Genomic heterogeneity underlies multidrug resistance in Pseudomonas aeruginosa: A population-level analysis beyond susceptibility testing

• Autores: Rojas, Laura J.; Yasmin, Mohamad; Benjamino, Jacquelynn; Marshall, Steven M.; DeRonde, Kailynn J.; Krishnan, Nikhil P.; Perez, Federico; Colin, Andrew A.; Cardenas, Monica; Martinez, Octavio; Pérez Cardona, Armando; Rhoads, Daniel D.; Jacobs, Michael R.; LiPuma, John J.; Konstan, Michael W.; Vila, Alejandro Jose; Smania, Andrea; Mack, Andrew R.; Scott, Jacob G.; Adams, Mark D.; Abbo, Lilian M.; Bonomo, Robert A.
• Año de publicación: 2022
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: antibiotic; phenotypes; resistance
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

Background Pseudomonas aeruginosa is a persistent and difficult-to-treat pathogen in many patients, especially those with Cystic Fibrosis (CF). Herein, we describe a longitudinal analysis of a series of multidrug resistant (MDR) P. aeruginosa isolates recovered in a 17-month period, from a young female CF patient who underwent double lung transplantation. Our goal was to understand the genetic basis of the observed resistance phenotypes, establish the genomic population diversity, and define the nature of sequence evolution over time. Methods Twenty-two sequential P. aeruginosa isolates were obtained within a 17-month period, before and after a double-lung transplant. At the end of the study period, antimicrobial susceptibility testing, whole genome sequencing (WGS), phylogenetic analyses and RNAseq were performed in order to understand the genetic basis of the observed resistance phenotypes, establish the genomic population diversity, and define the nature of sequence changes over time. Results The majority of isolates were resistant to almost all tested antibiotics. A phylogenetic reconstruction revealed 3 major clades representing a genotypically and phenotypically heterogeneous population. The pattern of mutation accumulation and variation of gene expression suggested that a group of closely related strains was present in the patient prior to transplantation and continued to change throughout the course of treatment. A trend toward accumulation of mutations over time was observed. Different mutations in the DNA mismatch repair gene mutL consistent with a hypermutator phenotype were observed in two clades. RNAseq performed on 12 representative isolates revealed substantial differences in the expression of genes associated with antibiotic resistance and virulence traits. Conclusions The overwhelming current practice in the clinical laboratories setting relies on obtaining a pure culture and reporting the antibiogram from a few isolated colonies to inform therapy decisions. Our analyses revealed significant underlying genomic heterogeneity and unpredictable evolutionary patterns that were independent of prior antibiotic treatment, highlighting the need for comprehensive sampling and population-level analysis when gathering microbiological data in the context of CF P. aeruginosa chronic infection. Our findings challenge the applicability of antimicrobial stewardship programs based on single-isolate resistance profiles for the selection of antibiotic regimens in chronic infections such as CF.
Fil: Rojas, Laura J.. Case Western Reserve University School of Medicine; Estados Unidos
Fil: Yasmin, Mohamad. No especifíca;
Fil: Benjamino, Jacquelynn. No especifíca;
Fil: Marshall, Steven M.. No especifíca;
Fil: DeRonde, Kailynn J.. No especifíca;
Fil: Krishnan, Nikhil P.. Case Western Reserve University School of Medicine; Estados Unidos
Fil: Perez, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Química Biológica de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Centro de Investigaciones en Química Biológica de Córdoba; Argentina
Fil: Colin, Andrew A.. University of Miami; Estados Unidos
Fil: Cardenas, Monica. University of Miami; Estados Unidos
Fil: Martinez, Octavio. University of Miami; Estados Unidos
Fil: Pérez Cardona, Armando. No especifíca;
Fil: Rhoads, Daniel D.. No especifíca;
Fil: Jacobs, Michael R.. No especifíca;
Fil: LiPuma, John J.. University of Michigan; Estados Unidos
Fil: Konstan, Michael W.. No especifíca;
Fil: Vila, Alejandro Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; Argentina
Fil: Smania, Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Química Biológica de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Centro de Investigaciones en Química Biológica de Córdoba; Argentina
Fil: Mack, Andrew R.. Case Western Reserve University School of Medicine; Estados Unidos
Fil: Scott, Jacob G.. Case Western Reserve University School of Medicine; Estados Unidos
Fil: Adams, Mark D.. No especifíca;
Fil: Abbo, Lilian M.. University of Miami; Estados Unidos
Fil: Bonomo, Robert A.. Case Western Reserve University School of Medicine; Estados Unidos