Methods: The genomes of 24 MTBC isolated from sputum and pus samples were sequenced. The phenotypic drug susceptibility testing (DST) of the isolates was determined for ten anti-TB drugs. Bioinformatic analysis comprising genome assembly and annotation and single-nucleotide polymorphism (SNP) analysis in genes associated with resistance to the ten anti-TB drugs were done on each sequenced genome.
Results: The draft assemblies covered an average of 97% of the expected genome size. Eleven isolates were aligned to the Indo-Oceanic lineage, eight were East-Asian lineage, three were East African-Indian lineage, and one was of Euro-American and Bovis lineages, respectively. Twelve of the 24 MTBC isolates were phenotypically MDR M. tuberculosis: one is polyresistance and another one is monoresistance. Twenty-six SNPs across nine genes associated with resistance toward ten anti-TB drugs were detected where some of the mutations were found in isolates that were previously reported as pan-susceptible using DST. A haplotype consisting of 65 variants was also found among the MTBC isolates with drug-resistance traits.
Conclusions: This study is the first effort done in Malaysia to utilize 24 genomes of the local clinical MTBC isolates. The high-resolution molecular epidemiological data obtained provide valuable insights into the mechanistic and epidemiological qualities of TB within the vicinity of Southeast Asia.
OBJECTIVES: In the present study, an endophyte was isolated from the leaves of T. indica and screened for its antimicrobial potential.
METHODS: The selected endophyte was identified by 16s rRNA partial genome sequencing and investigated for their antimicrobial potency. The preliminary phytochemical tests were conducted for the affirmation of phytoconstituents in the endophytic crude ethyl acetate extract of T. indica (TIM) and total phenolic content was performed. The antimicrobial potential of TIM was evaluated against human pathogenic ATCC gram-positive and gram-negative bacterial strains.
RESULTS: TIM exhibited an appreciable amount of gallic acid equivalent phenolic content (21.6 ± 0.04 mg GAE/g of crude extract). TIM showed the Minimum Inhibitory Concentration (MIC) at 250 μg/mL and Minimum Bactericidal Concentration (MBC) at 500 μg/mL among the selected human pathogenic ATCC strains. At MIC of 500 μg/mL, TIM displayed a significant zone of inhibition against P. aeruginosa and N. gonorrhoeae.
CONCLUSION: The results from our study highlighted for the first time the antimicrobial potential of endophytic bacterial strain Bacillus velezensis in T. indica leaves and it could be further explored as a source of natural antimicrobial agents.
METHOD: Cross-sectional study performed in the Chattogram Medical College Hospital, Bangladesh. Mueller Hinton agar plates were used for antibiotic sensitivity testing by the Kirby-Buer disc diffusion test.
RESULTS: Among 105 clinically suspected VAP cases, qualitative cultures were positive in 95 (90%) of them. The most common bacteria identified were Acinetobacter spp. (43.2%), Klebsiella spp. (20%) and Pseudomonas spp. (18.9%). A positive culture was not associated with patients' age or gender. Among 41 isolated Acinetobacter spp., 38 (92.7%) were resistant to gentamicin followed by 36 (87.8%) to ceftriaxone. Among 24 isolated Klebsiella spp., 22 (83.3%) were resistant to ceftriaxone. Among 18 isolated Pseudomonas spp., 16 (88.8%) were resistant to ciprofloxacin, and 13 (72.2%) were resistant to ceftriaxone. Among nine isolated E.coli, all were resistant to ceftriaxone and ciprofloxacin. All four Proteus spp. (100%) isolated were resistant to ciprofloxacin. Additionally, phenotype MBL producing was 65.22% and genotype was 45.65% among imipenem resistant pathogens. Imipenem resistant pathogens were sensitive to amoxyclav, amikacin¸ azithromycin, ceftazidime, ceftriaxone, colistin and gentamycin.
CONCLUSION: A positive culture was detected in 90% of VAP patients, but it was not associated with the patients' age and gender. The most common bacteria identified were Acinetobacter spp., Klebsiella spp. and Pseudomonas spp., where the majority of these were resistant to ceftriaxone. The results are being used to provide future guidance on the empiric management of VAP in this hospital.
METHODS: CLSI broth microdilution methodology was used to determine antimicrobial activity and EUCAST breakpoints version 9.0 were used to determine rates of susceptibility and resistance. Isolates were also screened for the genes encoding extended-spectrum β-lactamases (ESBLs) or carbapenemases (including metallo-β-lactamases [MBLs]).
RESULTS: Between 2015 and 2017, this study collected a total of 7051 Enterobacterales isolates and 2032 Pseudomonas aeruginosa isolates from hospitalized patients in Australia, Japan, South Korea, Malaysia, the Philippines, Taiwan, and Thailand. In the Asia-Pacific region, Enterobacterales isolates that were ESBL-positive, carbapenemase-negative (17.9%) were more frequently identified than isolates that were carbapenemase-positive, MBL-negative (0.7%) or carbapenemase-positive, MBL-positive (1.7%). Multidrug-resistant (MDR) isolates of P. aeruginosa were more commonly identified (23.4%) than isolates that were ESBL-positive, carbapenemase-negative (0.4%), or carbapenemase-positive, MBL-negative (0.3%), or carbapenemase-positive, MBL-positive (3.7%). More than 90% of all Enterobacterales isolates, including the ESBL-positive, carbapenemase-negative subset and the carbapenemase-positive, MBL-negative subset, were susceptible to amikacin and ceftazidime-avibactam. Among the carbapenemase-positive, MBL-positive subset of Enterobacterales, susceptibility to the majority of agents was reduced, with the exception of colistin (93.4%). Tigecycline was active against all resistant subsets of the Enterobacterales (MIC90, 1-4 mg/L) and among Escherichia coli isolates, > 90% from each resistant subset were susceptible to tigecycline. More than 99% of all P. aeruginosa isolates, including MDR isolates and the carbapenemase-positive, MBL-positive subset, were susceptible to colistin.
CONCLUSIONS: In this study, amikacin, ceftazidime-avibactam, colistin and tigecycline appear to be potential treatment options for infections caused by Gram-negative pathogens in the Asia-Pacific region.
METHODS: Growth inhibitory indices and fractional inhibitory concentration index were applied to evaluate the in vitro synergistic activity of phytoextract-antibiotic combinations in general.
FINDINGS: A number of studies have indicated that plant-derived natural compounds are capable of significantly reducing the minimum inhibitory concentration of standard antibiotics by altering drug-resistance mechanisms of B. anthracis and other superbug infection causing bacteria. Phytochemical compounds allicin, oleanolic acid, epigallocatechin gallate and curcumin and Jatropha curcas extracts were exceptional synergistic potentiators of various standard antibiotics.
CONCLUSION: Considering these facts, phytochemicals represents a valuable and novel source of bioactive compounds with potent antibiotic synergism to modulate bacterial drug-resistance.