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Concerns about the costs associated with autopsy assessment of Alzheimer disease and related dementias according to 2012 NIA-AA Guidelines have been expressed since the publication of those guidelines. For this reason, we designed and validated a Condensed Protocol for the neuropathologic diagnoses of Alzheimer disease neuropathologic change, Lewy Body disease neuropathologic change, as well as chronic microvascular lesions, hippocampal sclerosis of aging, and cerebral amyloid angiopathy. In this study, the Condensed Protocol is updated to include frontotemporal lobar degeneration [FTLD] tau (corticobasal degeneration, progressive supranuclear palsy, and Pick disease), FTLD-TDP, and limbic-predominant, age-related TDP-43 encephalopathy. The same 20 brain regions are sampled and processed in 5 tissue cassettes, which reduces reagent costs by approximately 65%. Three board-certified neuropathologists were blinded to the original Northwestern University Alzheimer's Disease Research Center Original Protocol neuropathological diagnoses and all clinical history information. The results yielded near uniform agreement with the original comprehensive Alzheimer's Disease Research Center neuropathologic assessments. Diagnostic sensitivity was not impacted. In summary, our recent results show that our updated Condensed Protocol is also an accurate and less expensive alternative to the comprehensive protocols for the additional neuropathologic diagnoses of FTLD Tau and TDP43 proteinopathies.

In this work, an exploratory study was carried out to analyze, through an anti-plagiarism program, the essays prepared by a group of postgraduate students. The focus of the study is quantitative, taking as a starting point the similarity index obtained with the iThenticate application, contrasting the essays in an artisanal way for an assessment of plagiarism. In a first analysis, a similarity index of textual copying of up to 90% was detected in some works, giving feedback to each student to correct their texts. Finally, the similarity index in the final delivery of the essays was on average 20.3%. In conclusion, using iThenticate allowed a rapid analysis of the essays, and that when collating manually, the plagiarism committed was evidenced; however, providing feedback to the student about the mistakes made was conducive to improving their writing and citation.

Background Tuberculosis (TB) transmission has long been recognized as an important occupational hazard for healthcare workers (HCWs). HCWs have a 5.8% annual risk of exposure and three times greater risk of developing active TB than the general population. Methods We conducted an observational cross-sectional study between September 2014 and March 2015 among HCWs in a high-burden TB setting in Lima to estimate the prevalence of positive Tuberculin Skin Test (TST) and to investigate factors associated with a positive TST. Results Two hundred forty participants were included in the analysis; TST was administered to 190 (79.2%) while the rest were exempt due to a previous positive TST result, history of TB, or test refusal. A positive TST result was found among 56.2% of participants to whom the TST was applied (95% CI: 49.22–63.55%). When considering those who had a previous positive TST result and those with a history of TB, the prevalence of a positive TST result was 64.3% (95% CI: 57.8–70.3%). No significant differences were observed between clinical/paramedical and administrative staff in the health center. The use of N95 masks during work hours was reported by 142 (69.9%) participants. Prevalence ratios (PR) show that workers with more than 120 months as a HCW were 1.44 times more likely to be TST positive. The multivariate analysis found that HCWs with over 10 years of service were 1.52 times more likely to be TST positive. Conclusion This study supports previous reports that TB infection is an occupational hazard for HCWs. Prevention of TB transmission through control measures, as well as timely diagnosis of LTBI in this particular high-risk group, is critical for individual and public health.

Background: Tuberculosis (TB) transmission has long been recognized as an important occupational hazard for healthcare workers (HCWs). HCWs have a 5.8% annual risk of exposure and three times greater risk of developing active TB than the general population.Methods: We conducted an observational cross-sectional study between September 2014 and March 2015 among HCWs in a high-burden TB setting in Lima to estimate the prevalence of positive Tuberculin Skin Test (TST) and to investigate factors associated with a positive TST.Results: 240 participants were included in the analysis; TST was administered to 190 (79.2%) while the rest were exempt due to a previous positive TST result, history of TB, or test refusal. A positive TST result was found among 56.2% of participants to whom the TST was applied (95% CI: 49.22% - 63.55%). When considering those who had a previous positive TST result and those with a history of TB, the prevalence of a positive TST result was 64.3% (95% CI: 57.8% - 70.3%). No significant differences were observed between clinical/paramedical and administrative staff in the health center. The use of N95 masks during work hours was reported by 142 (69.9%) participants. Prevalence ratios (PR) show that workers with more than 120 months as a HCW were 1.44 times more likely to be TST positive. The multivariate analysis found that HCWs with over 10 years of service were 1.52 times more likely to be TST positive.Conclusion: This study supports previous reports that TB infection is an occupational hazard for HCWs. Prevention of TB transmission through control measures, as well as timely diagnosis of LTBI in this particular high-risk group, is critical for individual and public health.

Background Active case finding (ACF) in household contacts of tuberculosis (TB) patients is now recommended for National TB Programs (NTP) in low- and middle-income countries. However, evidence supporting these recommendations remains limited. This study evaluates the effectiveness and cost-effectiveness of ACF for household contacts of TB cases in a large TB endemic district of Lima, Peru. Methods A pragmatic stepped-wedge cluster randomized controlled trial was conducted in 34 health centers of San Juan de Lurigancho district. Centers were stratified by TB rate and randomly allocated to initiate ACF in groups of eight or nine centers at four-month intervals. In the intervention arm, NTP providers visited households of index patients to screen contacts for active TB. The control arm was routine passive case finding (PCF) of symptomatic TB cases. The primary outcomes were the crude and adjusted active TB case rates among household contacts. Program costs were directly measured, and the cost-effectiveness of the ACF intervention was determined. Findings 3222 index TB cases and 12,566 household contacts were included in the study. ACF identified more household contact TB cases than PCF, 199.29/10,000 contacts/year vs. 132.13 (incidence rate ratio of 1.51 (95% CI 1.21–1.88)). ACF was associated with an incremental cost-effectiveness ratio of US $16,400 per disability-adjusted life year averted and not cost-effective assuming a willingness-to-pay threshold for Peru of US $6360. Conclusion ACF of TB case household contacts detected significantly more secondary TB cases than PCF alone, but was not cost-effective in this setting. In threshold analyses, ACF becomes cost-effective if associated with case detection rates 2.5 times higher than existing PCF programs.

En los ultimos anos, la demanda de personal especializado en los servicios de asistencia en salud se ha incrementado; esto ha propiciado que los profesionales en esta area busquen alternativas de actualizacion que se adapten a los ritmos y las jornadas laborales de acuerdo con su contratacion. El Instituto Universitario Veracruzano ha iniciado la maestria en Administracion de los Servicios de Salud en la modalidad en linea en cuyo modelo educativo se encuentran las didacticas de tipo colaborativo. El objetivo de este articulo es analizar las valoraciones acerca de la colaboracion en linea en un grupo de 26 estudiantes del primer cuatrimestre de la asignatura en Sistemas y tecnologias de la informacion. El estudio fue de corte mixto: en lo cuantitativo se aplico un instrumento denominado Colab, con un indice de confiabilidad de alfa de Cronbach de 0,87, y en lo cualitativo se analizaron las consignas colaborativas realizadas en los foros de discusion. Los resultados senalan una aceptacion favorable para este tipo de actividades, por lo que se concluye que los ambientes virtuales de aprendizaje resultan favorables para quienes tienen un horario laboral que les impide estudiar en la modalidad presencial. Asimismo, las didacticas aplicadas en el aprendizaje en linea resultan favorables para el desarrollo de habilidades de colaboracion.

En los últimos años, la demanda de personal especializado en los servicios de asistencia en salud se ha incrementado; esto ha propiciado que los profesionales en esta área busquen alternativas de actualización que se adapten a los ritmos y las jornadas laborales de acuerdo con su contratación. El Instituto Universitario Veracruzano ha iniciado la maestría en Administración de los Servicios de Salud en la modalidad en línea en cuyo modelo educativo se encuentran las didácticas de tipo colaborativo. El objetivo de este artículo es analizar las valoraciones acerca de la colaboración en línea en un grupo de 26 estudiantes del primer cuatrimestre de la asignatura en Sistemas y tecnologías de la información. El estudio fue de corte mixto: en lo cuantitativo se aplicó un instrumento denominado Colab, con un índice de confiabilidad de alfa de Cronbach de 0,87, y en lo cualitativo se analizaron las consignas colaborativas realizadas en los foros de discusión. Los resultados señalan una aceptación favorable para este tipo de actividades, por lo que se concluye que los ambientes virtuales de aprendizaje resultan favorables para quienes tienen un horario laboral que les impide estudiar en la modalidad presencial. Asimismo, las didácticas aplicadas en el aprendizaje en línea resultan favorables para el desarrollo de habilidades de colaboración.

Summary Background Drug resistance is a challenge for the global control of tuberculosis. We examined mortality in patients with tuberculosis from high-burden countries, according to concordance or discordance of results from drug susceptibility testing done locally and in a reference laboratory. Methods This multicentre cohort study was done in Cote d'Ivoire, Democratic Republic of the Congo, Kenya, Nigeria, South Africa, Peru, and Thailand. We collected Mycobacterium tuberculosis isolates and clinical data from adult patients aged 16 years or older. Patients were stratified by HIV status and tuberculosis drug resistance. Molecular or phenotypic drug susceptibility testing was done locally and at the Swiss National Center for Mycobacteria, Zurich, Switzerland. We examined mortality during treatment according to drug susceptibility test results and treatment adequacy in multivariable logistic regression models adjusting for sex, age, sputum microscopy, and HIV status. Findings We obtained M tuberculosis isolates from 871 patients diagnosed between 2013 and 2016. After exclusion of 237 patients, 634 patients with tuberculosis were included in this analysis; the median age was 33·2 years (IQR 26·9–42·5), 239 (38%) were women, 272 (43%) were HIV-positive, and 69 (11%) patients died. Based on the reference laboratory drug susceptibility test, 394 (62%) strains were pan-susceptible, 45 (7%) monoresistant, 163 (26%) multidrug-resistant (MDR), and 30 (5%) had pre-extensively or extensively drug resistant (pre-XDR or XDR) tuberculosis. Results of reference and local laboratories were concordant for 513 (81%) of 634 patients and discordant for 121 (19%) of 634. Overall, sensitivity to detect any resistance was 90·8% (95% CI 86·5–94·2) and specificity 84·3% (80·3–87·7). Mortality ranged from 6% (20 of 336) in patients with pan-susceptible tuberculosis treated according to WHO guidelines to 57% (eight of 14) in patients with resistant strains who were under-treated. In logistic regression models, compared with concordant drug susceptibility test results, the adjusted odds ratio of death was 7·33 (95% CI 2·70–19·95) for patients with discordant results potentially leading to under-treatment. Interpretation Inaccurate drug susceptibility testing by comparison with a reference standard leads to under-treatment of drug-resistant tuberculosis and increased mortality. Rapid molecular drug susceptibility test of first-line and second-line drugs at diagnosis is required to improve outcomes in patients with MDR tuberculosis and pre-XDR or XDR tuberculosis. Funding National Institutes of Allergy and Infectious Diseases, Swiss National Science Foundation, Swiss National Center for Mycobacteria.

Objective To evaluate the diagnostic performance of manual MGIT™ (MMGIT) compared to the gold standard, Lowenstein-Jensen (LJ), in the diagnosis of pulmonary tuberculosis (TB) in a high-burden setting. Methods Individuals with suspected TB enrolled in parallel diagnostic trials during 2007-2011 were included. Two samples were obtained from each patient and inoculated into MMGIT and LJ medium. Diagnostic tests were performed, and the incremental yield of a second test and time to detection (TTD) were calculated. Analyses were performed per patient and per sample. Gold standard was based on LJ culture. Results In the per patient and per sample analysis, we evaluated 1436 patients and 4142 samples. The sensitivity and specificity for smear and MMGIT per sample were respectively 89.9%/92.2% and 97.1%/98.9%. Contamination was observed in 1.4% of samples on MMGIT. The mean TTD (days) was 11.8 for MMGIT and 22.9 for LJ. The sensitivity and specificity for smear and MMGIT per patient were respectively 89.9% and 92.2% and 97.1% and 98.3%. A second MMGIT culture had an incremental yield of 1.6%. Conclusions MMGIT has high sensitivity and specificity, regardless of smear result, with a 50% reduction in TTD compared to LJ. These features make MMGIT an acceptable TB diagnostic method for use in resource-limited settings.

SUMMARYWe compared the cost-effectiveness (CE) of an active case-finding (ACF) programme for household contacts of tuberculosis (TB) cases enrolled in first-line treatment to routine passive case-finding (PCF) within an established national TB programme in Peru. Decision analysis was used to model detection of TB in household contacts through: (1) self-report of symptomatic cases for evaluation (PCF), (2) a provider-initiated ACF programme, (3) addition of an Xpert MTB/RIF diagnostic test for a single sputum sample from household contacts, and (4) all strategies combined. CE was calculated as the incremental cost-effectiveness ratio (ICER) in terms of US dollars per disability-adjusted life years (DALYs) averted. Compared to PCF alone, ACF for household contacts resulted in an ICER of $2155 per DALY averted. The addition of the Xpert MTB/RIF diagnostic test resulted in an ICER of $3275 per DALY averted within a PCF programme and $3399 per DALY averted when an ACF programme was included. Provider-initiated ACF of household contacts in an urban setting of Lima, Peru can be highly cost-effective, even including costs to seek out contacts and perform an Xpert/MTB RIF test. ACF including Xpert MTB/RIF was not cost-effective if TB cases detected had high rates of default from treatment or poor outcomes.

Urine samples are increasingly used for diagnosing infections including Escherichia coli, Ebola virus, and Zika virus. However, extraction and concentration of nucleic acid biomarkers from urine is necessary for many molecular detection strategies such as polymerase chain reaction (PCR). Since urine samples typically have large volumes with dilute biomarker concentrations making them prone to false negatives, another impediment for urine-based diagnostics is the establishment of appropriate controls particularly to rule out false negatives. In this study, a mouse glyceraldehyde 3-phosphate dehydrogenase (GAPDH) DNA target was added to retrospectively collected urine samples from tuberculosis (TB)-infected and TB-uninfected patients to indicate extraction of intact DNA and removal of PCR inhibitors from urine samples. We tested this design on surrogate urine samples, retrospective 1 milliliter (mL) urine samples from patients in Lima, Peru and retrospective 5 mL urine samples from patients in Cape Town, South Africa. Extraction/PCR control DNA was detectable in 97% of clinical samples with no statistically significant differences among groups. Despite the inclusion of this control, there was no difference in the amount of TB IS6110 Tr-DNA detected between TB-infected and TB-uninfected groups except for samples from known HIV-infected patients. We found a increase in TB IS6110 Tr-DNA between TB/HIV co-infected patients compared to TB-uninfected/HIV-infected patients (N=18, p=0.037). The inclusion of an extraction/PCR control DNA to indicate successful DNA extraction and removal of PCR inhibitors should be easily adaptable as a sample preparation control for other acellular sample types.

Currently available nucleic acid amplification platforms for tuberculosis (TB) detection are not designed to be simple or inexpensive enough to implement in decentralized settings in countries with a high burden of disease. The loop-mediated isothermal amplification platform (LAMP) may change this. We conducted a study in adults with symptoms suggestive of TB in India, Uganda, and Peru to establish the feasibility of using TB-LAMP (Eiken Chemical Co.) in microscopy laboratories compared with using smear microscopy against a reference standard of solid and liquid cultures. Operational characteristics were evaluated as well. A total of 1,777 participants met the eligibility criteria and were included for analysis. Overall, TB-LAMP sensitivities among culture-positive samples were 97.2% (243/250; 95% confidence interval [CI], 94.3% to 98.2%) and 62.0% (88/142; 95% CI, 53.5% to 70.0%) for smear-positive and smear-negative TB, respectively, but varied widely by country and operator. Specificities ranged from 94.5% (446/472; 95% CI, 92.0% to 96.4%) to 98.0% (350/357; 95% CI, 96.0% to 99.2%) by country. A root cause analysis identified high temperatures, high humidity, and/or low reaction volumes as possible causes for false-positive results, as they may result in nonspecific amplification. The study was repeated in India with training focused on vulnerable steps and an updated protocol; 580 participants were included for analysis. Specificity in the repeat trial was 96.6% (515/533; 95% CI, 94.7% to 97.9%). To achieve acceptable performance of LAMP at the microscopy center level, significant training and infrastructure requirements are necessary.

The widespread emergence of antibiotic-resistant bacteria and a lack of new pharmaceutical development have catalyzed a need for new and innovative approaches for antibiotic drug discovery. One bottleneck in antibiotic discovery is the lack of a rapid and comprehensive method to identify compound mode of action (MOA). Since a hallmark of antibiotic action is as an inhibitor of essential cellular targets and processes, we identify a set of 308 essential genes in the clinically important pathogen Staphylococcus aureus . A total of 446 strains differentially expressing these genes were constructed in a comprehensive platform of sensitized and resistant strains. A subset of strains allows either target underexpression or target overexpression by heterologous promoter replacements with a suite of tetracycline-regulatable promoters. A further subset of 236 antisense RNA-expressing clones allows knockdown expression of cognate targets. Knockdown expression confers selective antibiotic hypersensitivity, while target overexpression confers resistance. The antisense strains were configured into a TargetArray in which pools of sensitized strains were challenged in fitness tests. A rapid detection method measures strain responses toward antibiotics. The TargetArray antibiotic fitness test results show mechanistically informative biological fingerprints that allow MOA elucidation.

© 2015 Shah et al. Background: We designed a pragmatic stepped-wedge cluster randomized controlled trial in order to evaluate provider-initiated evaluation of household contacts (HCs) of smear positive tuberculosis (TB) cases within a routine TB program in Lima, Peru. Methods/Design: National TB program (NTP) officers of San Juan de Lurigancho District (Lima, Peru) and university-based researchers jointly designed a pragmatic stepped-wedge cluster randomized trial design in order to evaluate a planned active case finding (ACF) program for all HCs of smear-positive TB cases in 34 district healthcare centres. Randomization of time to intervention initiation was stratified by health centre TB case rate. The ACF intervention included provider-initiated home visits of all new sputum smear positive TB patients in order to evaluate household contacts for active TB. Active TB was diagnosed using symptom screening, sputum screening, chest x-ray and clinical evaluation. Once initiated, ACF was provided by NTP staff and integrated into the routine DOTS TB program activities. Discussion: This study protocol describes the pragmatic stepped-wedge cluster randomized trial of active household contact evaluations within an NTP. The stepped-wedge design met overlapping needs of local TB programmers and researchers to adequately evaluate the large-scale roll out of a new control program in a TB endemic setting. Multiple planning meetings were required to develop the necessary networks and in order to understand the operations, needs and goals of the NTP staff and researchers collaborating on this project. The advantages and challenges of using this study design in practice and within existing routine TB programs in a middle-income country context are discussed. Trial registration: ClinicalTrials.gov NCT02174380. Registered 24 Jun 2014

© 2015 Zamudio et al. Background: Tuberculosis (TB) transmission may occur with exposure to an infectious contact often in the setting of household environments, but extra-domiciliary transmission also may happen. We evaluated if using buses and/or minibuses as public transportation was associated with acquiring TB in a high incidence urban district in Lima, Peru. Methods: Newly diagnosed TB cases with no history of previous treatment and community controls were recruited from August to December 2008 for a case-control study. Crude and adjusted odd ratios (OR) and 95% confidence intervals (CI) were calculated using logistic regression to study the association between bus/minibus use and TB risk. Results: One hundred forty TB cases and 80 controls were included. The overall use of buses/minibuses was 44.9%; 53.3% (72/135) among cases and 30.4% (24/79) among controls [OR: 3.50, (95% CI: 1.60-7.64)]. In the TB group, 25.7% (36/140) of subjects reported having had a recent household TB contact, and 13% (18/139) reported having had a workplace TB contact; corresponding figures for controls were 3.8% (3/80) and 4.1% (3/73), respectively[OR: 8.88 (95% CI: 2.64-29.92), and OR: 3.89 (95% CI: 1.10-13.70)]. In multivariate analyses, age, household income, household contact and using buses/minibuses to commute to work were independently associated with TB [OR for bus/minibus use: 11.8 (95% CI: 1.45-96.07)]. Conclusions: Bus/minibus use to commute to work is associated with TB risk in this high-incidence, urban population in Lima, Peru. Measures should be implemented to prevent TB transmission through this exposure.

The effectiveness of the World Health Organization's (WHO) treatment category II regimen for tuberculosis in 124 patients was compared to that of 1147 patients receiving treatment category I in Lima, Peru following WHO's guidelines. Drug susceptibility test was available for 85% of patients. Prevalence of multi drug resistance and streptomycin resistance were 5.1% and 20.7%, respectively. Overall cure rate for regimen II was lower than that of regimen I: 67.8% (95% CI: 58.9-75.6.) vs 77.8% (95% CI: 75.3-80.2), p = 0.014. Multi-drug resistance exerted a profound effect on cure rates in both regimens. Our results support the phasing-out of treatment category II regimen in Peru.

Summary To address the need for new approaches to antibiotic drug development, we have identified a large number of essential genes for the bacterial pathogen, Staphylococcus aureus, using a rapid shotgun antisense RNA method. Staphylococcus aureus chromosomal DNA fragments were cloned into a xylose-inducible expression plasmid and transformed into S. aureus. Homology comparisons between 658 S. aureus genes identified in this particular antisense screen and the Mycoplasma genitalium genome, which contains 517 genes in total, yielded 168 conserved genes, many of which appear to be essential in M. genitalium and other bacteria. Examples are presented in which expression of an antisense RNA specifically reduces its cognate mRNA. A cell-based, drug-screening assay is also described, wherein expression of an antisense RNA confers specific sensitivity to compounds targeting that gene product. This approach enables facile assay development for high throughput screening for any essential gene, independent of its biochemical function, thereby greatly facilitating the search for new antibiotics.

Author(s): Shah, L; Choi, HW; Berrang-Ford, L; Henostroza, G; Krapp, F; Zamudio, C; Heymann, SJ; Kaufman, JS; Ciampi, A; Seas, C; Gotuzzo, E; Brewer, TF | Abstract: SettingPeru reports among the highest multidrug-resistant tuberculosis (MDR-TB) rates in the Americas, with a growing proportion in previously untreated tuberculosis (TB) cases. The identification of clusters of primary MDR-TB compared with drug-susceptible TB (DS-TB) could help prioritize interventions.ObjectiveTo examine the clustering of primary MDR-TB case residences and their proximity to high-risk locations in San Juan de Lurigancho District, Lima, Peru.DesignEnrolled primary MDR-TB and primary DS-TB cases were interviewed and their primary residence was recorded using handheld Global Positioning System devices. Kuldorff's spatial scan statistic was used for cluster detection (SaTScan(TM), v. 9.1.1). Identified clusters were visualized in Quantum Geographic Information Systems software (v1.8.0). The following cluster centers were tested: a health centre with the highest TB and MDR-TB rates (Clinic X), a hospital and two prisons. Using regression analyses, we examined predictors of primary MDR-TB cases.ResultsA statistically significant cluster of primary MDR-TB cases was identified within a 2.29 km radius around Clinic X. Proximity to Clinic X remained a significant predictor of primary MDR-TB in adjusted regression analyses.ConclusionWe identified a hotspot of primary MDR-TB cases around Clinic X in a TB-endemic area. Causes of this clustering require investigation; targeted interventions for this high-risk area should be considered.

Objetivos. Determinar los perfiles de resistencia de las quinolonas; ciprofloxacina (Cpx), ofloxacina (Ofx), gatifloxacina (Gfx) y moxifloxacina (Mfx), y de los inyectables; kanamicina (Km), amikacina (Am) y capreomicina (Cm) en cepas multidrogorresistente (MDR). Se busco la presencia de mutaciones en los genes rrs,tlyA y gyrA/B, y su posible asociacion con la resistencia a inyectables y quinolonas. Materiales y metodos. En este estudio piloto descriptivo se seleccionaron cepas MDR aisladas durante junio a diciembre de 2004, que fueron criopreservadas en el banco de muestras del Instituto de Medicina Tropical "Alexander von Humboldt" en Lima, Peru. Se determino la concentracion minima inhibitoria (CMI) para Cpx, Ofx, Gfx, Mfx, Km, Am y Cm. Se investigo las mutaciones presentes en los genes rrs, tlyA y gyrA/B a traves de un PCR convencional y posterior secuenciamiento de los productos obtenidos. Resultados. Cuatro de los once aislados presentaron resistencia contra los inyectables y en todas se observo una alta CMI; >120 μg/mL para Km y >160 μg/mL para Am y Cm. Solo dos aislados presentaron resistencia a Ofx con un CMI = 4 μg/mL. Los resultados de secuenciamiento sugirieron que la mutacion A1401T en rrs podria ser la causa molecular de resistencia a los inyectables; mientras que en este estudio no se hallo ninguna mutacion en tlyA ni en gyrA/B asociada a resistencia. Conclusiones. Este estudio sugiere una posible asociacion entre la mutacion en A1401G y la resistencia a los antibioticos inyectables.

Background: Patients with Tuberculosis (TB) are a vulnerable group for acquiring HIV infection. Therefore, countries with a concentrated HIV epidemic and high prevalence of TB should provide adequate information about HIV prevention to TB patients. Methods: We conducted a cross-sectional study to evaluate the level of knowledge on HIV prevention and transmission among newly diagnosed TB patients in Lima, Peru. The survey evaluated knowledge about HIV infection and prevention and was administered before HIV counseling and blood sampling for HIV testing were performed. Results: A total of 171 TB patients were enrolled; mean age was 31.1 years, 101 (59%) were male. The overall mean level of knowledge of HIV was 59%; but the specific mean level of knowledge on HIV transmission and prevention was only 33.3% and 41.5%, respectively. Age and level of education correlated with overall level of knowledge in the multivariate model (P-value: 0.02 and

Background Pulmonary tuberculosis (TB) persists an important contributor to the burden of diseases in developing countries. TB control success is based on the patient’s compliance to the treatment. Depressive disorders have been negatively associated with compliance of therapeutic schemes for chronic diseases. This study aimed to estimate the significance and magnitude of major depressive episode as a hazard factor for negative outcomes (NO), including abandon or death in patients receiving TB treatment. Methodology/Principal Findings A longitudinal study was conducted to evaluate the association of major depressive episode (MDE), as measured by a 5-item version of the Center for Epidemiological Studies Depression Scale (CES-D) with NO to TB treatment. Patients with confirmed TB were enrolled before the start of TB treatment. Baseline measurements included socio-demographic variables as well as the CES-D, which was also applied every month until the end of the treatment. Death and treatment default were assessed monthly. Survivor function (SF) for NO according to MDE status (CES-D≥6) at baseline (MDEb) was estimated. Cox’s Regression was performed for bivariate analyses as well as for the multivariate model. A total of 325 patients accepted to participate in the study, of which 34 where excluded for diagnosis of MDR-TB. NO was observed in 24 patients (8.2%); 109 (37%) presented MDEb. Statistically significant difference was found on the SF of patients with and without MDEb (0.85 vs. 0.96, p-value = 0.002). The hazard ratio for NO, controlled for age, sex, marital status and instruction level was 3.54 (95%CI 1.43–8.75; p-value = 0.006). Conclusion The presence of MDE at baseline is associated to NO of TB treatment. Targeting detection and treatment of MDE may improve TB treatment outcomes.

IntroductionIn high multidrug resistant (MDR) tuberculosis (TB) prevalence areas, drug susceptibility testing (DST) at diagnosis is recommended for patients with risk factors for MDR. However, this approach might miss a substantial proportion of MDR-TB in the general population. We studied primary MDR in patients considered to be at low risk of MDR-TB in Lima, Peru.MethodsWe enrolled new sputum smear-positive TB patients who did not report any MDR-TB risk factor: known exposure to a TB patient whose treatment failed or who died or who was known to have MDR-TB; immunosuppressive co-morbidities, ex prison inmates; prison and health care workers; and alcohol or drug abuse. A structured questionnaire was applied to all enrolled participants to confirm the absence of these factors and thus minimize underreporting. Sputum from all participants was cultured on Löwenstein-Jensen media and DST for first line drugs was performed using the 7H10 agar method.ResultsOf 875 participants with complete data, 23.2% (203) had risk factors for MDR-TB elicited after enrolment. Among the group with no reported risk factors who had a positive culture, we found a 6.3% (95%CI 4.4-8.3) (37/584) rate of MDR-TB. In this group no epidemiological characteristics were associated with MDR-TB. Thus, in this group, multidrug resistance occurred in patients with no identifiable risk factors.ConclusionsWe found a high rate of primary MDR-TB in a general population with no identifiable risk factors for MDR-TB. This suggests that in a high endemic area targeting patients for MDR-TB based on the presence of risk factors is an insufficient intervention.

Author(s): Brewer, Timothy F; Choi, Howard W; Seas, Carlos; Krapp, Fiorella; Zamudio, Carlos; Shah, Lena; Ciampi, Antonio; Heymann, S Jody; Gotuzzo, Eduardo | Abstract: BackgroundMultiple drug-resistance in new tuberculosis (TB) cases accounts for the majority of all multiple drug-resistant TB (MDR-TB) worldwide. Effective control requires determining which new TB patients should be tested for MDR disease, yet the effectiveness of global screening recommendations of high-risk groups is unknown.MethodsSixty MDR-TB cases with no history of previous TB treatment, 80 drug-sensitive TB and 80 community-based controls were recruited in Lima, Peru between August and December, 2008 to investigate whether recommended screening practices identify individuals presenting with MDR-TB. Odd ratios (OR) and 95% confidence intervals (CI) were calculated using logistic regression to study the association of potential risk factors with case/control variables.ResultsMDR-TB cases did not differ from drug-sensitive TB and community controls in rates of human immunodeficiency virus infection, reported hospital or prison visits in the 3 years prior to diagnosis. MDR-TB cases were more likely than drug-sensitive TB controls to have had a recent MDR-TB household contact (OR 4.66, (95% CI 1.56-13.87)); however, only 15 cases (28.3%) reported this exposure. In multivariate modeling, recent TB household contact, but not contact with an MDR-TB case, remained predictive of MDR-TB, OR 7.47, (95% CI 1.91-29.3). Living with a partner rather than parents was associated with a lower risk of MDR-TB, OR 0.15, (95% CI 0.04-0.51).ConclusionTargeted drug susceptibility testing (DST) linked to reported MDR-TB contact or other high-risk exposures does not identify the majority of new TB cases with MDR disease in Lima where it is endemic. All new TB cases should be screened with DST to identify MDR patients. These findings are likely applicable to other regions with endemic MDR-TB.

Rationale: The Xpert MTB/RIF is an automated molecular test for Mycobacterium tuberculosis that estimates bacterial burden by measuring the threshold-cycle (Ct) of its M. tuberculosis-specific real-time polymerase chain reaction. Bacterialburden is an important biomarker for disease severity, infection control risk, and response to therapy. Objectives: Evaluate bacterial load quantitation by Xpert MTB/RIF compared with conventional quantitative methods. Methods: Xpert MTB/RIF results we recompared with smear-microscopy, semiquantiative solid culture, and time-to-detection in liquid culture for 741 patients and 2,008 samples tested in a multisite clinical trial. An internal control real-time polymerase chain reaction was evaluated for its ability to identify inaccurate quantitative Xpert MTB/RIF results. Measurements and Main Results: Assays with an internal control Ct greater than 34 were likely to be inaccurately quantitated; this represented 15% of M. tuberculosis-positive tests. Excluding these, decreasing M. tuberculosis Ct was associated with increasing smear microscopy grade for smears of concentrated sputum pellets (r s = 20.77) and directly from sputum (r s = -0.71). A Ct cutoff of approximately 27.7 best predicted smear-positive status. The association between M. tuberculosis Ct and time-to-detection in liquid culture (r s = 0.68) andsemiquantitative colony counts (r s = -0.56)wasweaker than smear. Tests of paired same-patient sputum showed that highviscosity sputum samples contained x32 more M. tuberculosis than nonviscous samples. Comparisons between the grade of the acid-fast bacilli smear and Xpert MTB/RIF quantitative data across study sites enabled us to identify a site outlier inmicroscopy. Conclusions: Xpert MTB/RIF quantitation offers a new, standardized approach to measuring bacterial burden in the sputum of patients with tuberculosis.

Background Multidrug-resistant tuberculosis (MDR-TB), resistance to at least isoniazid and rifampin, is a worldwide problem. Objective To develop a clinical prediction rule to stratify risk for MDR-TB among patients with pulmonary tuberculosis. Methods Derivation and internal validation of the rule among adult patients prospectively recruited from 37 health centers (Perú), either a) presenting with a positive acid-fast bacillus smear, or b) had failed therapy or had a relapse within the first 12 months. Results Among 964 patients, 82 had MDR-TB (prevalence, 8.5%). Variables included were MDR-TB contact within the family, previous tuberculosis, cavitary radiologic pattern, and abnormal lung exam. The area under the receiver-operating curve (AUROC) was 0.76. Selecting a cut-off score of one or greater resulted in a sensitivity of 72.6%, specificity of 62.8%, likelihood ratio (LR) positive of 1.95, and LR negative of 0.44. Similarly, selecting a cut-off score of two or greater resulted in a sensitivity of 60.8%, specificity of 87.5%, LR positive of 4.85, and LR negative of 0.45. Finally, selecting a cut-off score of three or greater resulted in a sensitivity of 45.1%, specificity of 95.3%, LR positive of 9.56, and LR negative of 0.58. Conclusion A simple clinical prediction rule at presentation can stratify risk for MDR-TB. If further validated, the rule could be used for management decisions in resource-limited areas.

SummaryThe emergence of drug-resistant bacteria coupled with the limited discovery of novel chemical scaffolds and druggable targets inspires new approaches to antibiotic development. Here we describe a chemical genomics strategy based on 245 Staphylococcus aureus antisense RNA strains, each engineered for reduced expression of target genes essential for S. aureus growth. Attenuation of gene expression can sensitize cells to compounds that inhibit the activity of a gene product or associated process. Pools of strains grown competitively in the presence of bioactive compounds generate characteristic profiles of strain sensitivities reflecting compound mechanism of action. Here, we validate this approach with a structurally and mechanistically diverse set of reference antibiotics and, in the accompanying paper in this issue of Chemistry & Biology (Huber et al., 2009), demonstrate its use in the discovery of new cell wall inhibitors.

Objetivo: Describir la demografía, e identificar la morbilidad más frecuente y las tasas de mortalidad de la unidad de enfermedades infecciosas en un hospital de referencia, público y docente, localizado en el norte de Lima-Perú. Material y métodos: Se realizó un estudio retrospectivo donde se incluyeron todas las hospitalizaciones del Departamento de Enfermedades Infecciosas, Tropicales y Dermatológicas del Hospital Nacional Cayetano Heredia, entre enero de 1990 y diciembre del 2000. Se registraron los datos demográficos, las fechas de ingreso y de alta, todos los diagnósticos, y la condición al alta. Los diagnósticos fueron codificados según la Novena Revisión de la Clasificación Internacional de Enfermedades (CIE-9). Resultados: De 7192 hospitalizaciones registradas, 4603 (64%) fueron de pacientes varones, la edad media fue 39.2 ±19 años. Las hospitalizaciones prácticamente se duplicaron (de 440 a 817) durante el periodo en estudio. La edad media aumentó de 36.6 ±16.1 años a 41 ± 19.9 años, las hospitalizaciones de pacientes geriátricos aumentó de 11.8% a 21.3%, y la relación VIH/ no VIH aumentó de 0.07 a 0.25. El índice de rotación de cama aumentó de 12.2 a 22.7. Los diagnósticos más frecuentes fueron: VIH 1209 (10.2%), tuberculosis 1201 (10.1%), celulitis 653 (5.5%) y neumonía 651 (5.5%). La mortalidad hospitalaria durante el estudio fue de 8.1%, manteniéndose en promedio constante. Conclusiones: Se observó un aumento en el número de hospitalizaciones, especialmente debido a pacientes geriátricos, sin encontrarse cambios en las tasas de mortalidad. Tuberculosis y VIH fueron los diagnósticos más frecuentes en este estudio. (Rev Med Hered 2004; 15:181-187). Objective: To describe demographic characteristics, morbidity and in-hospital mortality at the infectious diseases unit in a public reference teaching hospital in northern Lima-Peru. Material and Methods: A retrospective study was conducted including all admissions from January 1st, 1990 to December 31, 2000, recorded in the discharge book of the Department of Infectious, Tropical and Dermatological Diseases of the Hospital Nacional Cayetano Heredia. Demographic characteristics, dates of admission and discharge, diagnoses, and discharge status were registered. Diagnoses were classified using the International Classification of Diseases, version 9 (ICD-9). Results: We recorded 7192 admissions, 4603 (64%) were male, the mean age was 39.2 ± 19.0 years. The number of admissions per year almost duplicated (from 440 to 817) during the study period. The mean age increased from 36.6± 16.1 to 41±19.9 years; admissions of elderly patients increased from 11.8% to 21.3%, and the HIV/non-VIH ratio increased from 0.07 to 0.25. The admission/bed ratio augmented from 12.2 to 22.7. The most frequent diagnoses were: HIV 1209 (10.2%), tuberculosis 1201 (10.1%), skin and soft tissue infections 653 (5.5%) and pneumonia 651 (5.5%). The overall in-hospital mortality was 8.1%, remaining constant throughout the study. Conclusions: There have been an increasing number of admissions in this setting, particularly of elder patients, without changes in overall mortality. Tuberculosis and HIV were the two most frequent diagnoses. (Rev Med Hered 2004;15:181-187).

In a hospital in Lima, Peru, a review of 103 Staphylococcus aureus infections was conducted during 2002. The prevalence of oxacillin-resistant S. aureus strains was 68%; 25% of strains were resistant to multiple drugs. Previous use of antibiotics and undergoing a surgical procedure during the current hospital stay were associated with the presence of an oxacillin-resistant S. aureus strain.

Identification of operon structure is critical to understanding gene regulation and function, and pathogenesis, and for identifying targets towards the development of new antibiotics in bacteria. Rec ently, the complete genome sequences of a large number of important human bacterial pathogens have become available for computational analysis, including the major human Gram-positive pathogen Staphylococcus aureus. By annotating the predicted operon structure of the S.aureus genome, we hope to facilitate the exploration of the unique biology of this organism as well as the comparative genomics across a broad range of bacteria. We have integrated several operon prediction methods and developed a consensus approach to score the likelihood of each adjacent gene pair to be co-transcribed. Gene pairs were separated into distinct operons when scores were equal to or below an empirical threshold. Using this approach, we have generated a S.aureus genome map with scores annotated at the intersections of every adjacent gene pair. This approach predicted about 864 monocistronic transcripts and 533 polycistronic operons from the protein-encoding genes in the S.aureus strain Mu50 genome. When compared with a set of experimentally determined S.aureus operons from literature sources, this method successfully predicted at least 91% of gene pairs. At the transcription unit level, this approach correctly identified at least 92% of complete operons in this dataset. This consensus approach has enabled us to predict operons with high accuracy from a genome where limited experimental evidence for operon structure is available.

Objetivo: Describir la demografía, e identificar la morbilidad más frecuente y las tasas de mortalidad de la unidad de enfermedades infecciosas en un hospital de referencia, público y docente, localizado en el norte de Lima-Perú. Material y métodos: Se realizó un estudio retrospectivo donde se incluyeron todas las hospitalizaciones del Departamento de Enfermedades Infecciosas, Tropicales y Dermatológicas del Hospital Nacional Cayetano Heredia, entre enero de 1990 y diciembre del 2000. Se registraron los datos demográficos, las fechas de ingreso y de alta, todos los diagnósticos, y la condición al alta. Los diagnósticos fueron codificados según la Novena Revisión de la Clasificación Internacional de Enfermedades (CIE-9). Resultados: De 7192 hospitalizaciones registradas, 4603 (64%) fueron de pacientes varones, la edad media fue 39.2 ±19 años. Las hospitalizaciones prácticamente se duplicaron (de 440 a 817) durante el periodo en estudio. La edad media aumentó de 36.6 ±16.1 años a 41 ± 19.9 años, las hospitalizaciones de pacientes geriátricos aumentó de 11.8% a 21.3%, y la relación VIH/ no VIH aumentó de 0.07 a 0.25. El índice de rotación de cama aumentó de 12.2 a 22.7. Los diagnósticos más frecuentes fueron: VIH 1209 (10.2%), tuberculosis 1201 (10.1%), celulitis 653 (5.5%) y neumonía 651 (5.5%). La mortalidad hospitalaria durante el estudio fue de 8.1%, manteniéndose en promedio constante. Conclusiones: Se observó un aumento en el número de hospitalizaciones, especialmente debido a pacientes geriátricos, sin encontrarse cambios en las tasas de mortalidad. Tuberculosis y VIH fueron los diagnósticos más frecuentes en este estudio.

Objetivos. Determinar los perfiles de resistencia de las quinolonas; ciprofloxacina (Cpx), ofloxacina (Ofx), gatifloxacina (Gfx) y moxifloxacina (Mfx), y de los inyectables; kanamicina (Km), amikacina (Am) y capreomicina (Cm) en cepas multidrogorresistente (MDR). Se buscó la presencia de mutaciones en los genes rrs,tlyA y gyrA/B, y su posible asociación con la resistencia a inyectables y quinolonas. Materiales y métodos. En este estudio piloto descriptivo se seleccionaron cepas MDR aisladas durante junio a diciembre de 2004, que fueron criopreservadas en el banco de muestras del Instituto de Medicina Tropical "Alexander von Humboldt" en Lima, Perú. Se determinó la concentración mínima inhibitoria (CMI) para Cpx, Ofx, Gfx, Mfx, Km, Am y Cm. Se investigó las mutaciones presentes en los genes rrs, tlyA y gyrA/B a través de un PCR convencional y posterior secuenciamiento de los productos obtenidos. Resultados. Cuatro de los once aislados presentaron resistencia contra los inyectables y en todas se observó una alta CMI; >120 μg/mL para Km y >160 μg/mL para Am y Cm. Solo dos aislados presentaron resistencia a Ofx con un CMI = 4 μg/mL. Los resultados de secuenciamiento sugirieron que la mutación A1401T en rrs podría ser la causa molecular de resistencia a los inyectables; mientras que en este estudio no se halló ninguna mutación en tlyA ni en gyrA/B asociada a resistencia. Conclusiones. Este estudio sugiere una posible asociación entre la mutación en A1401G y la resistencia a los antibióticos inyectables. Objectives. To determine the drug resistance profiles for quinolones: ciprofloxacin (CFX), ofloxacin (OFX), moxifloxacin (MFX), and gatifloxacin (GFX); and for injectables: kanamycin (KAN), amikacin (AMK), and capreomycin (CAP) in multidrug resistant (MDR) strains. We also investigated the correlation between mutations in rrs, tlyA and gyrA/B genes, and the in vitro resistance to the second-line anti-tuberculosis drugs. Materials and methods. In this pilot study we selected MDR clinical isolates collected from June-December 2004 in the Tropical Medicine Institute "Alexander von Humboldt" (Lima, Perú). The Minimum Inhibitory Concentration (MIC) of CFX, OFX, MFX, GFX, KAN, AMK and CAP for 14 clinical isolates were determined and the sequences of rrs, tlyA and gyrA/B genes were analyzed by conventional PCR followed by sequencing. Results. We obtained valid results for 11 samples. Four isolates were resistant to injectable drugs, and in all the cases the MICs were; >120 µg/mL for KAN and >160 µg/mL for AMK and CAP. Only 2 isolates were resistant to OFX with MIC = 4 µg/mL. Sequencing results suggested that the mutation A1401T in rrs gene could be the molecular cause of the resistance to injectable drugs. In this study we did not find any mutation in tlyA and gyrA/B associated to resistance. Conclusions. Our study suggests a possible association between the mutation A1401T in rrs and resistance to injectable drugs. However further studies should be done to confirm this hypothesis in Perú.