bioRxiv Science⌕ Search

bioRxiv · 10.1101/510107

Automation for the identification of Pseudomonas aeruginosa: Comparison of TDR-300B, VITEK(R)2, and VITEK(R)-MS

Abstract

Quick and precise methods have always been needed in the medical field to correctly identify the agent of infection. Automated systems for diagnosis of infectious pathogen such Pseudomonas aeruginosa from critical patients with infections in the Intensive Care Unit is essential. This study aimed to compare the capability of automated biochemistry-based identification system, TDR-300B and VITEK(R)2, to the one of Matrix-Assisted Laser Desorption/Ionization - Time of Flight (MALDI-TOF), VITEK(R)-MS, in the identification of P. aeruginosa.\n\nSamples were P. aeruginosa isolates collection from Laboratory of Microbiology, Faculty of Medicine and Health Science UNIKA Atma Jaya. These isolates were refreshed; one single colony of oxidase-positive Gram-negative rods was further inoculated in TDR-300B NF-64 cards and VITEK(R)2 GN cassettes. The bacterial identification was also carried out using VITEK(R)-MS as gold-standard. Positivity of TDR-300B and VITEK(R)2 in the identification of P. aeruginosa was 87.09% (27/31) and 90.32% (28/31) in the species level, and 87.09%, 96.77% in the genus level respectively. The congruity of TDR-300B/ VITEK(R)2 in the species and genus level was 83.87% and 87.09%. When compared to VITEK(R)-MS, congruence of VITEK(R)2 was 93.30% (24/26) and TDR-300B was 80.76% (21/26). Sensitivity value for TDR-300B and VITEK(R)2 was high, 95.45% and 100%, positive predictive value and accuracy were lower in TDR-300B than VITEK(R)2; Fisher exact value was >0.05, thus there were no significant differences in the capability of TDR-300B and VITEK(R)2 in the identification of P. aeruginosa.

Source connections

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Moehario, L. H., Boestami, H. P., Edbert, D., Tjoa, E., Robertus, T.. 2019-01-04. Automation for the identification of Pseudomonas aeruginosa: Comparison of TDR-300B, VITEK(R)2, and VITEK(R)-MS. https://doi.org/10.1101/510107

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

A Staphylococcus phage recombination cassette that enables recombineering across distant bacteria

Modifying bacterial genomes with phage recombinases, a process termed recombineering, has enabled precise genome editing, but its reach is limited by host specificity: each new organism generally requires its own recombinase to be identified and optimized. Using known phage recombination genes as synteny anchors, we mined Staphylococcus genomes and recovered a diverse collection of phage recombination cassettes, spanning the RAD52-like annealase superfamily (Sak, Erf) and the RAD51/RecA-like Sak4 family. Functional testing of representatives in S. aureus identified several highly efficient systems that support recombineering. We engineered the most efficient of these into a single-plasmid tool that yields markerless editing in S. aureus in four days. Notably, where other recombineering systems rely on host-specific factors for nuclease evasion and ssDNA loading, this cassette encodes both activities itself: a predicted broad-spectrum nuclease inhibitor and a dedicated single-stranded DNA-binding protein. We therefore tested the cassette across phylogenetically distant hosts, and observed recombination in Streptococcus pyogenes, Enterococcus faecium, Francisella novicida, and Escherichia coli. These results identify a self-sufficient class of phage recombination systems and provide a portable tool for

microbiology↗

Phenotypic and Molecular Characterization of Potentially New Shigella boydii Serotype in Bangladesh

Objective: Shigella is a major cause of bacillary dysentery among children under 5 years of age, especially in low- and middle-income countries. At Dhaka hospital of icddr,b, every year around 3% of Shigella isolates from patients with diarrhea are identified as Shigella-like organisms (SLOs). These isolates do not react with any of the existing and provisional Shigella antisera. The major aims of the present study were to characterize a unique cluster of SLOs using phenotypic and genotypic methods. Methods: A cluster of 6 SLOs was characterized using biochemical tests, serotyping, antimicrobial susceptibility, and virulence assay by using the Sereny test, PCR and compared their pulsed-field gel electrophoresis (PFGE) patterns with known serotypes of Shigella spp. Antisera against the isolate were raised in a rabbit model to determine cross-reactivity with known serotypes. Results: All six SLOs were mannitol fermenting, have invasive properties, positive for ipaH and Shigella enterotoxin 2 gene along with possession of virulence plasmid of ~ 140 MDa. All isolates were resistant to ampicillin, tetracycline, sulfamethoxazole-trimethoprim, but were sensitive to mecillinam, nalidixic acid, and ciprofloxacin. Plasmid and PFGE profiles showed that the genomic patterns of these isolates were identical but were different from all other S. boydii serotypes. Antiserum prepared against one of the isolates agglutinated with all isolates but did not cross-react with other Shigella and E. coli reference strains. Conclusion: This unique cluster of isolates might belong to a new provisional serovar of S. boydii and further analysis is required to incorporate it into the stereotypic scheme of Shigella.

microbiology↗

Long-read shotgun metagenomics identifies distinct urogenital microbial community states associated with functional potential and urinary tract infection during pregnancy

Urinary tract infections (UTIs) are among the most common bacterial infections during pregnancy and are associated with adverse maternal and neonatal outcomes. Although previous studies used enhanced culture, 16S rRNA gene sequencing, and/or short-read shotgun metagenomic sequencing to characterize the urogenital microbiome of adult females, few have assessed the urogenital microbiome during pregnancy and thus this microbiome remains poorly understood. Here, we applied Oxford Nanopore long-read shotgun metagenomic sequencing to characterize urogenital microbial composition, functional potential, metagenome-assembled genomes (MAGs), and the urogenital virome of pregnant females. Taxonomic profiling identified three distinct microbial community states predominated by Lactobacillus crispatus, Gardnerella species, and L. iners. The Gardnerella-predominated community was associated with a higher frequency of UTI during pregnancy. Functional profiles strongly reflected these community states, demonstrating that taxonomic differences were accompanied by distinct functional potential. Genome-resolved analysis recovered 415 MAGs, including 29 high-quality genomes, revealing substantial genomic diversity among urogenital microbes. Viral sequences, predominantly bacteriophages, also were detected in most samples, highlighting an additional component of the pregnancy-associated urogenital microbiome. These findings demonstrate that pregnant females possess distinct urogenital microbial community states and show that they differ not only in taxonomic composition but also in their functional potential.

microbiology↗