Detección fenotípica de metalobetalactamasas en aislados clínicos de Pseudomonas aeruginosa

Abstract: Pseudomonas aeruginosa is considered one of the most important hospital germs; its isolation is common in hospitalized patients. In addition, this microorganism has a marked multiresistance, which increases mortality. Treatment of these patients is often difficult, since in addition to its...

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Bibliographic Details
Main Authors: Perozo-Mena Armindo José, Castellano-González Maribel Josefina, Ling-Toledo Eliana, Arraiz Nailet
Format: Article in Journal/Newspaper
Language:English
Spanish
Published: Universidad del Zulia,Facultad de Medicina,Departamento de Enfermedades Infecciosas y Tropicales 2012
Subjects:
MBL
Online Access:https://doaj.org/article/2fe7b055b4484cf09e72765bf991c0c3
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Summary:Abstract: Pseudomonas aeruginosa is considered one of the most important hospital germs; its isolation is common in hospitalized patients. In addition, this microorganism has a marked multiresistance, which increases mortality. Treatment of these patients is often difficult, since in addition to its natural resistance, Pseudomonas can obtain resistance mechanisms to virtually all ant microbial drugs available for its treatment; due to this, its appearance is increasingly frequent and necessitates the use of antibiotics such as carbapenems, which facilitates the acquisition of resistance mechanisms to these drugs. This study attempts to determine the production of metallobeta-lactamase (MBL) in clinical isolates of Pseudomonas aeruginosa, utilizing two phenotypic methods: the double disc method (MDD) and the modified Hodge test (MHT). 726 clinical isolates of P. aeruginosa were analyzed; 20.11% (146) of these were resistant to imipenem (IPM) and meropenem (MEM); 139 were positive for the MDD, while 144 were positive for the MHT. These two methods permitted confirming the presence of an MBL-type carbapenemase in 98.63% of P. aeruginosa isolates; five isolates were negative for the MDD but positive for the MHT, indicating the presence of non-MBL-type carbapenemase in these isolates. Also, 2 isolates were obtained that, despite being resistant to IPM and MEM, were negative according to the two phenotypic methods used; this would indicate the presence of a non-enzymatic resistance mechanism conferring resistance to carbapenems. The use of phenotypic methods for detecting MBL in P. aeruginosa isolates is quite an acceptable option for use in routine laboratories where specialized molecular biology tests are not available. Resumen: Pseudomonas aeruginosa, es considerado uno de los más importantes gérmenes hospitalarios, siendo común su aislamiento en pacientes hospitalizados, adicionalmente, este microorganismo presenta una marcada multiresistencia, lo que incrementa la mortalidad. El tratamiento de estos pacientes ...