Decentralisation of the multidrug resistant tuberculosis (MDR TB) programme to primary health care (PHC) facilities in the Nelson Mandela Metropolitan was implemented in order to improve the effectiveness of MDR TB services. This study explored the knowledge gaps of nurses at PHC facilities as regards MDR TB. A quantitative, cross-sectional descriptive study was conducted; data was collected using a structured questionnaire. Non-probability sampling was applied in this study. A convenient sampling technique was used and 25 of the 42 facilities were selected. Thirty-two respondents completed the questionnaire with a response rate of 64%. Descriptive statistics were used to describe the data. Only 38% of the nurses had been trained on MDR TB. Overall scores were high with a mean knowledge score of 61%. However there were knowledge gaps regarding side effects of MDR TB medication. This study revealed gaps in knowledge of certain areas of MDR TB management / Health Studies / M.A. (Public Health)

Thesis (MScMedSc)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Central dogma suggests that mutations in target genes is the primary cause of resistance to first and second-line anti-TB drugs in Mycobacterium tuberculosis. However, it was previously reported that approximately 5% of Rifampicin mono-resistant clinical M. tuberculosis did not harbor mutations in the rpoB gene. The present study hypothesized that active efflux plays a contributory role in the level of intrinsic resistance to different anti-TB drugs (Isoniazid, Ethionamide, Pyrazinamide, Ethambutol, Ofloxacin, Moxifloxacin, Ciprofloxacin, Streptomycin, Amikacin and Capreomycin in RIF mono-resistant clinical M. tuberculosis isolates with a rpoB531 (Ser-Leu) mutation. This study aimed to define the role of Efflux pump inhibitors (verapamil, carbonylcyanide m-chlorophenylhydrazone and reserpine) in enhancing the susceptibility to different anti-TB drugs in the RIF mono-resistant clinical isolates. The isolates were characterized by determining the level of intrinsic resistance to structurally related/unrelated anti-TB drugs; determining the effect of EPIs on the level of intrinsic resistance in the isolates and comparing the synergistic properties of the combination of EPIs and anti-TB drugs. To achieve this, genetic characterization was done by PCR and DNA sequencing. Phenotyping was done by the MGIT 960 system EpiCenter software to determine the MICs of the different anti-TB drugs and the effect of verapamil and carbonylcyanide m-chlorophenylhydrazone on determined MICs. Due to inability to test reserpine in a MGIT, a different technique (broth microdilution) was used for the reserpine experiment. Additionally; fractional inhibitory concentrations (FIC) indices were calculated for each of these drugs. The FIC assess the anti-TB drugs/inhibitor interactions. STATISTICA Software: version 11 was used for statistical analysis. Results revealed that the RIF mono-resistant isolates were sensitive at the critical concentrations of all 10 drugs tested, with the exception of Pyrazinamide. This could be explained by the technical challenges of phenotypic Pyrazinamide testing. A significant growth inhibitory effect was observed between the combination of EPI and anti-TB drug exposure in vitro. This suggests that verapamil, carbonylcyanide m-chlorophenylhydrazone and reserpine play a significant role in restoring the susceptibility (decrease in intrinsic resistance level) of the RIF mono-resistant isolates to all anti-TB drugs under investigation. Additionally, a synergistic effect was observed by the combination treatment of the anti-TB drugs with the different EPIs. Based on these findings, we proposed a model suggesting that efflux pumps are activated by the presence of anti-TB drugs. The activated pumps extrude multiple or specific anti-TB drugs out of the cell, this in turn decrease the intracellular drug concentration, thereby causing resistance to various anti-TB drugs. In contrast, the addition of EPIs inhibits efflux pump activity, leading to an increase in the intracellular drug concentration and ultimate cell death. This is the first study to investigate the effect of different efflux pumps inhibitors on the level of intrinsic resistance to a broad spectrum of anti-TB drugs in drug resistant M. tuberculosis clinical isolates from different genetic backgrounds. The findings are of clinical significance as the combination of treatment with EPI and anti-TB drugs or use of EPIs as adjunctives could improve MDR-TB therapy outcome. / AFRIKAANSE OPSOMMING: Sentrale dogma beweer dat mutasies in teiken gene die primêre oorsaak van die weerstandheid teen anti-TB-middels in Mycobacterium tuberculosis is. Vorige studies het getoon dat ongeveer 5% van Rifampisien enkelweerstandige kliniese M. tuberculosis isolate nie ‘n mutasie in die rpoB geen het nie. Die hipotese van die huidige studie was dat aktiewe pompe 'n bydraende rol speel in die vlak van intrinsieke weerstandheid teen 10 verskillende anti-TB-middels (Isoniasied, Ethionamied, Pyrazinamied, Ethambutol, Ofloxacin, Moxifloxacin, Siprofloksasien, Streptomisien, Amikasien and Capreomycin) in RIF enkelweerstandige kliniese M . tuberculosis isolate met 'n rpoB531 (Ser-Leu) mutasie. Die doel van hierdie studie was om die rol van uitpomp inhibeerders (verapamil, carbonylcyanide m-chlorophenylhydrazone en reserpien) te definieer in die verbetering van die werking vir verskillende anti-TB-middels in die RIF enkelweerstandige kliniese isolate. Die doelstellings van die studie was om die vlak van intrinsieke weerstandigheid teen struktureel verwante/onverwante anti-tuberkulose middels asook die effek van die EPIs op die vlak van intrinsieke weerstand in die isolate is bepaal. Verder is sinergistiese eienskappe van die kombinasie van EPIs en anti-TB-middels ondersoek. Hierdie doelstellings is bereik deur genetiese karakterisering deur PKR en DNS volgorde bepaling. Fenotipering is gedoen deur gebruik te maak van MGIT 960 EpiCenter sagteware om die Minimum Inhibisie Konsentrasie (MIC) van die verskillende anti-TB-middels en die effek van verapamil en carbonylcyanide m-chlorophenylhydrazone op die MIC te bepaal. Reserpien kan nie in die MGIT sisteem getoets word nie, and daarom is 'n ander tegniek (mikro-verdunning) is gebruik om die effek van reserpien te toets. Fraksionele inhiberende konsentrasies (FIC) is bereken vir elk van hierdie middels die anti-TB-middels / inhibeerder interaksies te bepaal. STATISTICA v11 sagteware is gebruik vir alle statistiese analises. Resultate van hierdie studie toon dat die RIF enkelweerstandige isolate sensitief is teen kritieke konsentrasies van al die middels, met die uitsondering van Pyrazinamied. Weerstandigheid van Pyrazinamied kan wees as gevolg van welbekende tegniese probleme met die standaard fenotipiese pyrazinamied toets. ‘n Beduidende groei inhiberende effek is waargeneem tussen die kombinasie van EPI en anti-TB middel blootstelling in vitro. Dit dui daarop dat verapamil, CCCP en reserpine 'n belangrike rol speel in die herstel van die sensitiwiteit (afname in intrinsieke weerstand vlak) van die RIF enkelweerstandige isolate aan alle anti-TB-middels wat ondersoek is. Daarbenewens is 'n sinergistiese effek waargeneem deur die kombinasie van die verskillende anti-TB-middels en die verskillende EPIs. Op grond van hierdie bevindinge het ons ‘n model voorgestel wat toon dat uitvloei pompe geaktiveer word deur die teenwoordigheid van anti-TB-middels en die geaktiveerde pompe dan verskeie of spesifieke anti-TB-middels uit die sel pomp. Dus verminder die intrasellulêre konsentrasie van die middel en veroorsaak daardeur weerstandigheid teen verskeie anti-TB-middels. Die byvoeging van EPIs inhibeer uitvloei pompe se werking en lei tot 'n toename in die intrasellulêre konsentrasie van die middels en uiteindelik die dood van die selle. Hierdie is die eerste studie wat die effek van verskillende uitvloei pompe inhibeerders op die vlak van intrinsieke weerstand teen 'n breë spektrum van anti-TB-middels in die middel-weerstandige kliniese isolate ondersoek. Die bevindinge kan van belangrike kliniese belang wees aangesien die kombinasie van behandeling met EPI en anti-TB-middels die uitkoms MDR-TB terapie kan verbeter.

The purpose of the study was to investigate the problem of defaulting of tuberculosis (TB) treatment in the Khomas region of Namibia. A quantitative, descriptive research approach was used to investigate the reasons for defaulting of TB treatment under the DOTS strategy in Khomas Region of Namibia. Data was collected by using a structured interview schedule with 54 participants who were on DOTS strategy and defaulted. Data were analysed by using the Epi info computer program. The major findings from the data obtained, revealed that the respondents did not have an in-depth knowledge of TB and the health education was not successful. This contributed to the defaulting of their treatment. Based on the study findings nurses should improve health education to TB patients on DOTS and also educate members of the community to address the stigmatisation of TB. Recommendations for further improvement in the compliance of TB treatment were made. / Public Health / M.A. (Public Health)

Desde a primeira enzima ?-lactamase de espectro estendido (ESBL) detectada, na década de 1980, o número de diferentes enzimas ESBL têm aumentado exponencialmente. Houve também aumento no número de relatos de isolamento de bactérias resistentes presentes em alimentos de origem animal. O objetivo deste estudo foi avaliar enterobactérias de microbiota de frangos comerciais saudáveis, de granjas localizadas no interior do Estado de São Paulo (Brasil), quanto à resistência a antimicrobianos e ao potencial de virulência. Foram avaliadas todas as enterobactérias que apresentaram resistência à cefotaxima e/ou ceftazidima de 200 frangos comerciais para consumo humano. O teste de sensibilidade aos antimicrobianos foi realizado por disco de difusão para diferentes classes de antimicrobianos incluindo ?- lactâmicos e não ?-lactâmicos. Reação em cadeia da polimerase e sequenciamento foram utilizados para a pesquisa de genes codificadores de ESBL, ?-lactamases AmpC e determinantes de resistência às quinolonas mediada por plasmídeos (PMQR). A similaridade genética dos isolados foi caracterizada por eletroforese em campo pulsado (PFGE) e a localização cromossômica ou plasmideal de genes de resistência foi avaliada por I-Ceu IPFGE ou S1-PFGE. Além disso, experimentos de conjugação, tipagem de plasmídeos, investigação de filogenia e de virulência foram realizados. Em todas as amostras de cloaca coletadas foram identificados Enterobacteriaceae, incluindo Escherichia coli, Escherichia fergusonii, Klebsiella oxytoca e Klebsiella pneumoniae resistentes à cefotaxima e/ou ceftazidima. Salmonella sp não foi detectada. Foi encontrada ampla diversidade genômica entre todos os isolados classificados entre diferentes tipos de PFGE. Foram detectados diferentes genes codificadores de ?-lactamases, a maioria em diferentes plasmídeos, de diversos tamanhos, sendo alguns conjugativos, presentes em diferentes populações bacterianas. Foram identificados isolados de E. coli produtores de CTX-M-2, com inserção do gene blaCTX-M-2 no cromossomo bacteriano. Plasmídeo IncI (ST113/ST114) foi identificado carreando o gene blaCTX-M-8. Foram também encontrados os genes codificadores de ?- ii lactamase, blaCTX-M-2 e blaCTX-M-15, sendo carreados por plasmídeos. Foi identificado gene blaCMY-2 disseminado por plasmídeos de diferentes grupos de incompatibilidade, na população comensal de E. coli. Nos isolados que abrigavam gene PMQR, além das resistências às quinolonas, foi observado também resistência a outras importantes classes de antimicrobianos. Genes determinantes de PMQR abrigados em plasmídeos tipo ColE foram encontrados em E. coli, E. fergusonii, K. oxytoca e K. pneumoniae. Todas as aves comerciais de granjas localizadas no interior do Estado de São Paulo, incluídas nesse estudo, apresentaram isolados considerados multirresistentes a antimicrobianos e o trato intestinal destes frangos é reservatório dos genes de resistência em enterobactérias da microbiota normal. Além disso, alguns isolados demonstraram alto potencial de virulência, incluindo a capacidade de adesão e invasão em células epiteliais in vitro. / of commercial poultry in farms located at the countryside of São Paulo State (Brazil). All enterobacteria presenting cefotaxime and/or ceftazidime resistance from 200 commercial broiler chickens for human consumption were evaluated. Antimicrobial susceptibility testing was performed by disc diffusion for different classes of antimicrobials, including ?-lactams and non-?-lactams. The genes encoding ESBL, ampC ?-lactamases and determinants of plasmid mediated quinolone resistance (PMQR) were screened by polymerase chain reaction and sequencing. Genetic similarity of bacterial isolates was characterized by pulsed field gel electrophoresis (PFGE) and the location of the resistance genes in the chromosome or plasmids was evaluated by I-CeuI-PFGE or S1-PFGE. Additionally, experiments of conjugation, plasmid typing, phylogeny and virulence characterization were performed. Enterobacteriaceae were identified in all cloacal swab samples, including Escherichia coli, Escherichia fergusonii, Klebsiella oxytoca and Klebsiella pneumoniae resistant to cefotaxime and/or ceftazidime. Salmonella sp. was not detected. High genetic diversity was detected among all isolates, classified into diferent types of PFGE. Different genes coding for ?-lactamases were detected, harbored in diverse plasmids, of different sizes, some were conjugative and were present in different bacterial populations. E. coli isolates producing CTX-M-2 were identified, harbouring the blaCTX-M-2 gene inserted into the chromosome. IncI (ST113/ST114) plasmid was identified carrying the blaCTX-M-8 gene. The ?-lactamase coding genes, blaCTX-M-2 and blaCTX-M-15 were also found in plamids. The gene blaCMY-2 was found disseminated in different types of plasmid replicons in the commensal E. coli population. In isolates harbouring PMQR genes, in addition to the quinolones resistance, was observed resistance to other important antimicrobials classes was observed. PMQR determinant genes harbored in ColE-like plasmids were found in E. coli, E. fergusonii, K. oxytoca and K. pneumoniae. All commercial poultry from farms located at São Paulo State, evaluated in this study, carried isolates considered multidrug resistant and the intestinal tract of these chickens is reservoir of resistant genes blaCTX-M-2, blaCTX-M-8 and blaCTX-M-15 in enterobacteria from the normal microbiota. Moreover, some have demonstrated a high virulence potential, with adhesion and invasion capacity in epithelial cells cultured in vitro.

Enterococos são ubíquos no ambiente e fazem parte da microbiota do trato gastrintestinal de humanos e animais. A importância dessas bactérias tem sido associada com infecções hospitalares e resistência a múltiplas drogas, principalmente à vancomicina. O objetivo do presente estudo foi realizar a caracterização molecular de cepas de Enterococcus spp. resistentes à vancomicina (VRE) isoladas a partir de amostras coletadas de pacientes hospitalizados, água superficial de rios urbanos e carne de frango comercializada no Brasil. A presença do gene vanA foi confirmada em 20 cepas multirresitentes isoladas durante 1997-2011. Dentre os isolados VRE, 12 cepas foram identificadas como E. faecium e oito como E. faecalis. Cepas de E. faecium isoladas de amostras clínicas e águas foram classificadas como clonalmente relacionadas pelo PFGE, com perfil virulência predominante (acm+, esp+). Adicionalmente, enquanto cepas de E. faecium isoladas dos rios pertenceram aos ST203, ST412 e ST478 (previamente caracterizados como endêmicos em hospitais brasileiros), novos STs foram identificados entre as cepas de E. faecalis (ST614, ST615 e ST616) e E. faecium (ST953 e ST954) isoladas de alimentos. Sequências completas do transposon Tn1546 das cepas clínicas VREfm 320/07 (ST478) e ambiental VREfm 11 (ST412) mostraram Tn1546-like element de ~12800 pb, com um ponto de mutação no gene vanA na posição 7.698 (substituição do nucleotídeo T pelo C) e uma no gene vanX na posição 8.234 (G pelo T). Além disso, uma deleção na extremidade esquerda do Tn1546, e as sequências IS1251 e IS1216E na região intergênica vanHS e vanYX, respectivamente, também foram detectados. A este respeito, a IS1216E na região intergênica vanXY constitui um conjunto de genes previamente relatado em cepas clínicas de VREfm no Brasil, denotando uma característica regional. IS1216E tem sido associada com os genes tcrB e aadE que conferem resistência ao cobre e aminoglicosídeos, em E. faecium e Streptococcus agalactiae, respectivamente. Portanto, essa IS pode contribuir para a rápida aquisição de resistência antimicrobiana entre as espécies de cocos Gram-positivos clinicamente importantes. Os tipos de Tn1546 indistiguíveis que foram identificados no atual estudo isolados de humano e ambientes aquáticos sugerem uma comum partilha de um pool de genes de resistência à vancomicina. / Enterococci are ubiquitous in the environment and in the intestinal tract of humans and animals. The importance of these bacteria has been associated with nosocomial infection and multiple resistance to antimicrobial agents, mainly vancomycin. The aim of the present study was to perform molecular characterization of vancomycin-resistant Enterococcus spp. strains (VRE) isolated from hospitalized patients, surface water of urban rivers and retail chicken meat in Brazil. The presence of the vanA gene was confirmed in 20 multidrug-resistant strains isolated in 1997-2011. Among these VRE isolates, (n = 12) were identified as E. faecium and (n = 8) as E. faecalis. E. faecium strains isolated from water and clinical samples were classified as clonally related by PFGE, the predominant virulence profile being (acm+, esp+). Additionally, while E. faecium strains isolated from rivers belonging to ST203, ST412 and ST478 (previously characterized as endemic in Brazilian hospitals), new STs were identified among strains of E. faecalis (ST614, ST615 and ST616) and E. faecium (ST953 and ST954) isolated from food. Complete sequences of transposon Tn1546 from VREfm clinical strain 320/07 (ST478) and environmental strain VREfm 11 (ST412) showed a Tn1546-like element of ~12800 bp, with T7698C vanA and G8234T vanX mutations. Moreover, deletion of the Tn1546 left extremity, and the IS1251 and IS1216E sequence inside the vanHS and vanYX intergenic region, respectively, were also detected. In this regard, the IS1216E sequence inside the vanXY intergenic region constitutes a gene array previously reported for Brazilian VREfm clinical strains alone, denoting a regional characteristic. IS1216E has been associated with tcrB and aadE genes, which confer resistance to copper and aminoglycosides, in E. faecium and Streptococcus agalactiae, respectively. Therefore, IS1216E should contribute to rapid acquisition of antimicrobial resistance among species of the clinically important Gram-positive cocci. On the other hand, Tn1546-like elements were identical among clinical and environmental VREfm isolates, suggesting sharing of a common vancomycin resistance gene pool.

Thesis (M.Cur) --University of Limpopo, 2011 / The aim of this study was to determine the factors that contribute to the increase in the number of tuberculosis (TB) patients in Mpumalanga Province, and to develop guidelines and recommendations to address the challenges of this health issue. The design of the study was qualitative phenomenological. The population consisted of all TB patients who were receiving treatment either at the intensive or the continuation phase. The sampling method was purposive and the sample size comprised 20 participants, of whom 10 were drawn from Shatale clinic at Bushbuckridge, and 10 from Mashishing clinic at Thabachweu municipalities in the Ehlanzeni district of Mpumalanga Province. The data was gathered by means of semi-structured interviews. Data analysis was performed, from which themes and categories were derived. This study revealed several factors that contributed to the increase in the number of TB patients at the study sites. The factors considered most important in this study were the general lack of knowledge of TB among participants, despite their various levels of education, poverty, overcrowding, poor ventilation in the shacks and Reconstruction and Development Program (RDP) houses, unemployment, lack of support while taking treatment, religious and ritual beliefs, and the influence of traditional healers who dispense herbal medicines with the dictum that participants have been possessed by evil spirits and witches. The majority of patients developed TB as a secondary opportunistic infection because of their HIV-positive status, and lack of capacity to practice personal hygiene and proper infection control. Guidelines, strategies and recommendations were formulated to address these public health challenges in the context nursing education, research, administration and practice

<p>Many studies have reported low cure rates for multidrug-resistant tuberculosis (MDRTB) patients and MDR-TB patients co-infected with human immunodeficiency virus (HIV). However, little is&nbsp / known about the effect of HIV infection and antiretroviral therapy on the treatment outcomes of MDR-TB in South Africa. Therefore, the objectives of the study are: to find out whether HIV infection&nbsp / and interactions between ARVs and second line anti-TB drugs have an impact on the following MDR-TB treatment outcomes: cure rate and treatment failure at Brewelskloof Hospital. MDR-TB&nbsp / patients were treated for 18-24 months. The study was designed as a case-control retrospective study comparing MDR-TB treatment outcomes between HIV positive (cases) and HIV negative&nbsp / patients (controls). Patients were included in the study only if they complied with the following criteria: sensitivity to second line anti-TB drugs, MDR-TB infection, co-infection with HIV (for some&nbsp / of them), male and female patients, completion of treatment between 1 January 2006 and 31 December 2008. Any patients that presented with extreme drug-resistant tuberculosis (XDR-TB)&nbsp / were excluded from the study. Data were retrospectively collected from each patient&rsquo / s medical records. There were a total of 336 patients of which 242 (72%) were MDR-TB patients and 94&nbsp / (27.9%) MDRTB co-infected with HIV patients. Out of the 242 MDR-TB patients, 167 (69.2%) were males and 75 (30.7%) were females. Of the 94 patients with MDR-TB co-infected with HIV, 51&nbsp / (54.2%) males and 43 (45.7%) females. Patients with multidrug-resistant tuberculosis co-infected with HIV who qualify for antiretroviral therapy were treated with stavudine, lamivudine and&nbsp / efavirenz while all MDR-TB patients were given kanamycin, ethionamide, ofloxacin, cycloserine and pyrazinamide. The cure rate of MDR-TB in HIV (+) patients and in HIV (-) patients is 34.5%&nbsp / and 30 % respectively. There is no significant difference between both artes (pvalue = 0.80). The MDR-TB cure rate in HIV (+) patients taking antiretroviral drugs and in HIV (+) patients without&nbsp / antiretroviral therapy is 35% and 33% respectively. The difference between both rates is not statistically significant. The study shows that 65 (28.0%) patients completed MDR-TB treatment but&nbsp / could not be classified as cured or failure, 29 (12.5%) patients failed, 76 (32.7%) defaulted, 18 (7.7%) were transferred out and 44 (18.9%) died. As far as treatment completed and defaulted is concerned,&nbsp / there is no significant statistical difference between HIV (+) and HIV (-) The number of patients who failed the MDR-TB treatment and who were transferred out is significantly higher in the HIV (-)&nbsp / group than in the HIV (+) group. Finally the number of MDR-TB patients who died is significantly higher in the HIV (+) group). The median (range) duration of antiretroviral therapy before starting&nbsp / anti-tuberculosis drugs is 10.5 (1-60) months. According to this study results, the MDR-TB treatment cure rate at Brewelkloof hospital is similar to the cure rate at the national level. The study also&nbsp / hows that HIV infection and antiretroviral drugs do not influence any influence on MDR-TB treatment outcomes.</p>

<p>Many studies have reported low cure rates for multidrug-resistant tuberculosis (MDRTB) patients and MDR-TB patients co-infected with human immunodeficiency virus (HIV). However, little is&nbsp / known about the effect of HIV infection and antiretroviral therapy on the treatment outcomes of MDR-TB in South Africa. Therefore, the objectives of the study are: to find out whether HIV infection&nbsp / and interactions between ARVs and second line anti-TB drugs have an impact on the following MDR-TB treatment outcomes: cure rate and treatment failure at Brewelskloof Hospital. MDR-TB&nbsp / patients were treated for 18-24 months. The study was designed as a case-control retrospective study comparing MDR-TB treatment outcomes between HIV positive (cases) and HIV negative&nbsp / patients (controls). Patients were included in the study only if they complied with the following criteria: sensitivity to second line anti-TB drugs, MDR-TB infection, co-infection with HIV (for some&nbsp / of them), male and female patients, completion of treatment between 1 January 2006 and 31 December 2008. Any patients that presented with extreme drug-resistant tuberculosis (XDR-TB)&nbsp / were excluded from the study. Data were retrospectively collected from each patient&rsquo / s medical records. There were a total of 336 patients of which 242 (72%) were MDR-TB patients and 94&nbsp / (27.9%) MDRTB co-infected with HIV patients. Out of the 242 MDR-TB patients, 167 (69.2%) were males and 75 (30.7%) were females. Of the 94 patients with MDR-TB co-infected with HIV, 51&nbsp / (54.2%) males and 43 (45.7%) females. Patients with multidrug-resistant tuberculosis co-infected with HIV who qualify for antiretroviral therapy were treated with stavudine, lamivudine and&nbsp / efavirenz while all MDR-TB patients were given kanamycin, ethionamide, ofloxacin, cycloserine and pyrazinamide. The cure rate of MDR-TB in HIV (+) patients and in HIV (-) patients is 34.5%&nbsp / and 30 % respectively. There is no significant difference between both artes (pvalue = 0.80). The MDR-TB cure rate in HIV (+) patients taking antiretroviral drugs and in HIV (+) patients without&nbsp / antiretroviral therapy is 35% and 33% respectively. The difference between both rates is not statistically significant. The study shows that 65 (28.0%) patients completed MDR-TB treatment but&nbsp / could not be classified as cured or failure, 29 (12.5%) patients failed, 76 (32.7%) defaulted, 18 (7.7%) were transferred out and 44 (18.9%) died. As far as treatment completed and defaulted is concerned,&nbsp / there is no significant statistical difference between HIV (+) and HIV (-) The number of patients who failed the MDR-TB treatment and who were transferred out is significantly higher in the HIV (-)&nbsp / group than in the HIV (+) group. Finally the number of MDR-TB patients who died is significantly higher in the HIV (+) group). The median (range) duration of antiretroviral therapy before starting&nbsp / anti-tuberculosis drugs is 10.5 (1-60) months. According to this study results, the MDR-TB treatment cure rate at Brewelkloof hospital is similar to the cure rate at the national level. The study also&nbsp / hows that HIV infection and antiretroviral drugs do not influence any influence on MDR-TB treatment outcomes.</p>

Conventional drug susceptibility testing techniques, the ‘gold standard’ for M. tuberculosis are slow, requiring about 3-6 weeks from a positive culture. This diagnostic delay, before initiation of appropriate treatment, contributes to increased transmission rates. Molecular techniques provide rapid results and therefore present an alternative to conventional tests. The aim of this project was to develop an inhouse reverse line blot hybridization assay (RIFO assay) that could detect mutations associated with Rifampicin resistance directly in clinical specimens of patients in KwaZulu Natal. A 437 bp region of the rpoB gene was sequenced to ascertain the most frequently occurring mutations conferring resistance to rifampicin in isolates in KwaZulu-Natal. Wildtype and mutant probes designed to target these mutations, were immobilized on a Biodyne C membrane. Hybridization conditions were optimized using biotin labeled PCR products from culture. Detection was performed with peroxidase labeled streptavidin using enhanced chemiluminescence. Four DNA extraction methods were evaluated on sputum specimens to determine the one with the least inhibitory effect on amplification. A total of 11 mutations were found in 236 clinical isolates: 531TTG (109, 58.3%), 516GTC (26, 13%), 533CCG/516GGC (20, 10%), 533CCG (18, 9.6%), other mutations < 5% each. The chelex extraction method was found to be optimal for removing inhibitors in sputum specimens. Sputum specimens of 404 patients hospitalized at King George V Hospital between 2005 and 2006 were rifoligotyped. The RIFO assay was optimised on clinical isolates and then applied to sputum specimens. The RIFO assay on culture and sputum correlated well with the DST (sensitivity 92% and 94% respectively). However, the specificity was very low in both culture and sputum specimens compared to DST (38% and 35% respectively). This could be attributed to the presence of silent mutations, mixed infections, mixed populations of bacteria or the small number of susceptible strains used in this study. The in-house RIFO assay can be used directly on sputum specimens to predict Rifampicin resistance and therefore MDR-TB in less than a week compared to the gold standards. A total of 43 samples can be tested simultaneously at low cost and the membrane is reusable compared to commercial kits such as the Hains test that is expensive and strips are not reusable. A similar assay can be designed to target mutations for the detection of XDR-TB. Future studies should be conducted in a clinical setting on patients with sensitive strains to increase the specificity. / Thesis (M.Med.)-University of KwaZulu-Natal, Durban, 2011.

Mycobacterium tuberculosis (MTB) is an airborne pathogen that is easily transmitted from person to person. An intact immune system prevents the organism from causing disease in most individuals. In South Africa, the prevalence of human immunodeficiency virus (HIV) has reached astronomical levels and is now fuelling the tuberculosis (TB) epidemic. Drug resistant MTB strains combined with a weakened host immune system is a lethal combination. Multi-drug resistant (MDR) including extensively drug resistant (XDR) tuberculosis is on the increase, with Tugela Ferry in KwaZulu-Natal South Africa, reporting the largest cluster of XDR cases in the world. It is unknown whether a single clone of the drug resistant strain is circulating in this area or whether there are multiple strains at play. Using 2 complementary genotyping methods, we showed that the MDR strains present are the result of clonal spread associated with the F28 family, as well as de novo resistance which manifests as unique patterns. The XDR epidemic in Tugela Ferry is the result of clonal spread of a strain belonging to the F15/LAM4/KZN family. / Thesis (M.Med.)-University of KwaZulu-Natal, Durban, 2011.