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Semi-Quantitative Assay to Measure Urease Activity by Urinary Catheter-Associated Uropathogens

Catheter-associated urinary tract infections (CAUTIs) are one of the most common healthcare-associated infections in the US, accounting for over 1 million cases annually and totaling 450 million USD. CAUTIs have high morbidity and mortality rates and can be caused by a wide range of pathogens, makin...

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Autores principales: Duran Ramirez, Jesus M., Gomez, Jana, Obernuefemann, Chloe L. P., Gualberto, Nathaniel C., Walker, Jennifer N.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2022
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8980526/
https://www.ncbi.nlm.nih.gov/pubmed/35392611
http://dx.doi.org/10.3389/fcimb.2022.859093
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author Duran Ramirez, Jesus M.
Gomez, Jana
Obernuefemann, Chloe L. P.
Gualberto, Nathaniel C.
Walker, Jennifer N.
author_facet Duran Ramirez, Jesus M.
Gomez, Jana
Obernuefemann, Chloe L. P.
Gualberto, Nathaniel C.
Walker, Jennifer N.
author_sort Duran Ramirez, Jesus M.
collection PubMed
description Catheter-associated urinary tract infections (CAUTIs) are one of the most common healthcare-associated infections in the US, accounting for over 1 million cases annually and totaling 450 million USD. CAUTIs have high morbidity and mortality rates and can be caused by a wide range of pathogens, making empiric treatment difficult. Furthermore, when urease-producing uropathogens cause symptomatic CAUTI or asymptomatic catheter colonization, the risk of catheter failure due to blockage increases. The enzyme urease promotes catheter blockage by hydrolyzing urea in urine into ammonia and carbon dioxide, which results in the formation of crystals that coat the catheter surface. If CAUTI is left untreated, the crystals can grow until they block the urinary catheter. Catheter blockage and subsequent failure reduces the quality of life for the chronically catheterized, as it requires frequent catheter exchanges and can promote more severe disease, including dissemination of the infection to the kidneys or bloodstream. Thus, understanding how urease contributes to catheter blockages and/or more severe disease among the broad range of urease-producing microbes may provide insights into better prevention or treatment strategies. However, clinical assays that detect urease production among clinical isolates are qualitative and prioritize the detection of urease from Proteus mirabilis, the most well-studied uropathogenic urease producer. While urease from other known urease producers, such as Morganella morganii, can also be detected with these methods, other uropathogens, including Staphylococcus aureus and Klebsiella pneumonia, are harder to detect. In this study, we developed a high throughput, semiquantitative assay capable of testing multiple uropathogens in a rapid and efficient way. We validated the assay using Jack Bean urease, the urease producing species: Proteus spp., M. morganii, K. pneumonia, and S. aureus strains, and the non-urease producer: Escherichia coli. This modified assay more rapidly detected urease-producing strains compared to the current clinical test, Christensen Urea Agar, and provided semiquantitative values that may be used to further investigate different aspects of urease regulation, production, or activity in these diverse species. Furthermore, this assay can be easily adapted to account for different environmental stimuli affecting urease production, including bacterial concentration, aeration, or addition of anti-urease compounds.
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spelling pubmed-89805262022-04-06 Semi-Quantitative Assay to Measure Urease Activity by Urinary Catheter-Associated Uropathogens Duran Ramirez, Jesus M. Gomez, Jana Obernuefemann, Chloe L. P. Gualberto, Nathaniel C. Walker, Jennifer N. Front Cell Infect Microbiol Cellular and Infection Microbiology Catheter-associated urinary tract infections (CAUTIs) are one of the most common healthcare-associated infections in the US, accounting for over 1 million cases annually and totaling 450 million USD. CAUTIs have high morbidity and mortality rates and can be caused by a wide range of pathogens, making empiric treatment difficult. Furthermore, when urease-producing uropathogens cause symptomatic CAUTI or asymptomatic catheter colonization, the risk of catheter failure due to blockage increases. The enzyme urease promotes catheter blockage by hydrolyzing urea in urine into ammonia and carbon dioxide, which results in the formation of crystals that coat the catheter surface. If CAUTI is left untreated, the crystals can grow until they block the urinary catheter. Catheter blockage and subsequent failure reduces the quality of life for the chronically catheterized, as it requires frequent catheter exchanges and can promote more severe disease, including dissemination of the infection to the kidneys or bloodstream. Thus, understanding how urease contributes to catheter blockages and/or more severe disease among the broad range of urease-producing microbes may provide insights into better prevention or treatment strategies. However, clinical assays that detect urease production among clinical isolates are qualitative and prioritize the detection of urease from Proteus mirabilis, the most well-studied uropathogenic urease producer. While urease from other known urease producers, such as Morganella morganii, can also be detected with these methods, other uropathogens, including Staphylococcus aureus and Klebsiella pneumonia, are harder to detect. In this study, we developed a high throughput, semiquantitative assay capable of testing multiple uropathogens in a rapid and efficient way. We validated the assay using Jack Bean urease, the urease producing species: Proteus spp., M. morganii, K. pneumonia, and S. aureus strains, and the non-urease producer: Escherichia coli. This modified assay more rapidly detected urease-producing strains compared to the current clinical test, Christensen Urea Agar, and provided semiquantitative values that may be used to further investigate different aspects of urease regulation, production, or activity in these diverse species. Furthermore, this assay can be easily adapted to account for different environmental stimuli affecting urease production, including bacterial concentration, aeration, or addition of anti-urease compounds. Frontiers Media S.A. 2022-03-22 /pmc/articles/PMC8980526/ /pubmed/35392611 http://dx.doi.org/10.3389/fcimb.2022.859093 Text en Copyright © 2022 Duran Ramirez, Gomez, Obernuefemann, Gualberto and Walker https://creativecommons.org/licenses/by/4.0/This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
spellingShingle Cellular and Infection Microbiology
Duran Ramirez, Jesus M.
Gomez, Jana
Obernuefemann, Chloe L. P.
Gualberto, Nathaniel C.
Walker, Jennifer N.
Semi-Quantitative Assay to Measure Urease Activity by Urinary Catheter-Associated Uropathogens
title Semi-Quantitative Assay to Measure Urease Activity by Urinary Catheter-Associated Uropathogens
title_full Semi-Quantitative Assay to Measure Urease Activity by Urinary Catheter-Associated Uropathogens
title_fullStr Semi-Quantitative Assay to Measure Urease Activity by Urinary Catheter-Associated Uropathogens
title_full_unstemmed Semi-Quantitative Assay to Measure Urease Activity by Urinary Catheter-Associated Uropathogens
title_short Semi-Quantitative Assay to Measure Urease Activity by Urinary Catheter-Associated Uropathogens
title_sort semi-quantitative assay to measure urease activity by urinary catheter-associated uropathogens
topic Cellular and Infection Microbiology
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8980526/
https://www.ncbi.nlm.nih.gov/pubmed/35392611
http://dx.doi.org/10.3389/fcimb.2022.859093
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