Prevalence of antibiotic resistance and virulent factors in nosocomial clinical isolates of Pseudomonas aeruginosa from Panamá

ABSTRACT Background: Pseudomonas aeruginosa is an important causative agent of nosocomial infections. As pathogen, P. aeruginosa is of increasing clinical importance due to its ability to develop high-level multidrug resistance (MDR). Methods: The aim of the present study was to better understand the intrinsic virulence of circulating strains of Pseudomonas aeruginosa, by surveying and characterizing the antibiotic resistance profiles and prevalence of virulence factors in 51 clinical isolates of P. aeruginosa obtained from children admitted to Hospital del Niño-Panamá during the period of October 2016 until March 2017. Antimicrobial susceptibilities were assessed by determining the minimum inhibitory concentration for 12 antibiotics against P. aeruginosa clinical isolates using the VITEK system (https://www.biomerieux.com). Additionally, all isolates were examined by Polymerase Chain Reaction (PCR) for the presence of components of the MexAB-OprM efflux pump system (mexABR) and pyoverdine receptor genes and betalactamases resistance genes (ESBL) using gene-specific primers. Results: A total of 51 pyoverdine producing clinical isolates were analyzed, all of which expressed resistance genes such as genes of the MexAB-OprM efflux pump system (mexABR) and pyoverdine receptor genes (fpvA). Out of 51 MDR isolates, 22 were ESBL producers. The most common ESBL gene was blaTEM expressed by 43% of the isolates. The isolates tested in this study showed increased resistance to antibiotics in the following categories: (i) penicillins (ampicillin (69%), piperacillin (22%); (ii) pyrimethamines (trimethoprim, 65%); (iii) nitrofurans (nitrofurantoin, 63%), and (iv) third-generation cephalosporin cefotaxime (53%). These results underscore a high prevalence of MDR amongst clinical isolates from Panama. Conclusions: The present study indicates that prevalence of BlaTEM-carrying strains is increasing with subsequent multidrug resistance in Panamá and as well reported worldwide. The virulent factors identified in this study provide valuable information regarding the prevalence of resistance genes and their potential impact on treatments that exploit the unique physiology of the pathogen. To prevent further spread of MDR, the proportions of resistant strains of Pseudomonas aeruginosa should be constantly evaluated on healthcare institutions of Panamá. More importantly, this information can be used to better understand the evolution and dissemination of strains hoping to prevent the development of resistance in Pseudomonas aeruginosa. Future studies quantifying the expression of these virulent genes will emphasize on the acquisition of multidrug resistance.

Síndrome de Evans Fisher asociado con esclerodermia / Fisher Evans syndrome associated with scleroderma

El síndrome de Evans Fisher, descrito por primera vez en 1951, es un desorden autoinmune caracterizado por la presencia simultánea o secuencial de anemia hemolítica, trombocitopenia inmune y, en ocasiones, neutropenia inmune; con una prueba de antiglobulina directa positiva. Puede ser de causa primaria o secundaria a otras condiciones, como el lupus eritematoso sistémico, los síndromes linfoproliferativos o inmunodeficiencias primarias. Es muy rara su asociación con la esclerodermia. Con el término esclerodermia, que en sentido literal significa piel dura, se designa un grupo de enfermedades y síndromes que tienen como característica común la induración y el engrosamiento cutáneos. Se caracteriza por la presencia de un depósito excesivo de los componentes del tejido conjuntivo, expresado en forma de fibrosis hística, y por alteraciones estructurales del lecho vascular. Con un cuadro clínico muy amplio, afecta fundamentalmente la piel y ciertos órganos internos, como tubo digestivo, pulmón, corazón y riñón. Se presenta una paciente femenina de 75 años de edad, piel negra, con antecedentes de hipertensión arterial, diabetes mellitus tipo 2, cardiopatía isquémica y esclerodermia, esta última diagnosticada seis meses antes de su ingreso. Acudió por decaimiento marcado, palidez cutáneo-mucosa intensa y petequias generalizadas. En los estudios realizados se detectó anemia y trombocitopenia severas, reticulocitosis, prueba de antiglobulina directa positiva e hipercelularidad medular con hiperplasia severa de los sistemas megacariopoyético y eritropoyético. Se diagnosticó un síndrome de Evans Fisher y se trató con esteroides e inmunomoduladores; se logró la mejoría clínica y la remisión hematológica

The Evans syndrome, first described in 1951, is an autoimmune disorder characterized by the simultaneous or sequential development of hemolytic anemia and immune thrombocytopenia or immune neutropenia. It may be of primary origin or secondary to other diseases or conditions such as systemic lupus erythematosus, lymphoproliferative disorders or primary immunodeficiencies. Its association with scleroderma is considered very rare. The word scleroderma, which literally means hard skin, designates a group of diseases and syndromes of common feature in induration and thickening the skin. It is characterized by the presence of excessive deposition of connective tissue components, expressed as histic fibrosis, and structural alterations of the vascular bed. With a broad clinical view, it primarily affects the skin and certain internal organs such as gastrointestinal tract, lung, heart and kidney. We present a 75 year-old female, black skin, with a history of hypertension, type 2 diabetes, ischemic heart disease and scleroderma, the latter diagnosed six months before admission. The patient referred marked weakness, pale skin and generalized petechiae. The complete blood count detected severe anemia, thrombocytopenia and reticulocytosis. Other studies showed positive direct Coombs test and severe hypercellularity. Evans Fisher syndrome was diagnosed and treated with steroids and immunomodulators; clinical improvement and hematologic remission was achieved