Clonal Spread of Highly β-Lactam-Resistant Streptococcus pneumoniae Isolates in Taiwan

ABSTRACT This study aimed to evaluate the antimicrobial susceptibility profiles of 364 Streptococcus pneumoniae isolates and studied the genotypes of S. pneumoniae with high level β-lactam resistance in Taiwan. Clonal complexes related to Spain23F-1, Taiwan19F-14, and Taiwan23F-15 were responsible for the spread of isolates with high β-lactam resistance.

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First data on antimicrobial susceptibility patterns of Moraxella catarrhalis isolates in Lebanon

The International Arabic Journal of Antimicrobial Agents ◽

10.3823/833 ◽

2019 ◽

Vol 9 (2) ◽

Author(s):

Monzer Hamze ◽

Marwan Osman ◽

Hassan Mallat ◽

Marcel El Achkar

Keyword(s):

Nalidixic Acid ◽

Antimicrobial Susceptibility ◽

Moraxella Catarrhalis ◽

Antibiotic Susceptibility ◽

Bacterial Pathogen ◽

Diagnostic Tools ◽

Flight Mass Spectrometry ◽

High Level ◽

Susceptibility Profiles ◽

Susceptibility Patterns

Background. Moraxella catarrhalis is an important bacterial pathogen. Although national data have shown an increase in the levels of antimicrobial resistance in clinical settings in Lebanon, there is a lack of data regarding this human pathogen. This study aimed to determine for the first time the antimicrobial susceptibility profiles of M. catarrhalis isolates in Lebanon. Methods. A total of 34 M. catarrhalis strains were isolated from clinical specimens during the period from November 2010 to March 2019. Bacterial identification was carried out using matrix assisted laser desorption ionization–time of flight mass spectrometry. Antibiotic susceptibility of all isolates was performed according the recommendations of the European Committee on Antimicrobial Susceptibility Testing (EUCAST). Results. A total of 34 non-duplicated M. catarrhalis strains were isolated from nose (n=19), ear (n=7), sputum (n=5), blood (n=1), eye (n=1), and throat (n=1) of patients referred to Nini Hospital in Tripoli, North governorate of Lebanon. Regarding antibiotic susceptibility rates, the percent susceptibility is 100% to the majority of antibiotics, except ampicillin (7.4%), trimethoprim-sulfamethoxazole (85.3%), nalidixic acid (85.3%), and ciprofloxacin (97.1%). Conclusion. To our knowledge, this study is the first investigation regarding the antimicrobial susceptibility patterns of M. catarrhalis isolates in Lebanon. In addition to the high level of resistance to ampicillin, our findings showed the emergence of resistance to trimethoprim-sulfamethoxazole, nalidixic acid and ciprofloxacin. Even if this study provides useful information to develop effective empirical treatment, we recommend the implementation of reliable diagnostic tools to guide appropriate treatment.

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Sparfloxacin Resistance in Clinical Isolates ofStreptococcus pneumoniae: Involvement of Multiple Mutations in gyrA and parC Genes

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.42.9.2193 ◽

1998 ◽

Vol 42 (9) ◽

pp. 2193-2196 ◽

Cited By ~ 28

Author(s):

Hideki Taba ◽

Nobuchika Kusano

Keyword(s):

Streptococcus Pneumoniae ◽

Amino Acid ◽

Antimicrobial Susceptibility ◽

Susceptibility Testing ◽

Clinical Isolates ◽

Amino Acid Substitutions ◽

Sequencing Analysis ◽

High Level ◽

Additional Nucleotide ◽

Level Resistance

ABSTRACT Antimicrobial susceptibility testing revealed among 150 clinical isolates of Streptococcus pneumoniae 4 pneumococcal isolates with resistance to fluoroquinolones (MIC of ciprofloxacin, ≥32 μg/ml; MIC of sparfloxacin, ≥16 μg/ml). Gene amplification and sequencing analysis of gyrA andparC revealed nucleotide changes leading to amino acid substitutions in both GyrA and ParC of all four fluoroquinolone-resistant isolates. In the case of strains 182 and 674 for which sparfloxacin MICs were 16 and 64 μg/ml, respectively, nucleotide changes were detected at codon 81 in gyrA and codon 79 in parC; these changes led to an Ser→Phe substitution in GyrA and an Ser→Phe substitution in ParC. Strains 354 and 252, for which sparfloxacin MICs were 128 μg/ml, revealed multiple mutations in both gyrA and parC. These strains exhibited nucleotide changes at codon 85 leading to a Glu→Lys substitution in GyrA, in addition to Ser-79→Tyr and Lys-137→Asn substitutions in ParC. Moreover, strain 252 showed additional nucleotide changes at codon 93, which led to a Trp→Arg substitution in GyrA. These results suggest that sparfloxacin resistance could be due to the multiple mutations in GyrA and ParC. However, it is possible that other yet unidentified mutations may also be involved in the high-level resistance to fluoroquinolones in S. pneumoniae.

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Antimicrobial susceptibility profiles of thermophilic campylobacters isolated from patients in the town of Nis

Vojnosanitetski pregled ◽

10.2298/vsp0907522m ◽

2009 ◽

Vol 66 (7) ◽

pp. 522-526 ◽

Cited By ~ 1

Author(s):

Biljana Miljkovic-Selimovic ◽

Tatjana Babic ◽

Branislava Kocic ◽

Ljiljana Ristic

Keyword(s):

Nalidixic Acid ◽

Antimicrobial Susceptibility ◽

Susceptibility Testing ◽

Dilution Method ◽

Agar Dilution Method ◽

Thermophilic Campylobacter ◽

Agar Dilution ◽

High Level ◽

Susceptibility Profiles ◽

The Town

Background/Aim. In some clinical forms of human Campylobacter infections, such as prolonged diarrhea or associated with postinfections sequels, antibacterial treatment is necessary. The aim of the present study was to evaluate the antimicrobial susceptibility of thermophilic Campylobacter strains isolated from patients with diarrhea, as well as from patients with diarrhea followed by postinfections sequels, to drugs used in the therapy of enterocolitis, and to nalidixic acid used in laboratory identification and differentiation of thermophilic Campylobacter spp. Methods. We studied the antimicrobial susceptibility profiles of 131 Campylobacter strains isolated from patients with diarrhea (122 strains), diarrhea associated with rheumatic disorders (8 strains), and one strain isolated from a patient with Guillain-Barr? Syndrome following Campylobacter enterocolitis. Susceptibility testing to erythromycin, gentamicin, tetracycline, chloramphenicol, ciprofloxacin and nalidixic acid was performed by the agar dilution method. Results. In the strains we investigated, resistance to gentamicin and chloramphenicol was not recorded, whereas a low rate of strains resistant to erythromycin (2.4%), a higher prevalence of strains resistant to tetracycline (9.9%), and a high level of resistance to ciprofloxacin (29.8%) and nalidixic acid (33.3%) were registered. All strains resistant to nalidixic acid were also resistant to ciprofloxacin. In addition, there was no difference in the occurrence of resistance between strains isolated from patients with diarrhea as compared to those isolated from patients with diarrhea followed by postinfection disorders. Conclusion. The fact that the most of Campylobacter strains were sensitive to erythromycin and all to gentamicin, makes erythromycin an antibiotic of choice in the treatment of Campylobacter diarrhea and gentamicin when parenteral therapy should be administered. Resistance to tetracycline and, especially, ciprofloxacin, necessitates antibiotic susceptibility testing.

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Evolution of Clonal and Susceptibility Profiles of Serotype 19A Streptococcus pneumoniae among Invasive Isolates from Children in Spain, 1990 to 2008

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01494-10 ◽

2011 ◽

Vol 55 (5) ◽

pp. 2297-2302 ◽

Cited By ~ 27

Author(s):

David Tarragó ◽

Lorenzo Aguilar ◽

Raquel García ◽

María-José Gimenez ◽

Juan-José Granizo ◽

...

Keyword(s):

Streptococcus Pneumoniae ◽

Invasive Disease ◽

Rapid Expansion ◽

Reference Laboratory ◽

Content Type ◽

Lineal Regression ◽

High Level ◽

Susceptibility Profiles ◽

Increasing Trends ◽

Sequence Types

ABSTRACTThe genetic structure and antibiotic nonsusceptibility of all serotype 19AStreptococcus pneumoniaepediatric pneumococcal isolates received at the Spanish Pneumococcal Reference Laboratory (1990 to 2008) were analyzed. Of them, 410 (79.8%) isolates belonged to 14 sequence types (STs) with >10 isolates each, and 104 to 73 STs (with 21 new STs, ST5141 to ST5161, with one isolate each). Time trends in 2000 to 2008 (n= 471) were explored by lineal regression. Serotype 19A increased from 5.7% in 2000 to 16.8% in 2008 (R2= 0.872;P= 0.001). Decreasing trends (P< 0.03) were found for ST202 (R2= 0.774) and ST81 (R2= 0.559), and increasing trends (P< 0.03) for ST878 (R2= 0.544) and ST320 (R2= 0.530), both belonging to the clonal complex (CC) Denmark14-32 and first detected in 2003 and 2007, respectively, and ST2013 (R2= 0.704) and ST4461 (R2= 0.707), both appearing in 2004. Penicillin nonsusceptibility was clustered in ST81, ST276, ST320, ST878, ST2013, and ST4461 (>90% nonsusceptibility), and amoxicillin and cefotaxime nonsusceptibility in ST320: 87% amoxicillin (MIC50/MIC90= 8/8 μg/ml) and 43.5% cefotaxime (MIC50/MIC90= 1/2 μg/ml) nonsusceptibility. No trends were found for erythromycin nonsusceptibility (ranging from 38.5% to 66.7%) and cefotaxime nonsusceptibility (ranging from 0.0% to 7.8%), but increasing trends (P< 0.02) were found for oral penicillin (from 16.7% in 2000 to 56.3% in 2008;R2= 0.628) and amoxicillin (from 0.0% before 2007 to 13.8% in 2008;R2= 0.628) nonsusceptibility. This study warns about the emergence of serotype 19A STs associated with high-level antibiotic nonsusceptibility, with a role for ST320 and ST878 occupying the niche left by some pneumococcal 7-valent conjugate vaccine (PCV7)-related resistant STs. The rapid expansion of serotype 19A and STs related to antibiotic resistance indicates that vaccines covering serotype 19A present advantages in countering invasive disease.

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Antimicrobial susceptibility profiles of bacterial isolates from intra-abdominal and skin and skin structure infections in Eastern and Western Europe

10.26226/morressier.56d6be7ad462b80296c97cb5 ◽

2016 ◽

Author(s):

Daniel Sahm

Keyword(s):

Antimicrobial Susceptibility ◽

Western Europe ◽

Bacterial Isolates ◽

Skin Structure ◽

Susceptibility Profiles ◽

Eastern And Western Europe

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Antimicrobial susceptibility profiles of Gram-negative bacilli isolated from patients with hepatobiliary infections in China: results from the study for monitoring antimicrobial resistance trends (SMART), 2006–2013

10.26226/morressier.56d5ba2cd462b80296c969c0 ◽

2016 ◽

Author(s):

Qiwen Yang

Keyword(s):

Antimicrobial Resistance ◽

Antimicrobial Susceptibility ◽

Gram Negative ◽

Susceptibility Profiles

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Factors Associated with Streptococcus pneumoniae Nasopharyngeal Carriage and Antimicrobial Susceptibility among Children Under the Age of 5 Years in the Southwestern Colombia

Journal of Pediatric Infectious Diseases ◽

10.1055/s-0041-1731343 ◽

2021 ◽

Author(s):

Gustavo Gámez ◽

Juan Pablo Rojas ◽

Santiago Cardona ◽

Juan David Castillo Noreña ◽

María Alejandra Palacio ◽

...

Keyword(s):

Streptococcus Pneumoniae ◽

Antimicrobial Susceptibility ◽

Indigenous Communities ◽

Cross Sectional Study ◽

Nasopharyngeal Swab ◽

Nasopharyngeal Carriage ◽

Cross Sectional ◽

Benzyl Penicillin ◽

Factors Associated ◽

Pediatric Outpatients

Abstract Objective This work aims to evaluate the factors associated with Streptococcus pneumoniae nasopharyngeal colonization and antimicrobial susceptibility among pediatric outpatients in southwestern Colombia, 2019. Methods A cross-sectional study was performed using survey-based interviews and the collection of nasopharyngeal-swab specimens for microbiological characterization and antimicrobial susceptibility testing. Logistic regression analyses were performed for factors associated with nasopharyngeal carriage. Results A total of 452 children under the age of 5 years were examined in which 41.8% carried S. pneumoniae. Higher pneumococcal carriage frequencies were observed among participants aged <2 years and in individuals belonging to indigenous communities, which were lacking established pneumococcal-conjugated vaccine-10 immunization schemes. Additionally, children attending childcare institutions were also highly colonized by pneumococci. S. pneumoniae showed 57.7% nonsusceptibility to benzyl-penicillin (meningitis-cut); 45.5% intermediate-sensitivity to benzyl-penicillin (oral-cut) and 21.7% to cefotaxime; and resistance to erythromycin (40.7%), tetracycline (36.0%), trimethoprim/sulfamethoxazole (24.9%), clindamycin (24.3%), and ceftriaxone (27.0%). Conclusion The 41.8% of participants carrying S. pneumoniae show a scenario with the presence of multidrug and extensively drug-resistant strains, which constitutes important reservoirs of bacterial transmission by children aged <5 years in Colombia, leading to an onset of pneumococcal diseases. Hence, there is an urgent need to expand conjugate pneumococcal immunization in the community and ensure compliance with established immunization schedules.

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Temporal Variations in Patterns of Clostridioides difficile Strain Diversity and Antibiotic Resistance in Thailand

Antibiotics ◽

10.3390/antibiotics10060714 ◽

2021 ◽

Vol 10 (6) ◽

pp. 714

Author(s):

Supapit Wongkuna ◽

Tavan Janvilisri ◽

Matthew Phanchana ◽

Phurt Harnvoravongchai ◽

Amornrat Aroonnual ◽

...

Keyword(s):

Antibiotic Resistance ◽

Antimicrobial Susceptibility ◽

Reference Strain ◽

Toxin Production ◽

Temporal Variations ◽

Toxin Gene ◽

Data Sets ◽

Clostridioides Difficile ◽

Life Threatening ◽

Susceptibility Profiles

Clostridioides difficile has been recognized as a life-threatening pathogen that causes enteric diseases, including antibiotic-associated diarrhea and pseudomembranous colitis. The severity of C. difficile infection (CDI) correlates with toxin production and antibiotic resistance of C. difficile. In Thailand, the data addressing ribotypes, toxigenic, and antimicrobial susceptibility profiles of this pathogen are scarce and some of these data sets are limited. In this study, two groups of C. difficile isolates in Thailand, including 50 isolates collected from 2006 to 2009 (THA group) and 26 isolates collected from 2010 to 2012 (THB group), were compared for toxin genes and ribotyping profiles. The production of toxins A and B were determined on the basis of toxin gene profiles. In addition, minimum inhibitory concentration of eight antibiotics were examined for all 76 C. difficile isolates. The isolates of the THA group were categorized into 27 A−B+CDT− (54%) and 23 A-B-CDT- (46%), while the THB isolates were classified into five toxigenic profiles, including six A+B+CDT+ (23%), two A+B+CDT− (8%), five A−B+CDT+ (19%), seven A−B+CDT− (27%), and six A−B−CDT− (23%). By visually comparing them to the references, only five ribotypes were identified among THA isolates, while 15 ribotypes were identified within THB isolates. Ribotype 017 was the most common in both groups. Interestingly, 18 unknown ribotyping patterns were identified. Among eight tcdA-positive isolates, three isolates showed significantly greater levels of toxin A than the reference strain. The levels of toxin B in 3 of 47 tcdB-positive isolates were significantly higher than that of the reference strain. Based on the antimicrobial susceptibility test, metronidazole showed potent efficiency against most isolates in both groups. However, high MIC values of cefoxitin (MICs 256 μg/mL) and chloramphenicol (MICs ≥ 64 μg/mL) were observed with most of the isolates. The other five antibiotics exhibited diverse MIC values among two groups of isolates. This work provides evidence of temporal changes in both C. difficile strains and patterns of antimicrobial resistance in Thailand.

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