range of detectable HPV types. The prevalence of multiple infections could be higher than previously reported, as evidenced by the combination of the two assays.Enfermedades Infecciosas y Microbiología Clínica 11/2011; 30(5):225-9. · 1.49 Impact Factor -
Article: Specific Mycobacterium tuberculosis T cell responses to RD1-selected peptides for the monitoring of anti-tuberculosis therapy.
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ABSTRACT: Recently, a selection of HLA class II-restricted epitopes of ESAT-6 and CFP-10 Mycobacterium tuberculosis proteins from the region of difference (RD) 1 have been described. We have evaluated the host interferon-gamma (IFN-γ) T cell response to these RD1 selected peptides at the beginning and during anti-tuberculosis therapy. We studied 29 pulmonary TB patients enrolled at the beginning of treatment and 24 enrolled during treatment. We performed T-SPOT.TB and ELISPOT with RD1 selected peptides. Patients included at the beginning of treatment responded producing IFN-γ after antigen stimulation in 89.7% by means of T-SPOT.TB and 79.3% by means of RD1 selected ELISPOT. In contrast, for patients included during treatment the percentages were 87.5% and 25%, respectively. Differences in sensitivities between patients evaluated at the beginning and during treatment were only significant for RD1 selected ELISPOT (p < 0.0001). The host immune response to RD1 selected peptides is lower than to T-SPOT.TB during therapy. Immunological assays based on RD1 selected peptides may be useful tools for studying the immune response during anti-tuberculosis therapy.Scandinavian Journal of Infectious Diseases 09/2011; 44(3):161-7. · 1.72 Impact Factor -
Article: Hepatitis C virus sequences from different patients confirm the existence and transmissibility of subtype 2q, a rare subtype circulating in the metropolitan area of Barcelona, Spain.
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ABSTRACT: The hepatitis C virus (HCV) has been classified into six genotypes and more than 70 subtypes with distinct geographical and epidemiological distributions. While 18 genotype 2 subtypes have been proposed, only 5 have had their complete sequence determined. The aim of this study was to characterize HCV isolates from three patients from the Barcelona metropolitan area of Spain for whom commercial genotyping methods provided discordant results. Full-length genome sequencing was carried out for 2 of the 3 patients; for the third patient only partial NS5B sequences could be obtained. The generated sequences were subjected to phylogenetic, recombination, and identity analyses. Sequences covering most of the HCV genome (9398 and 9566 nt in length) were obtained and showed a 90.3% identity to each other at the nucleotide level, while both sequences differed by 17.5-22.6% from the other fully sequenced genotype 2 subtypes. No evidence of recombination was found. The NS5B phylogenetic tree showed that sequences from the three patients cluster together with the only representative sequence of the provisionally designed 2q subtype, which also corresponds to a patient from Barcelona. Phylogenetic analysis of the full coding sequence showed that subtype 2q was more closely related to subtype 2k. The results obtained in this study suggest that subtype 2q now meets the requirements for confirmed designation status according to consensus criteria for HCV classification and nomenclature, and its epidemiological value is ensured as it has spread among several patients in the Barcelona metropolitan area.Journal of Medical Virology 05/2011; 83(5):820-6. · 2.82 Impact Factor -
Article: Usefulness of mid regional pro-atrial natriuretic peptide in the exacerbations of chronic obstructive pulmonary disease.
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ABSTRACT: A recent approach for the management of chronic obstructive pulmonary disease (COPD) is the measurement of systemic biomarkers. The aim of this study was to evaluate the usefulness of mid regional pro-atrial natriuretic peptide (MR-proANP) to predict short and long term prognosis. We included 318 COPD patients: 46 in a stable phase, 217 undergoing an exacerbation and 55 with pneumonia. Serum samples were collected at admission. For 20 exacerbated patients, we also collected a second sample one month later. MR-proANP was measured by an inmunofluorescent assay. Statistically higher levels of MR-proANP were found in patients with pneumonia when comparing to patients in the stable state (p=0.031). For those patients with paired samples, MR-proANP decreased statistically one month later (p=0.027). MR-proANP showed significant lower levels in exacerbations with isolation of pathogenic bacteria (p=0.011). MR-proANP levels were higher in patients that died within one month, decreasing as long as the moment of death occurred later on (p=0.163). The identification of exacerbation etiology by means of MR-proANP is not clinically reliable. Levels of MR-proANP vary depending on the clinical status, being higher during pneumonia in comparison to the stable state. MR-proANP levels were higher in patients that died within one month after the exacerbation episode.Clinica chimica acta; international journal of clinical chemistry 02/2011; 412(5-6):470-5. · 2.54 Impact Factor -
Article: Value of procalcitonin, C-reactive protein, and neopterin in exacerbations of chronic obstructive pulmonary disease.
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ABSTRACT: The identification of biological markers in order to assess different aspects of COPD is an area of growing interest. The objective of this study was to investigate whether levels of procalcitonin (PCT), C-reactive protein (CRP), and neopterin in COPD patients could be useful in identifying the etiological origin of the exacerbation and assessing its prognosis. We included 318 consecutive COPD patients: 46 in a stable phase, 217 undergoing an exacerbation, and 55 with pneumonia. A serum sample was collected from each patient at the time of being included in the study. A second sample was also collected 1 month later from 23 patients in the exacerbation group. We compared the characteristics, biomarker levels, microbiological findings, and prognosis in each patient group. PCT and CRP were measured using an immunofluorescence assay. Neopterin levels were measured using a competitive immunoassay. PCT and CRP showed significant differences among the three patient groups, being higher in patients with pneumonia, followed by patients with exacerbation (P < 0.0001). For the 23 patients with paired samples, PCT and CRP levels decreased 1 month after the exacerbation episode, while neopterin increased. Neopterin showed significantly lower levels in exacerbations with isolation of pathogenic bacteria, but no differences were found for PCT and CRP. No significant differences were found when comparing biomarker levels according to the Gram result: PCT (P = 0.191), CRP (P = 0.080), and neopterin (P = 0.109). However, median values of PCT and CRP were high for Streptococcus pneumoniae, Staphylococcus aureus, and enterobacteria. All biomarkers were higher in patients who died within 1 month after the sample collection than in patients who died later on. According to our results, biomarker levels vary depending on the clinical status. However, the identification of the etiology of infectious exacerbation by means of circulating biomarkers is encouraging, but its main disadvantage is the absence of a microbiological gold standard, to definitively demonstrate their value. High biomarker levels during an exacerbation episode correlate with the short-term prognosis, and therefore their measurement can be useful for COPD management.International Journal of COPD 01/2011; 6:157-69. -
Article: Utility of the rapid antigen detection BinaxNOW A&B test for detection of novel influenza A (H1N1) virus
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ABSTRACT: Nasopharyngeal aspirates collected during outbreak of novel influenza A (H1N1) virus in Barcelona, were tested to compare the accuracy of a rapid antigen-based rapid test (Binax) with rRT-PCR assay developed by CDC. Sensitivity, specificity and positive predictive value (PPV) of rapid test are more elevated in patients lower than 18 years old and during the acute stage of epidemic, than adult patients.Clinical Microbiology and Infection 10/2010; · 4.54 Impact Factor -
Article: [Importance of biomarkers in diagnosis, prognosis and new therapies in infectious diseases].
Enfermedades Infecciosas y Microbiología Clínica 04/2010; 28(5):263-5. · 1.49 Impact Factor -
Article: Usefulness of two new methods for diagnosing metapneumovirus infections in children.
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ABSTRACT: Human metapneumovirus (hMPV) is associated with acute respiratory tract infections, mainly in paediatric patients. The aim of this study was to evaluate the usefulness of two new commercial techniques available for the detection of hMPV in clinical samples from children: an enzyme immunoassay, hMPV EIA (Biotrin International Ltd), and a molecular assay, real-time RT-PCR (Pro hMPV Real Time Assay Kit; Prodesse). A total of 184 nasopharyngeal aspirate specimens from 173 children aged less than 5 years who were hospitalized with acute wheezing were analysed. Respiratory syncytial virus was detected in 27% of the samples, followed by influenza A virus (6%), parainfluenza virus (PIV)3 (2.2%), adenovirus (2%), PIV1 (1.1%), PIV2 (1.1%), and influenza B virus (0.5%). The presence of hMPV was tested in all samples, using the real-time RT-PCR and EIA. Real-time RT-PCR detected 13 hMPV-positive samples (8%), and EIA detected 17 (9.3%). When the EIA results were compared with those of real-time RT-PCR for the detection of hMPV, a good correlation was found (94%). A relatively low co-infection rate (15%) was observed in our patients. RT-PCR and EIA provide robust methods for the diagnosis of hMPV infection in children.Clinical Microbiology and Infection 02/2010; 16(11):1663-8. · 4.54 Impact Factor -
Article: Baseline Prediction of Combination Therapy Outcome in Hepatitis C Virus 1b Infected Patients by Discriminant Analysis Using Viral and Host Factors
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ABSTRACT: Background: Current treatment of chronic hepatitis C virus (HCV) infection has limited efficacy 2especially amonggenotype 1 infected patients2, is costly, and involves severe side effects. Thus, predicting non-response is of major interestfor both patient wellbeing and health care expense. At present, treatment cannot be individualized on the basis of anybaseline predictor of response. We aimed to identify pre-treatment clinical and virological parameters associated withtreatment failure, as well as to assess whether therapy outcome could be predicted at baseline.Methodology: Forty-three HCV subtype 1b (HCV-1b) chronically infected patients treated with pegylated-interferon alphaplus ribavirin were retrospectively studied (21 responders and 22 non-responders). Host (gender, age, weight, transaminaselevels, fibrosis stage, and source of infection) and viral-related factors (viral load, and genetic variability in the E1-E2 andCore regions) were assessed. Logistic regression and discriminant analyses were used to develop predictive models. A''leave-one-out'' cross-validation method was used to assess the reliability of the discriminant models.Principal Findings: Lower alanine transaminase levels (ALT, p = 0.009), a higher number of quasispecies variants in the E1-E2 region (number of haplotypes, nHap_E1-E2) (p = 0.003), and the absence of both amino acid arginine at position 70 andleucine at position 91 in the Core region (p = 0.039) were significantly associated with treatment failure. Therapy outcomewas most accurately predicted by discriminant analysis (90.5% sensitivity and 95.5% specificity, 85.7% sensitivity and 81.8%specificity after cross-validation); the most significant variables included in the predictive model were the Core amino acidpattern, the nHap_E1-E2, and gamma-glutamyl transferase and ALT levels.Conclusions and Significance: Discriminant analysis has been shown as a useful tool to predict treatment outcome usingbaseline HCV genetic variability and host characteristics. The discriminant models obtained in this study led to accuratepredictions in our population of Spanish HCV-1b treatment nai¨ve patients.PLoS ONE. 01/2010; 5(11). -
Article: IFN-γ response on T-cell based assays in HIV-infected patients for detection of tuberculosis infection.
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ABSTRACT: Individuals infected with human immunodeficiency virus (HIV) have an increased risk of progression to active tuberculosis following Mycobacterium tuberculosis infection. The objective of the study was to determine IFN-γ responses for the detection of latent tuberculosis infection (LTBI) with QuantiFERON-TB GOLD In Tube (QFT-G-IT) and T-SPOT.TB in HIV patients, and evaluate the influence of CD4 cell count on tests performance. We studied 75 HIV patients enrolled for ongoing studies of LTBI with T-SPOT.TB, QFN-G-IT and TST. Mean CD4 cell counts ± standard deviation was 461.29 ± 307.49 cells/μl. Eight patients had a BCG scar. T-SPOT.TB, QFN-G-IT and TST were positive in 7 (9.3%), 5 (6.7%) and 9 (12%) cases, respectively. Global agreement between QFN-G-IT and T-SPOT.TB was 89% (κ = 0.275). The overall agreement of T-SPOT.TB and QFN-G-IT with TST was 80.8% (κ = 0.019) and 89% (κ = 0.373), respectively. We have found negative IFN-γ assays results among 2 BCG-vaccinated HIV-infected individuals with a positive TST. In non BCG-vaccinated patients, QFN-G-IT and TST were positive in 5 cases (7.5%) and T-SPOT.TB in 7 (10.4%). In contrast, in BCG-vaccinated patients, only TST was positive in 4/8 (50%) of the cases. The differences obtained in the number of positive results between TST and both IFN-γ assays in BCG vaccinated patients were significant (95% CI 3-97%, p = 0.046), however, the confidence interval is very wide given the small number of patients. In patients with CD4< 200, we obtained only one (5%) positive result with T-SPOT.TB; however, QFN-G-IT and TST were negative in all cases. On the contrary, percentages of positive results in patients with CD4> 200 were 10.9% (6/55), 9.1% (5/55) and 16.4% (9/55) with T-SPOT.TB, QFN-G-IT and TST, respectively. IFN-γ tests have the benefit over TST that are less influenced by BCG vaccination, consequently they are more specific than TST. Although our number of patients with advance immunosuppression is limited, our study suggests that IFN-γ assays are influenced with level of immunosuppression. The use of IFN-γ assays could be a helpful method for diagnosing LTBI in HIV population.BMC Infectious Diseases 01/2010; 10:348. · 3.12 Impact Factor -
Article: Baseline prediction of combination therapy outcome in hepatitis C virus 1b infected patients by discriminant analysis using viral and host factors.
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ABSTRACT: Current treatment of chronic hepatitis C virus (HCV) infection has limited efficacy -especially among genotype 1 infected patients-, is costly, and involves severe side effects. Thus, predicting non-response is of major interest for both patient wellbeing and health care expense. At present, treatment cannot be individualized on the basis of any baseline predictor of response. We aimed to identify pre-treatment clinical and virological parameters associated with treatment failure, as well as to assess whether therapy outcome could be predicted at baseline. Forty-three HCV subtype 1b (HCV-1b) chronically infected patients treated with pegylated-interferon alpha plus ribavirin were retrospectively studied (21 responders and 22 non-responders). Host (gender, age, weight, transaminase levels, fibrosis stage, and source of infection) and viral-related factors (viral load, and genetic variability in the E1-E2 and Core regions) were assessed. Logistic regression and discriminant analyses were used to develop predictive models. A "leave-one-out" cross-validation method was used to assess the reliability of the discriminant models. Lower alanine transaminase levels (ALT, p=0.009), a higher number of quasispecies variants in the E1-E2 region (number of haplotypes, nHap_E1-E2) (p=0.003), and the absence of both amino acid arginine at position 70 and leucine at position 91 in the Core region (p=0.039) were significantly associated with treatment failure. Therapy outcome was most accurately predicted by discriminant analysis (90.5% sensitivity and 95.5% specificity, 85.7% sensitivity and 81.8% specificity after cross-validation); the most significant variables included in the predictive model were the Core amino acid pattern, the nHap_E1-E2, and gamma-glutamyl transferase and ALT levels. Discriminant analysis has been shown as a useful tool to predict treatment outcome using baseline HCV genetic variability and host characteristics. The discriminant models obtained in this study led to accurate predictions in our population of Spanish HCV-1b treatment naïve patients.PLoS ONE 01/2010; 5(11):e14132. · 4.09 Impact Factor -
Article: Quantitative evaluation of T-cell response after specific antigen stimulation in active and latent tuberculosis infection in adults and children.
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ABSTRACT: We have evaluated the quantitative T-cell response after specific Mycobacterium tuberculosis antigen stimulation in active tuberculosis (TB) and latent TB infection (LTBI) patients. In adults, the median number of T cells after RD1 antigen stimulation was significantly higher in active TB patients than in LTBI patients. In children, the number of responder T cells against the specific antigens was higher in active TB than in LTBI patients, although the differences were not significant. In summary, in patients with suspected clinical TB, although there is overlapping in the number of responder T cells between both groups, a T-cell count above the described threshold could suggest active TB, especially in patients with a high probability of having active TB and low probability of having LTBI. In addition, the results are consistent with the current evidence that T-cell response may indicate mycobacterial burden and disease activity.Diagnostic microbiology and infectious disease 11/2009; 65(3):236-46. · 2.45 Impact Factor -
Article: IFN-gamma-release assays to diagnose TB infection in the immunocompromised individual.
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ABSTRACT: The tuberculin skin test (TST) is used for diagnosing latent TB infection (LTBI). The main limitation of TST is its low sensitivity in populations with the highest risk of progression to active TB: immunosuppressed patients and young children. New IFN-gamma-based tests appear as an alternative to the TST. IFN-gamma-based tests seem more specific than the TST, being closely associated with LTBI factors, and not being affected by bacillus Calmette-Guérin vaccination. Indeterminate results are mainly related to immunosuppression. Looking at the available data, it seems prudent to recommend the utilization of IFN-gamma-based tests after a negative TST result, in order to increase the sensitivity of detecting LTBI cases in severely immunosuppressed patients. In summary, IFN-gamma-based tests appear to be a valuable tool, in combination with the TST, for diagnosing TB infection in immunosuppressed patients.Expert Review of Respiratory Medicine 06/2009; 3(3):309-27. -
Article: Evaluation of an array-based method for human papillomavirus detection and genotyping in comparison with conventional methods used in cervical cancer screening.
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ABSTRACT: Cervical cancer is the second-most prevalent cancer in young women around the world. Infection with human papillomavirus (HPV), especially high-risk HPV types (HR-HPV), is necessary for the development of this cancer. HPV-DNA detection is increasingly being used in cervical cancer screening programs, together with the Papanicolau smear test. We evaluated the usefulness of introducing this new array-based HPV genotyping method (i.e., Clinical Arrays Papillomavirus Humano) in the cervical cancer screening algorithm in our center. The results obtained using this method were compared to those obtained by the hybrid capture II high-risk HPV DNA test (HC-II) and Papanicolau in a selected group of 408 women. The array-based assay was performed in women that were HC-II positive or presented cytological alterations. Among 246 array-positive patients, 123 (50%) presented infection with >or=2 types, and HR-HPV types were detected in 206 (83.7%), mainly HPV-16 (24.0%). Up to 132 (33.2%) specimens were classified as ASCUS (for atypical squamous cells of undetermined significance), and only 48 (36.4%) of them were HPV-DNA positive by either assay; however, 78.7% of these cases were caused by HR-HPV types. The agreement between both HPV-DNA detection techniques was fairly good (n = 367). Screening with Papanicolau smear and HC-II tests, followed by HPV detection and genotyping, provided an optimal identification of women at risk for the development of cervical cancer. Furthermore, with the identification of specific genotypes, either in single or multiple infections, a better prediction of disease progression was achieved. The array method also made allowed us to determine the possible contribution of the available vaccines in our setting.Journal of clinical microbiology 05/2009; 47(7):2165-9. · 4.16 Impact Factor -
Article: Evaluation of interferon-gamma release assays in the diagnosis of recent tuberculosis infection in health care workers.
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ABSTRACT: Health care workers (HCWs) are a group at risk of latent tuberculosis infection (LTBI). The aims of this study were to determine IFN-gamma response by QuantiFERON-TB GOLD In Tube (QFN-G-IT) and T-SPOT.TB in HCWs, comparing the results with tuberculin skin test (TST); and to analyze the capacity of IFN-gamma tests to detect recent versus remote LTBI with a prolonged stimulation test (PST). A total of 147 HCWs were enrolled; 23 of whom were BCG vaccinated. 95 HCWs (64.6%) had a previous positive TST and were not retested; and 52 HCWs had a previous negative TST or were tested for the first time. When we analysed individuals without previous positive TST, the number of positive results for T-SPOT.TB was 12/52 (23.1%); and for QFN-G-IT, 9/52 (17.3%). The global concordance (kappa) between T-SPOT.TB and QFN-G-IT with TST was 0.754 and 0.929 respectively. Of individuals with previous positive TST, T-SPOT.TB and QFN-G-IT were negative in 51.6% (49/95) and 62.1% (59/95) respectively, decreasing the concordance to 0.321 and 0.288, respectively. In non-BCG vaccinated HCWs with previous positive TST a positive IFN-gamma test was associated with degree of exposure and diameter of TST. PST was performed in 24 HCW with previous positive TST and negative IFN-gamma tests. PST was developed in 3 cell cultures stimulated with medium alone, ESAT-6 and CFP-10, respectively. In the third and sixth day of incubation period, part of the supernatants were replaced with complete medium supplemented with (rIL)-2. On day 9, ELISPOT assay was performed. In 14 samples PST was not valid due to not having enough cells. In 8 cases, the response was negative, and in 2 cases positive, suggesting that these patients were infected with Mycobacterium tuberculosis in some point in the past. Both IFN-gamma tests showed a similar number of positive results, and concordance between the tests was excellent. None of the tests was affected by prior BCG vaccination. IFN-gamma tests are a useful tool for detecting recent infection in HCW population.PLoS ONE 02/2009; 4(8):e6686. · 4.09 Impact Factor
Top co-authors
Top Journals
Institutions
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1997–2013
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Hospital Universitari Germans Trias i Pujol
Badalona, Catalonia, Spain
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2009–2011
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Instituto de Salud Carlos III
Madrid, Madrid, Spain
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2006–2011
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University of Barcelona
- Departament de Microbiologia
Barcelona, Catalonia, Spain
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2008–2009
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Fundació Institut Investigació Germans Trias i Pujol
Badalona, Catalonia, Spain
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2004
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Autonomous University of Barcelona
- Departamento de Genética y Microbiología
Cerdanyola del Vallès, Catalonia, Spain
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