Fluoroquinolone Resistance amongMycobacterium tuberculosisStrains from Karachi, Pakistan: Data from Community-Based Field Clinics

ABSTRACTA fluoroquinolone (FQ) resistance rate of 5.9% is reported in 205Mycobacterium tuberculosisisolates from patients presenting to field clinics in Karachi, Pakistan (2006 to 2009). FQ resistance among multidrug-resistant (MDR) strains was 11.1% (5/45), and it was 4.9% (5/103) inM. tuberculosisstrains susceptible to all first-line agents. Spoligotyping of resistant strains did not show dominance of one strain type. Our data reflect considerable FQ-resistantM. tuberculosisisolates and the need to consider inclusion of FQ within first-line sensitivity testing in such settings.

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Prevalence of Fluoroquinolone Resistance among Tuberculosis Patients in Shanghai, China

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00177-09 ◽

2009 ◽

Vol 53 (7) ◽

pp. 3170-3172 ◽

Cited By ~ 31

Author(s):

Peng Xu ◽

Xia Li ◽

Ming Zhao ◽

Xiaohong Gui ◽

Kathryn DeRiemer ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Molecular Marker ◽

Pulmonary Tuberculosis ◽

Multidrug Resistant ◽

Tuberculosis Treatment ◽

Fluoroquinolone Resistance ◽

First Line ◽

Tuberculosis Patients ◽

Resistant Strains ◽

Line Drug

ABSTRACT We determined the prevalence of fluoroquinolone resistance among the isolates of Mycobacterium tuberculosis from 605 pulmonary tuberculosis patients in Shanghai, China. Mutations in gyrA were found in 81.5% of phenotypically fluoroquinolone-resistant isolates and were used as a molecular marker of fluoroquinolone resistance. gyrA mutations were detected in 1.9% of strains pan-susceptible to first-line drugs and 25.1% of multidrug-resistant strains. Fluoroquinolone resistance was independently associated with resistance to at least one first-line drug and prior tuberculosis treatment.

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In Vitro Activity of Tedizolid against Mycobacterium tuberculosis

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01939-18 ◽

2019 ◽

Vol 63 (4) ◽

Cited By ~ 3

Author(s):

Pilar Ruiz ◽

Manuel Causse ◽

Manuel Vaquero ◽

Manuel Casal

Keyword(s):

Mycobacterium Tuberculosis ◽

Multidrug Resistant ◽

Vitro Activity ◽

In Vitro Activity ◽

First Line ◽

Gram Positive ◽

Content Type ◽

Resistant Strains

ABSTRACT Tedizolid is a novel oxazolidinone with activities against Gram-positive microorganisms, including mycobacteria. We studied the in vitro activity of tedizolid against 120 Mycobacterium tuberculosis strains, including susceptible, first-line-resistant, and multidrug-resistant isolates. MIC was tested using the Bactec 960 MGIT system. MIC90 and MIC50 were 0.5 and 0.25 μg/ml, respectively, in susceptible and resistant strains. Tedizolid may be an alternative in the treatment of resistant M. tuberculosis.

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Three-Year Trend in Escherichia coli Antimicrobial Resistance among Children’s Urine Cultures in an Italian Metropolitan Area

Children ◽

10.3390/children8070597 ◽

2021 ◽

Vol 8 (7) ◽

pp. 597

Author(s):

Luca Pierantoni ◽

Laura Andreozzi ◽

Simone Ambretti ◽

Arianna Dondi ◽

Carlotta Biagi ◽

...

Keyword(s):

Escherichia Coli ◽

Metropolitan Area ◽

Bacterial Infections ◽

Asymptomatic Bacteriuria ◽

Multidrug Resistant ◽

Resistance Rate ◽

First Line ◽

E Coli ◽

First Line Therapy ◽

Tract Infections

Urinary tract infections (UTIs) are among the most common bacterial infections in children, and Escherichia coli is the main pathogen responsible. Several guidelines, including the recently updated Italian guidelines, recommend amoxicillin-clavulanic acid (AMC) as a first-line antibiotic therapy in children with febrile UTIs. Given the current increasing rates of antibiotic resistance worldwide, this study aimed to investigate the three-year trend in the resistance rate of E. coli isolated from pediatric urine cultures (UCs) in a metropolitan area of northern Italy. We conducted a retrospective review of E. coli-positive, non-repetitive UCs collected in children aged from 1 month to 14 years, regardless of a diagnosis of UTI, catheter colonization, urine contamination, or asymptomatic bacteriuria. During the study period, the rate of resistance to AMC significantly increased from 17.6% to 40.2% (p < 0.001). Ciprofloxacin doubled its resistance rate from 9.1% to 16.3% (p = 0.007). The prevalence of multidrug-resistant E. coli rose from 3.9% to 9.2% (p = 0.015). The rate of resistance to other considered antibiotics remained stable, as did the prevalence of extended spectrum beta-lactamases and extensively resistant E. coli among isolates. These findings call into question the use of AMC as a first-line therapy for pediatric UTIs in our population, despite the indications of recent Italian guidelines.

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Why Phenotypic Drug Susceptibility Testing of Mycobacterium tuberculosis to First-Line Drugs is not Sufficient for Proper Management of Drug-Resistant and Multidrug-Resistant tuberculosis?

Journal of Bacteriology & Parasitology ◽

10.4172/2155-9597.1000e128 ◽

2017 ◽

Vol 09 (01) ◽

Author(s):

Suhail Ahmad

Keyword(s):

Mycobacterium Tuberculosis ◽

Susceptibility Testing ◽

Drug Susceptibility ◽

Multidrug Resistant ◽

Drug Susceptibility Testing ◽

Drug Resistant ◽

First Line ◽

Proper Management ◽

Resistant Tuberculosis ◽

Multidrug Resistant Tuberculosis

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Constraints of Drug Resistance in Mycobacterium tuberculosis - Prospects for Pharmacological Reversion of Susceptibility to Antibiotics

The Open Conference Proceedings Journal ◽

10.2174/2210289201708010033 ◽

2017 ◽

Vol 8 (1) ◽

pp. 33-43 ◽

Cited By ~ 2

Author(s):

Aleksandr I. Ilin ◽

Murat E. Kulmanov ◽

Ilya S. Korotetskiy ◽

Marina V. Lankina ◽

Gulshara K. Akhmetova ◽

...

Keyword(s):

Clinical Trial ◽

Drug Resistance ◽

Mycobacterium Tuberculosis ◽

Genetic Heterogeneity ◽

Multidrug Resistant ◽

Resistance Mutations ◽

General Increase ◽

Drug Induced ◽

Mdr Tb ◽

Resistant Strains

Emergence of multidrug resistant strains ofMycobacterium tuberculosis(MDR-TB) threatens humanity. This problem was complicated by the crisis in development of new anti-tuberculosis antibiotics. Induced reversion of drug resistance seems promising to overcome the problem. Successful clinical trial of a new anti-tuberculosis nanomolecular complex FS-1 has demonstrated prospectively of this approach in combating MDR-TB. Several clinical MDR-TB cultures were isolated from sputum samples prior and in the process of the clinical trial. Every isolate was tested for susceptibility to antibiotics and then they were sequenced for comparative genomics. It was found that the treatment with FS-1 caused an increase in the number of antibiotic susceptible strains among Mtb isolates that was associated with a general increase of genetic heterogeneity of the isolates. Observed impairing of phthiocerol dimycocerosate biosynthesis by disruptive mutations inppsACDsubunits indicated a possible virulence remission for the sake of persistence. It was hypothesized that the FS-1 treatment eradicated the most drug resistant Mtb variants from the population by aggravating the fitness cost of drug resistance mutations. Analysis of distribution of these mutations in the global Mtb population revealed that many of them were incompatible with each other and dependent on allelic states of many other polymorphic loci. The latter discovery may explain the negative correlation between the genetic heterogeneity of the population and the level of drug tolerance. To the best of our knowledge, this work was the first experimental confirmation of the drug induced antibiotic resistance reversion by the induced synergy mechanism that previously was predicted theoretically.

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Prevalence of primary drug resistant tuberculosis in a tertiary care hospital, Nepal

Journal of Chitwan Medical College ◽

10.3126/jcmc.v4i4.11970 ◽

2015 ◽

Vol 4 (4) ◽

pp. 36-38

Author(s):

R Khunjeli ◽

U R Mohsin ◽

S K Shrestha ◽

S Adhikari ◽

B Srivastava ◽

...

Keyword(s):

Armed Forces ◽

Care Hospital ◽

Drug Resistant ◽

Newly Diagnosed ◽

First Line ◽

Sensitivity Testing ◽

Drug Resistant Tuberculosis ◽

Resistant Tuberculosis ◽

Resistant Strains ◽

Primary Drug

Background & objectives: Tuberculosis is a transmissible disease mainly due to inhalation of infected droplet nuclei. The burden of drug resistant tuberculosis is very high in our neighboring countries India and China. Prevalence of primary drug resistant disease is difficult to estimate in our country because culture and sensitivity is not done routinely. This study was an attempt to find out the prevalence of drug resistant in newly diagnosed tuberculosis patients serving in the Nepalese Armed Forces. Methodology: Medical records of patients serving in the Nepalese Armed Forces who had the provisional diagnosis of pulmonary tuberculosis for the first time from July 2012 to June 2014 were analyzed. They had their sputum subjected for both smear and culture with sensitivity testing. Out of 134 patients, 62 had culture positive for Mycobacterium tuberculosis and drug sensitivity was done for the first line 4 antitubercular drugs. Results: Drug resistant strains were found in 5 cases (8.1%) of which 2 (3.2%) were resistant to 4 first line drugs - rifampicin, isoniazid, ethambutol and streptomycin. Prevalence of isoniazid resistance was the highest, found in 3 cases (4.8%). Conclusion: Primary drug resistant tuberculosis in newly diagnosed cases was high even in young healthy adults, and isoniazid resistant strains were the commonest.DOI: http://dx.doi.org/10.3126/jcmc.v4i4.11970

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Mechanisms of first-line antimicrobial resistance in multi-drug and extensively drug resistant strains of Mycobacterium tuberculosis in KwaZulu-Natal, South Africa

BMC Infectious Diseases ◽

10.1186/s12879-016-1906-3 ◽

2016 ◽

Vol 16 (1) ◽

Cited By ~ 6

Author(s):

Navisha Dookie ◽

A. Willem Sturm ◽

Prashini Moodley

Keyword(s):

South Africa ◽

Mycobacterium Tuberculosis ◽

Antimicrobial Resistance ◽

Drug Resistant ◽

First Line ◽

Extensively Drug Resistant ◽

Kwazulu Natal ◽

Resistant Strains ◽

Drug Resistant Strains

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Cockroaches as a Source of High Bacterial Pathogens with Multidrug Resistant Strains in Gondar Town, Ethiopia

BioMed Research International ◽

10.1155/2016/2825056 ◽

2016 ◽

Vol 2016 ◽

pp. 1-6 ◽

Cited By ~ 13

Author(s):

Feleke Moges ◽

Setegn Eshetie ◽

Mengistu Endris ◽

Kahsay Huruy ◽

Dagnachew Muluye ◽

...

Keyword(s):

Bacterial Infections ◽

Bacterial Species ◽

Multidrug Resistant ◽

Resistance Rate ◽

Control Measures ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Gondar Town ◽

Resistant Strains ◽

And Control

Background. Cockroaches are source of bacterial infections and this study was aimed to assess bacterial isolates and their antimicrobial profiles from cockroaches in Gondar town, Ethiopia.Methods. A total of 60 cockroaches were collected from March 1 to May 30, 2014, in Gondar town. Bacterial species were isolated from external and internal parts of cockroaches. Disk diffusion method was used to determine antibiotic susceptibility patterns. Data were entered and analyzed by using SPSS version 20;Pvalues <0.005 were considered as statistically significant.Results. Of 181 identified bacteria species, 110 (60.8%) and 71 (39.2%) were identified from external and internal parts of cockroaches, respectively.Klebsiella pneumoniae32 (17.7%),Escherichia coli29 (16%), andCitrobacterspp. 27 (15%) were the predominant isolates. High resistance rate was observed to cotrimoxazole, 60 (33.1%), and least resistance rate was noted to ciprofloxacin, 2 (1.1%). Additionally, 116 (64.1%) of the isolates were MDR strains;Salmonellaspp. were the leading MDR isolates (100%) followed byEnterobacter(90.5%) andShigellaspp. (76.9%).Conclusion. Cockroaches are the potential source of bacteria pathogens with multidrug resistant strains and hence effective preventive and control measures are required to minimize cockroach related infections.

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Direct Detection of Pyrazinamide Resistance in Mycobacterium tuberculosis by Use of pncA PCR Sequencing

Journal of Clinical Microbiology ◽

10.1128/jcm.00145-19 ◽

2019 ◽

Vol 57 (8) ◽

Author(s):

Kingsley King-Gee Tam ◽

Kenneth Siu-Sing Leung ◽

Gilman Kit-Hang Siu ◽

Kwok-Chiu Chang ◽

Samson Sai-Yin Wong ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Direct Detection ◽

Drug Susceptibility ◽

Multidrug Resistant ◽

Activity Data ◽

Content Type ◽

Treatment Regimens ◽

Mdr Tb ◽

Resistant Strains ◽

Respiratory Specimens

ABSTRACT An in-house-developed pncA sequencing assay for analysis of pyrazinamide (PZA) resistance was evaluated using 162 archived Mycobacterium tuberculosis complex (MTBC) isolates with phenotypic PZA susceptibility profiles that were well defined by analysis of Bactec MGIT 960 PZA kit and PZase activity data. Preliminary results showed 100% concordance between pncA sequencing and phenotypic PZA drug susceptibility test (DST) results among archived isolates. Also, 637 respiratory specimens were prospectively collected, and 158 were reported as MTBC positive by the Abbott Realtime MTB assay (96.3% sensitivity [95% confidence interval {CI}: 92.2% to 98.7%]; 100% specificity [95% CI: 99.2% to 100.0%]). Genotypic and phenotypic PZA resistance profiles of these 158 MTBC-positive specimens were analyzed by pncA sequencing and Bactec MGIT 960 PZA kit, respectively. For analysis of PZA resistance, pncA sequencing detected pncA mutations in 5/5 (100%) phenotypic PZA-resistant respiratory specimens within 4 working days. No pncA mutations were detected among PZA-susceptible specimens. Combining archived isolates with prospective specimens, 27 were identified as phenotypic PZA resistant with pncA mutation. Among these 27 samples, 6/27 (22.2%) phenotypic PZA-resistant strains carried novel pncA mutations without rpsA and panD mutations. These included 5 with mutations (a deletion [Del] at 383T [Del383T], Del 380 to 390, insertion of A [A Ins] at position 127, A Ins at position 407, and G Ins at position 508) in pncA structural genes and 1 with a mutation (T-12C) at the pncA promoter region. All six of these strains had no or reduced PZase activities, indicating that the novel mutations might confer PZA resistance. Additionally, 25/27 phenotypic PZA-resistant strains were confirmed multidrug-resistant tuberculosis (MDR-TB) strains. As PZA is commonly used in MDR-TB treatment regimens, direct pncA sequencing will rapidly detect PZA resistance and facilitate judicious use of PZA in treating PZA-susceptible MDR-TB.

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