Molecular Characterization and Moxifloxacin Susceptibility of Clostridium difficile

In recent years, the incidence and severity of Clostridium difficile infections has increased.Additionally, resistance of C. difficile to frequently used antibiotics is rising. To improve ourunderstanding of C. difficile, there is a need for molecular characterization of different strains andantibiotic resistance testing. We investigated the efficacy of GenoType CDiff kit (Hain Lifesciences)in identification of C. difficile and its various strains in northern Israel. The kit involves a molecularassay that detects C. difficile from stool samples or colonies and identifies the different strains andmutations in the gyrA gene that cause moxifloxacin resistance. Forty‐nine C. difficile positive sampleswere examined by the kit following DNA extraction from both colonies and stool. The identificationrate (95.9%) of C. difficile was much higher when DNA was extracted from colonies, compared toextraction from stool (46.9%). Low frequencies of ribotype027 strain (2%) and of ribotype078 strain(4%) were found. There was a high concordance between genotype (mutation in gyrA) andphenotype (Etest) for moxifloxacin resistance (Kappa=0.72). A high percentage of moxifloxacinresistantstrains was found. Our findings indicate that the GenoType CDiff kit is very effective incharacterization of C. difficile strains and less effective for identification of C. difficile directly fromstool samples.

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Molecular Characterization of Giardia duodenalis in Children and Adults Sampled in Algeria

Microorganisms ◽

10.3390/microorganisms9010054 ◽

2020 ◽

Vol 9 (1) ◽

pp. 54

Author(s):

Salem Belkessa ◽

Daniel Thomas-Lopez ◽

Karim Houali ◽

Farida Ghalmi ◽

Christen Rune Stensvold

Keyword(s):

Real Time ◽

Molecular Characterization ◽

Real Time Pcr ◽

Intestinal Parasites ◽

Giardia Duodenalis ◽

Specific Pcr ◽

Stool Samples ◽

Pcr Targeting ◽

Assemblage B

The molecular epidemiology of giardiasis in Africa remains unclear. A study was carried out across four hospitals in Algeria. A total of 119 fecal samples from 55 children, 37 adults, and 27 individuals of undetermined age, all scored positive for intestinal parasites by microscopy, and were screened by real-time PCR for Giardia. Molecular characterization of Giardia was performed by assemblage-specific PCR and PCR targeting the triose phosphate isomerase gene (tpi). Of the 119 samples, 80 (67%) were Giardia-positive by real-time PCR. For 48 moderately-highly real-time PCR-positive samples, tpi genotyping assigned 22 samples to Assemblage A and 26 to Assemblage B. Contrary to Assemblage A, Assemblage B exhibited substantial genetic diversity and allelic heterozygosity. Assemblage-specific PCR proved to be specific for discriminating Assemblage A or B but not as sensitive as tpi genotyping. We confirmed that real-time PCR is more sensitive than microscopy for detecting Giardia in stool samples and that robust amplification and sequencing of the tpi gene is feasible when moderate-to-strongly real-time PCR-positive samples are used. This study is one of the few performed in Africa providing genotyping data on Giardia infections in humans. Both assemblages A and B were commonly seen and not associated with specific sociodemographic data.

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Multiplex Real-Time PCR Method for Simultaneous Identification and Toxigenic Type Characterization of Clostridium difficile From Stool Samples

Annals of Laboratory Medicine ◽

10.3343/alm.2015.35.3.306 ◽

2015 ◽

Vol 35 (3) ◽

pp. 306-313 ◽

Cited By ~ 10

Author(s):

Abdullah Kilic ◽

Mohammad J. Alam ◽

Naradah L. Tisdel ◽

Dhara N. Shah ◽

Mehmet Yapar ◽

...

Keyword(s):

Clostridium Difficile ◽

Real Time ◽

Real Time Pcr ◽

Stool Samples ◽

Pcr Method ◽

Simultaneous Identification

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Molecular characterization of hookworm spp. isolated from food handlers, Khartoum, Sudan: A cross-sectional study

F1000Research ◽

10.12688/f1000research.14683.1 ◽

2018 ◽

Vol 7 ◽

pp. 662

Author(s):

Tarig A. Gamar ◽

Hassan H. Musa ◽

Hisham N. Altayb ◽

Mohamed H. Mohamed ◽

Adam D. Abakar

Keyword(s):

Public Health ◽

Molecular Characterization ◽

Molecular Probe ◽

Hookworm Infection ◽

Food Handlers ◽

The Public ◽

Necator Americanus ◽

Link Type ◽

Stool Samples

Background: Hookworms infect the intestines, cause an itchy rash, respiratory and gastrointestinal problems, and eventually iron deficiency (anaemia) due to the ongoing loss of blood. The objectives of this study were to assess the prevalence and molecular characterization of hookworms isolated from food handlers attending the Public Health Laboratories in Khartoum state, Sudan, for annual check-ups, and to assess the efficiency of PCR as molecular probe for hookworm infection. Methods: A total of 350 foods handlers’ participant's stool samples who were not suspected to be infected with hookworms were studied. Conventional methods were applied to make an early diagnosis. Stool samples were collected from public health laboratories (the public health lab in the Medical Commission) of Khartoum State; Omdurman locality, Khartoum North locality and Khartoum locality between October 2016 and April 2017. Specific identification was made by PCR on specimens identified as positive by Baermann’s technique, which were then sequence and genotyped Results: The prevalence of hookworms in the stool samples of food-handlers was 1.43%. One larval specimen recovered by Baermann’s technique was confirmed to be Necator americanus by PCR. PCR also confirmed that Necator americanus was the common species isolated from four further specimens. The results of DNA sequencing for Necator americanus were deposited in NCBI GenBank under the following accession numbers: sample 91, MH035824; sample 92, MH035825; sample 294, MH035826; and sample 319 MH035827. Conclusion: PCR was found to be effective for confirmation of the diagnosis of hookworm infection and can aid the clinician in initiating prompt and appropriate antiparasite therapy.

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