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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Knowledge, attittudes and practices of healthcare workers about prevention and control of multidrug-resistant tuberculosis at Botsabelo Hospital Maseru, Lesotho

Adebanjo, Omotayo David January 2011 (has links)
Thesis (MPH)--University of Limpopo, 2011. / Background: Tuberculosis is one of the major public health problems in Lesotho. With the occurrence of multi-drug resistant tuberculosis, little is known about the views of health care workers on this disease. The aim of this study was to investigate the knowledge, attitudes, and practices of healthcare professionals about prevention and control of MDR-TB at Botsabelo hospital, situated in Maseru, Lesotho. Methods: This study was conducted by means of a semi-structured, anonymous, and self-administered questionnaire that was sent to health care workers. Returned questionnaires were collected through designated boxes stationed at selected places at the study site from 23rd September to 13th October 2010. The investigator and his assistants collected the returned questionnaires on the 15th October 2010. Results: The results of this study indicate that, overall, less than half (47.3%) of respondents had good level of knowledge about MDR-TB; but the overwhelming majority of them held negative attitude towards patients with MDR-TB. Further analysis showed that the level of knowledge did not affect the attitude towards patients suffering from MDR-TB but it influenced their practices. Having good level of knowledge about MDR-TB was associated with good practices such as the use of protective masks and MDR-TB guidelines and involvement in educating patients about MDR-TB. Moreover, the findings of this study showed also that the attitude of respondents towards patients suffering from MDR-TB did not influence their practices. Conclusion: In conclusion, less than half of respondents had good level of knowledge about MDR-TB, but over 85.5% of them held negative attitude towards patients suffering from MDR-TB. Although the level of knowledge about MDR-TB was found not to have influenced the attitude of respondents towards patients suffering from MDR-TB; and that xi their attitude did not influence practices, good level of knowledge was positively associated with safer practices such as using protective masks, educating patients on MDR-TB, and referring to the MDR-TB guidelines manual. An educational remedial intervention is recommended.
2

Reduction of diagnostic and treatment delays reduces rifampicin-resistant tuberculosis mortality in Rwanda

Ngabonziza, J.-C.S., Habimana, Y.M., Decroo, T., Migambi, P., Dushime, A., Mazarati, J.B., Rigouts, L., Affolabi, D., Ivan, E., Meehan, Conor J., Van Deun, A., Fissette, K., Habiyambere, I., Nyaruhirira, A.U., Turate, I., Semahore, J.M., Ndjeka, N., Muvunyi, C.M., Condo, J.U., Gasana, M., Hasker, E., Torrea, G., de Jong, B.C. 28 April 2020 (has links)
Yes / SETTING: In 2005, in response to the increasing prevalence of rifampicin-resistant tuberculosis (RR-TB) and poor treatment outcomes, Rwanda initiated the programmatic management of RR-TB, including expanded access to systematic rifampicin drug susceptibility testing (DST) and standardised treatment.OBJECTIVE: To describe trends in diagnostic and treatment delays and estimate their effect on RR-TB mortality.DESIGN: Retrospective analysis of individual-level data including 748 (85.4%) of 876 patients diagnosed with RR-TB notified to the World Health Organization between 1 July 2005 and 31 December 2016 in Rwanda. Logistic regression was used to estimate the effect of diagnostic and therapeutic delays on RR-TB mortality.RESULTS: Between 2006 and 2016, the median diagnostic delay significantly decreased from 88 days to 1 day, and the therapeutic delay from 76 days to 3 days. Simultaneously, RR-TB mortality significantly decreased from 30.8% in 2006 to 6.9% in 2016. Total delay in starting multidrug-resistant TB (MDR-TB) treatment of more than 100 days was associated with more than two-fold higher odds for dying. When delays were long, empirical RR-TB treatment initiation was associated with a lower mortality.CONCLUSION: The reduction of diagnostic and treatment delays reduced RR-TB mortality. We anticipate that universal testing for RR-TB, short diagnostic and therapeutic delays and effective standardised MDR-TB treatment will further decrease RR-TB mortality in Rwanda.
3

Epidemiological impact of HIV on second - line drug resistance in patients with multidrug resistant tuberculosis in high HIV prevalent settings in South Africa

Odendaal, Ronel January 2014 (has links)
Read abstract on the attached document. / Dissertation (MSc)--University of Pretoria, 2014. / lk2014 / School of Health Systems and Public Health (SHSPH) / MSc / Unrestricted
4

Diabetes Reduces the Rate of Sputum Culture Conversion in Patients with Newly Diagnosed Multidrug Resistant Tuberculosis

Salindri, Argita 11 August 2015 (has links)
Background: Risk factors for acquired multidrug resistant tuberculosis (MDR TB) are well described but risk factors of primary MDR TB is understudied. We aimed to 1) assess risk factors for primary MDR TB, including diabetes, and 2) determine if diabetes reduced the rate of sputum culture conversion in patients with primary MDR TB. Methods: From 2011-2014 we conducted a prospective cohort study at the National Center for TB and Lung Disease in Tbilisi, Georgia. Adult (≥35 years) patients with primary TB were eligible. MDR TB was defined as resistance to at least rifampicin and isoniazid. Patients with HbA1c ≥6.5% were defined to have diabetes. Polytomous regression was used to estimate the association of patient characteristics with drug resistance. Cox regression was used to compare the hazard rate of sputum culture conversion in patients with and without diabetes. Results: Among 318 patients, 268 had drug susceptibility test results. Among patients with DST results, 19.4% was primary MDR TB and 13.4% had diabetes. In adjusted analyses, diabetes (aOR 2.51 95%CI 1.00 – 6.31) and lower socioeconomic status (aOR 3.51 95%CI 1.56 – 8.20) were associated with primary MDR TB. Among patients with primary MDR TB, 44 (84.6%) converted sputum cultures to negative. The hazard rate of sputum culture conversion was lower among patients with diabetes (aHR 0.34 95%CI 0.13 – 0.87) and among smokers (aHR 0.16 95%CI 0.04 – 0.61). Conclusions: We found diabetes to be associated with an increased risk of primary MDR TB; both diabetes and smoking were associated with a decreased rate of sputum culture conversion.
5

Managing multidrug-resistant tuberculosis in hospitalized patients at Sizwe Tropical Diseases Hospital: A five year review of treatment outcomes

Njaramba, Peter 25 October 2006 (has links)
Student number:0312412A Faculty of Health Sciences School of Public Health / Management of multidrug-resistant tuberculosis (MDR-TB) is more expensive, lengthy and is associated with less favourable outcomes and more adverse reactions than management of susceptible tuberculosis. The aim of this study was to review the management and treatment outcomes of registered MDR-TB patients hospitalized at Sizwe hospital during a five-year period. A cross-sectional study with both descriptive and analytic features was done on 237 MDR-TB patients hospitalized from the beginning of June 1998 to the end of May 2003. Data were analysed using SPSS version 12 Software. Main outcome measures were interim treatment outcomes at the end of hospitalization period. These outcomes comprised culture conversion rates, time to culture conversion, transfer out, interruption, and death rates. Multiple logistic regression analysis was performed to determine risk factors for poor treatment outcomes. These poor outcomes were defined as treatment interruption, failure and mortality rates. The burden of institutional care for MDR-TB patients in this setting was found to involve high numbers of MDR-TB patients for whom the allocated hospital beds were insufficient. Patients with primary MDR-TB, who had no history of nonadherence to treatment, were paradoxically more likely to be hospitalized shortly after diagnosis. Acquired MDR-TB patients were mostly managed as outpatients immediately after diagnosis only to be hospitalized later due to persistent nonadherence or disease severity. Overall, acquired MDR-TB patients were hospitalized in larger numbers than those with primary disease. This reflects the higher prevalence of acquired MDR-TB compared to primary MDR-TB. Page v Abstract Culture turnaround time was on average 19 days. The overall culture conversion rate of the hospitalized patients was low at 41.9 percent. This low culture conversion rate resulted in protracted hospitalization periods and high interim mortality rates. The mean duration of hospitalization, 3.52 months, correlated favourably with the time interval to the first culture conversion of 2.96 months. Hospitalization did not guarantee the expected adherence to treatment. Surgical interventions were done belatedly with resultant high mortality outcomes. The main reasons given by patients for refusing hospital treatment were visiting traditional healers, solving socioeconomic problems and attending to family matters. A large percentage of hospitalized patients were co-infected with HIV. HIV care and support was incomplete as antiretroviral drugs were not available at the hospital. Among the main findings of the study was the powerful influence HIV status had on poor hospitalization outcomes. Recommendations arising from the study include the need to provide ARVs at the Sizwe hospital. Admission and discharge guidelines aimed at ensuring adequate beds are reserved for deserving patients should be formulated. Continuing education for service providers must be encouraged and rewarded. Infection control procedures at both community and health institution level ought to be vigorously promoted. Patients known to be hopelessly non-adherent should at least be partially hospitalized in the interest of public health.
6

Unexpected high prevalence of resistance-associated Rv0678 variants in MDR-TB patients without documented prior use of clofazimine or bedaquiline.

Villellas, C., Coeck, N., Meehan, Conor J., Lounis, N., de Jong, B., Rigouts, L., Andries, K. 24 September 2019 (has links)
Yes / Objectives: Resistance-associated variants (RAVs) in Rv0678, a regulator of the MmpS5-MmpL5 efflux pump, have been shown to lead to increased MICs of bedaquiline (2- to 8- fold) and clofazimine (2- to 4-fold). The prevalence of these Rv0678 RAVs in clinical isolates and their impact on treatment outcomes are important factors to take into account in bedaquiline treatment guidelines. Methods: Baseline isolates from two bedaquiline MDR-TB clinical trials were sequenced for Rv0678 RAVs and corresponding bedaquiline MICs were determined on 7H11 agar. Rv0678 RAVs were also investigated in non-MDRTB sequences of a population-based cohort. Results: Rv0678 RAVs were identified in 23/347 (6.3%) of MDR-TB baseline isolates. Surprisingly, bedaquiline MICs for these isolates were high (>0.24 mg/L, n¼8), normal (0.03 0.24 mg/L, n¼11) or low(<0.03 mg/L, n¼4). A variant at position 11 in the intergenic region mmpS5–Rv0678 was identified in 39 isolates (11.3%) and appeared to increase the susceptibility to bedaquiline. In non-MDR-TB isolates, the frequency of Rv0678 RAVs was lower (6/ 852 or 0.7%). Competition experiments suggested that rifampicin was not the drug selecting for Rv0678 RAVs. Conclusions: RAVs in Rv0678 occur more frequently in MDR-TB patients than previously anticipated, are not associated with prior use of bedaquiline or clofazimine, and in the majority of cases do not lead to bedaquiline MICs above the provisional breakpoint (0.24mg/L). Their origin remains unknown. Given the variety of RAVs in Rv0678 and their variable effects on the MIC, only phenotypic drug-susceptibility methods can currently be used to assess bedaquiline susceptibility. / This work was supported by Janssen Pharmaceutica. N. C. was supported by a Baekeland PhD scholarship from the Flemish Institute for Scientific Technology (IWT 130308, Belgium). C. J. M., L. R. and B. d. J. were supported by a European Research Council Starting Grant INTERRUPTB (311725).
7

Análise de resistência a antimicrobianos de cepas de Mycobacterium tuberculosis isoladas no Estado de Goiás / Analysis of antimicrobial resistance of strains Mycobacterium tuberculosis strains isolated in the State of Goiás

SANTOS, Lorena Cristina 07 December 2010 (has links)
Made available in DSpace on 2014-07-29T15:26:20Z (GMT). No. of bitstreams: 1 TeseLorenaCristina2010.pdf: 1826396 bytes, checksum: fc176dacea640559fe92237b2a050e60 (MD5) Previous issue date: 2010-12-07 / Tuberculosis (TB) is a serious global public health. In Brazil for the confirmed TB cases is recommended a multi-drug therapy regimen which combines different drugs during at least 6 month. However, because of treatment inconsistency, the emergency and spread of drug resistant M. tuberculosis become a serious threat. Actually, strains resistant to at least one drug used in the TB treatment have been one of the main factor that avoid the effective TB control. According to WHO M. tuberculosis strains that are resistant to at least INH and RMP, the key drugs used in the TB treatment, are considered multidrug resistant (MDRTB). The main mutations responsible for INH and RMP resistance occur at some specific regions in the katG, inhA and rpoB genes. We analyzed by phenotypic and genotypic methods the susceptibility profile of M. tuberculosis isolated from 132 patients treated at a reference hospital in Goiânia-Goiás, between January of 2006 and July of 2007 and then performed the resistant strains genotypic identifications by RFLP-IS6110. Additionally, clinical and epidemiological informations from the patients was collected. A high frequency of drug resistance was observed in previously untreated patients (13.6% to at least one antibiotic and 6.1% MDR-TB), and a high DNA polymorphism was observed among these strains. Our results suggest that the prevalence of resistant TB in Goiás is underestimated and that resistance in new TB cases was not associated with an outbreak in this region. / A tuberculose (TB) é um problema de saúde pública em todo o mundo. Nos casos confirmados de tuberculose (TB) no Brasil, preconiza-se o esquema multidroga terapêutico que combina diferentes drogas por um período mínimo de 6 meses de tratamento. Devido, principalmente, ao tratamento inadequado, a emergência e disseminação de linhagens de M. tuberculosis multi resistentes a drogas se tornou uma séria ameaça. Atualmente, linhagens resistentes a pelo menos uma droga utilizada no tratamento da TB têm sido um dos principais fatores que impedem o controle efetivo da doença. De acordo com a OMS, linhagens multi-droga resistentes (MDR-TB) são aquelas resistentes a no mínimo isoniazida (H) e rifampicina (R), as principais drogas utilizadas no tratamento da TB. As principais mutações responsáveis por desenvolvimento de resistência à H e R acontecem principalmente em algumas regiões dos genes katG, inhA e rpoB, respectivamente. No presente estudo foi analisado o perfil de suscetibilidade de M. tuberculosis isolados de 132 pacientes atendidos em um hospital de referência em doenças infecciosas em Goiânia-Goiás, no período de janeiro de 2006 a julho de 2007. Foram coletados dados clínicos, epidemiológicos e utilizados testes de susceptibilidade à drogas, sequenciamento parcial dos genes katG e rpoB, análise de mutação por PCR do gene inhA e genotipagem por RFLP-IS6110. Foi observada uma alta frequência de resistência à drogas em pacientes virgens de tratamento (13,6% de resistência a no mínimo uma das droga testada e 6,1% de MDR-TB), e um alto grau de polimorfismo de DNA entre as linhagens resistentes. Estes resultados sugerem que a prevalência de linhagens resistentes na região está subestimada e que resistência aos antimicrobianos não está associada a um surto específico na região.
8

Molecular Diagnosis of TB and MDR-TB in HIV-Coinfection in Nigeria

Dinic, Lana January 2012 (has links)
Tuberculosis (TB) is the most common opportunistic infection in HIV-infected patients and the emergence of drug-resistant tuberculosis (DR-TB) is a growing problem in resource-limited settings (RLS). TB diagnosis in most RLS still depends on smear microscopy for acid-fast bacilli (AFB) while adequate infrastructure for testing drug sensitivity is unavailable. However, molecular diagnostics that detect Mycobacterium tuberculosis (Mtb) DNA and its genetic markers of drug resistance were recently developed. In this thesis I describe the use of a molecular diagnostic, Genotype MTBDRplus, for characterizing DR-TB and patterns of tuberculosis-like infection in two cities in south-west and north-central Nigeria. I found high rates of DR-TB in Nigerian HIV-infected individuals (9.3% for RIF or INH) with significantly different amounts by location (18.18% in south-west vs. 3.91% in north-central Nigeria, p=0.01). RIF resistance, indicative of MDR-TB, was found in 5.52% treatment-naïve patients, far exceeding the WHO predictions (0-4.3%). Furthermore, RIF resistance was genetically distinct, suggesting location-specific transmission of drug resistance (p=0.04). Genotype MTBDRplus correctly identified the drug-resistant samples compared to sequencing in 96.8% of cases. Mtb was confirmed in 56% of patients and was less likely to be found in patients on ART, while controlling for other relevant demographic characteristics (OR 0.29, P=0.02). Only abnormal respiratory findings on auscultation and the direct sputum smear grade greater than 3/100 were significant predictors of Mtb infection (OR 3.28, P=0.03; OR 6.40, p<0.01 respectively). Concentrated sputum smear was not significantly correlated with Mtb infection, except at the highest grades (>2+). Furthermore, in 49% of samples that were not confirmed for Mtb other actinomycetes were found: atypical Mycobacteria (ATM), Rhodococcus spp., Nocardia spp., Corynebacterium spp. I conclude that concentrated sputum AFB smears may misidentify bacteria as Mtb in a subset of HIV-infected patients. These individuals may have a different, even uncharacterized, actinomycete infection in the respiratory tract. Furthermore, total DR-TB in HIV-infection is high and transmission of DR-TB in HIV-infected patients in Nigeria is higher than estimated by the WHO. Molecular diagnostics are a rapid method for identifying Mtb and monitoring DR-TB, and can guide appropriate treatment decisions for respiratory infections in RLS with a high HIV burden.
9

Genotipagem e pesquisa de resistência fenotípica e genética à rifampicina e isoniazida em linhagens de Mycobacterium bovis isoladas de linfonodos de bovinos de abatedouro na região centro-oeste do estado de São Paulo

Franco, Marília Masello Junqueira. January 2016 (has links)
Orientador: Antonio Carlos Paes / Resumo: A tuberculose causada por Mycobacterium bovis (bTB) é uma zoonose de distribuição mundial com ampla gama de hospedeiros. Nos países onde a bTB é prevalente, 10 a 20% dos casos de tuberculose humana são causados por M. bovis. São escassos em todo o mundo estudos que investigam a resistência à isoniazida (INH) e rifampicina (RMP) em linhagens de M. bovis de origem bovina, reservatórios silvestres, e em casos humanos de tuberculose. Foi investigada a diversidade genotípica de 67 linhagens de M. bovis isoladas de bovinos de abatedouro, obtidas de 100 linfonodos com lesão caseosa, pelas técnicas de Spoligotyping e MIRU-VNTR, bem como foi determinado o perfil fenotípico de resistência à INH e RMP pela técnica de REMA, e pesquisadas possíveis bases genéticas para resistência aos antimicrobianos. Dentre os isolados, 11 (16%) foram classificados como MDR-TB, 8 (12%) resistentes à INH e 2 (3%) resistentes à RMP. A pesquisa pelo GenoType MTBDRplus ver. 2.0 não acusou a presença de mutações em nenhum dos isolados fenotipicamente resistentes. Foram identificados 16 spoligotipos entre as linhagens. A subfamília BOV_1 predominou com 52 (77,6%) isolados, com os SIT 481, 482, 594, 665, 691, 698, 1021, 1667, 1852, 2141 e dois isolados sem shared type. A BOV_2 foi identificada em 8 (11,9%) isolados, com o SIT 683. Os SIT 982, 1851 e 1853 foram agrupados na família BOV. Dois isolados não foram classificados em família ou subfamília. A análise de MIRU-VNTR com painel de 12 MIRUs, identificou 31 i... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Tuberculosis caused by Mycobacterium bovis (bTB) is a zoonosis of worldwide distribution with broad host range. In countries where bTB is prevalent, 10-20% of the human cases of tuberculosis are caused by M. bovis. All over the world there are few studies investigating the resistance to isoniazid (INH) and rifampicin (RMP) in M. bovis strains from cattle, wild reservoirs, and human cases of tuberculosis. The genotypic diversity of 67 M. bovis strains obtained out of 100 lymph nodes with caseous lesions from slaughtered animals was investigated by Spoligotyping and MIRU-VNTR techniques, as well as the assessment of their phenotypic profile of resistance to INH and RMP by REMA method and the search of possible genetic basis for antimicrobial resistance. Among the obtained isolates, 11 (16%) were classified as MDR-TB, 8 (12%) INH-resistant and 2 (3%) RMP-resistant. The use of GenoType MTBDRplus ver. 2.0 did not pointed the presence of genetic mutations in any of the phenotypically resistant isolates. Sixteen different spoligotype patterns were identified. The BOV_1 subfamily predominated with 52 (77.6%) isolates, with SITs 481, 482, 594, 665, 691, 698, 1021, 1667, 1852, 2141 and two isolates without a given SIT. BOV_2 was identified in 8 (11.9%) isolates, within SIT 683. The SITs 982, 1851 and 1853 were grouped in BOV family. Two isolates were not classified in family or subfamily. The MIRU-VNTR analysis using the 12 classical MIRUs, identified a cluster of 31 isolates belonging... (Complete abstract click electronic access below) / Doutor
10

The detection of drug resistant mutations in mycobacterium tuberculosis strains using anyplex MTB/NTM/MDR-TB plus assay in Limpopo Province

Mpanyane, Disego Mmatau January 2015 (has links)
Thesis (MSc. (Medical Sciences)) -- University of Limpopo, 2015 / Introduction: Multidrug-resistant tuberculosis (MDR-TB) caused by resistance to at least rifampicin (RIF) and isoniazid (INH) drugs is a growing public health concern in South Africa. The detection of MDR-TB still relies on culture despite advancement in molecular diagnostic technology. Currently MTBDRplus and GeneXpert are the only available assays used in rapid diagnosis of MDR-TB using chromosomal mutations in drug target regions. Some strains are missed by these assays due to their limitation in mutational detection profile. Novel Seegene Anyplex assays simultaneously detect TB and resistance to RIF and INH using fifteen and six mutational probes, respectively within 3 hours. Limpopo Province has limited information on the circulating strains of TB. Aim: To determine drug-resistant Mycobacterium tuberculosis (M. tuberculosis) mutations using Anyplex™ MTB/NTM/MDR-TB real time assay and characterise the drug-resistant strains. Methods: We prospectively collected 204 clinical samples at Modimolle MDR-TB unit and retrospectively used 104 culture isolates from MRC laboratory in Pretoria. The MTBDRplus assay was used to screen for M. tuberculosis and drug resistant mutations to RIF and INH drugs. Anyplex™ MTB/NTM/MDR-TB assay was used for rapid detection of M. tuberculosis and drug resistance to RIF and INH within 3 hours. The discordance between phenotypic and genotypic assays was resolved by sequencing and the Anyplex™ resistant profiles were spoligotyped. Diagnostic data was collected from NHLS and MRC databases and analysed using the Microsoft excel and Epi Info version 3.5. Descriptive statistics (percentages and frequencies) were used to explain proportions. Results: The Anyplex™ MTB/NTM assay detected M. tuberculosis in 69/111(62%) and 100/104 (96%) of clinical and culture samples respectively. The sensitivities, specificity, PPV and NPV obtained for both RIF and INH resistance by Anyplex™ MDR-TB assay were 67%, 59%, 67%, 55% and 15%, 100%, 100% and 17%, respectively. Anyplex™ MTB/NTM/MDR-TB resolved 23/45 (51%) of discordant vi samples. Sequencing of remaining discordant isolates revealed L511P, L533P and D516Y mutations within rpoB gene. A novel R385W mutation within katG was also detected. Spoligotyping of Anyplex™ MDR-TB resistant clinical isolates revealed Euro American clade with 20% followed by 15% Manu2, 5% East African Indian, 5% H37Rv, 5% atypical and 50% were orphans. Conclusion: The novel Anyplex™ MTB/NTM/MDR-TB assay is a rapid and valid technique for detecting M. tuberculosis and most common mutations conferring resistance to RIF and INH. However further investigations are required, as the assay has a lower sensitivity as compared to already endorsed techniques. / National Research Foundation (NRF) and University of Limpopo TB Grant

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