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Background: Currently multidrug-resistant tuberculosis (MDR-TB) poses a signi cant public health concern in Malaysia.Objective: This study is aimed to evaluate the prevalence of MDR-TB in Malaysian tuberculosis patients. Method. A retrospective analysis was performed, and data was obtained from the Malaysian National TB Information System (TBIS) between 2009 and 2019. A record of 989 MDR-TB cases were identi ed and associated risk characteristics such as marital status, gender, ethnicity, employment status, alcohol consumption, diabetic status and smoking status were determined. The statistical analysis was performed using the SPSS software version 20.Results: Overall, the occurrence of MDR-TB among patients with TB infections in Malaysia was 0.34% based on data collected from TBIS. The ndings revealed major variations in the incidence of MDR-TB between male and female patients (0.44%, 0.20%, p < 0.001), single and married patients (1.63% vs 0.24%, p < 0.001), ethnicity (p < 0.001), working and non-working patients (0.48% vs 0.32%, p < 0.001), alcoholic and non-alcoholic patients (0.44% vs 0.32%, p < 0.001), diabetic patients and non-diabetic patients (0.39% vs 0.27%, p < 0.001), followed by smoking and non-smoking patients (0.13% vs 0.27%, p < 0.001). Conclusion:This study provides a substantial assessment of MDR-TB prevalence and associated risk factors that could be useful for the implementation of new strategies in Malaysia's national TB policy.

The main aim of this research is to investigate azole resistance mechanisms in Aspergillus fumigatus and Aspergillus niger which involve Cyp51A gene that encodes 14-α sterol demethylase enzyme. Methodology and results: Itraconazole susceptibility was determined through E-test method. A conventional PCR method was used to amplify and sequence Cyp51A gene in fungal DNA, to detect the presence of gene mutations. Real-time PCR method was applied to determine overexpression of Cyp51A gene in A. fumigatus and A. niger isolates. Susceptibility test found that 3/13 (23.1%) A. fumigatus and 7/23 (30.4%) A. niger isolates were resistant to itraconazole, with minimum inhibitory concentrations (MICs) of 2.5 µg/mL to 3.0 µg/mL. Sequencing of A. fumigatus DNA showed presence of L98H mutation in 7/13 (53.8%) and M220 mutation in 3/13 (23%) isolates. Whereas, sequencing of A. niger DNA detected the presence of G427S mutation in 3/23 (13%) isolates. Tandem Repeat mutation was not detected in all A. fumigatus and A. niger isolates. Only M220 mutation showed significant correlation (r(13)=0.041038, p< 0.05) with itraconazole antifungal resistance in A. fumigatus isolates while L98H mutation was not involved. G427S mutation also showed correlation (r(15)=0.038434, p< 0.05) with itraconazole antifungal resistance in A. niger isolates. A higher level of Cyp51A gene expression was detected in 4/8 (50%) A. fumigatus isolates and 7/10 (70%) A. niger isolates. Resistant isolates more often showed higher level of Cyp51A gene expression compared to susceptible isolates, however the difference in level of expression between resistant isolates and susceptible isolates is not significant. Conclusion, significance and impact of study: In conclusion the level of azole resistance in A. fumigatus and A. niger isolates in Malaysia is low and mutations in Cyp51A gene may contribute towards itraconazole antifungal resistance, however other factors may also be involved.

Aims: The main aim of this research is to investigate azole resistance mechanisms in A. fumigatus and A. niger which involve Cyp51A gene that encodes 14-α sterol demethylase enzyme. Methodology and results:Itraconazole susceptibility was determined through E-test method. A conventional PCR method was used to amplify and sequence Cyp51A gene in fungal DNA, to detect the presence of gene mutations. Real-time PCR method was applied to determine overexpression of Cyp51A gene in A. fumigatus and A. niger isolates. Susceptibility test found that 3/13 (23.1%) A. fumigatus and 7/23 (30.4%) A. niger isolates were resistant to Itraconazole, with minimum inhibitory concentrations (MICs) of 2.5 µg/ml to 3.0 µg/ml. Sequencing of A. fumigatus DNA showed presence of L98H mutation in 7/13 (53.8%) and M220 mutation in 3/13 (23%) isolates. Whereas, sequencing of A. niger DNA detected the presence of G427S mutation in 3/23 (13%) isolates. Tandem Repeat mutation was not detected in all A. fumigatus and A. niger isolates. Only M220 mutation showed significant correlation (r (13)=0.041038, p<0.05) with Itraconazole antifungal resistance in A. fumigatus isolates while L98H mutation was not involved. G427S mutation also showed correlation (r (15)=0.038434, p<0.05) with Itraconazole antifungal resistance in A. niger isolates. A higher level of Cyp51A gene expression was detected in 4/8 (50%) A. fumigatus isolates and 7/12 (58.3%) A. niger isolates. Resistant isolates more often showed higher level of Cyp51A gene expression compared to susceptible isolates; however the difference in level of expression between resistant isolates and susceptible isolates is not significant. This may be due to similar MIC values in resistant and susceptible isolates.Conclusion, significance and impact of study: In conclusion the level of azole resistance in A. fumigatus and A. niger isolates in Malaysia is low and mutations in Cyp51A gene may contribute towards Itraconazole antifungal resistance, however other factors may also be involved.