RESUMEN
Bacterial bloodstream infections (BSI) are a common threat among patients with haematological malignancies (HM) and hematopoietic stem cell transplant recipients (HSCT). The purpose of this research was to describe clinical and microbiological aspects of BSI caused by carbapenem-resistant Klebsiella pneumoniae (CRKp) and assess risk factors associated with 30-day mortality in a 10-year cohort of haematological patients. A total of 65 CRKp-BSI episodes occurring in HM patients and HSCT recipients and CRKp-BSI between January 2010 and December 2019 were retrospectively studied. Acute leukemias were the most frequently observed underlying disease (87.7%) and 18 patients (27.7%) received HSCT. Mucosal barrier injury in the gastrointestinal tract was the primary cause of bacteremia (86.1%). Also, 14 individuals (21.6%) had an Invasive Fungal Disease (IFD) throughout the episode. Regarding treatment, in 31 patients (47.7%) empirical therapy was deemed appropriate, whereas 33 (50.8%) patients received a combination therapy. Microbiological data revealed that the majority of isolates (53-58%) had the Polymyxin B co-resistance phenotype, while amikacin resistance was less common (16 samples, or 24.7%). The mortality rates at 14 and 30 days were 32.3% and 36.9%, respectively. In a multivariate Cox regression analysis, prompt appropriate antibiotic administration within three days was associated with a better outcome (Adjusted Hazard Ratio [aHR]: 0.33; 95% Confidence Interval [CI]: 0.14-0.76; p = 0.01), whereas hypotension at presentation (aHR: 3.88; 95% CI: 1.40-10.74; p = 0.01) and concurrent IFD (aHR: 2.97; 95% CI: 1.20-7.37; p = 0.02) were independently associated with death within 30 days. Additionally, a favorable correlation between combination therapy and overall survival was found (aHR: 0.18; 95%CI: 0.06-0.56; p = 0.002). In conclusion, 30-day mortality CRKp-BSI was elevated and most of the isolates were polymyxin B resistant. Early appropriate antimicrobial treatment and the use of combination therapy were linked to a better outcome.
Asunto(s)
Bacteriemia , Enterobacteriaceae Resistentes a los Carbapenémicos , Neoplasias Hematológicas , Trasplante de Células Madre Hematopoyéticas , Infecciones por Klebsiella , Humanos , Klebsiella pneumoniae , Estudios Retrospectivos , Polimixina B/uso terapéutico , Brasil/epidemiología , Infecciones por Klebsiella/microbiología , Antibacterianos/uso terapéutico , Bacteriemia/microbiología , Neoplasias Hematológicas/terapia , Neoplasias Hematológicas/tratamiento farmacológico , Carbapenémicos/uso terapéutico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Factores de RiesgoRESUMEN
This study aimed to characterize multidrug-resistant Proteus mirabilis clones carrying a novel class 1 integron-borne blaIMP-1 In1359 was inserted into a large conjugative plasmid that also carried blaCTX-M-2 The production of carbapenemases in Enterobacteriaceae that are intrinsically resistant to polymyxins and tigecycline is very worrisome, representing a serious challenge to clinicians and infection control teams.
Asunto(s)
Regulación Bacteriana de la Expresión Génica , Integrones , Plásmidos/química , Proteus mirabilis/genética , beta-Lactamasas/genética , Antibacterianos/farmacología , Brasil/epidemiología , Carbapenémicos/farmacología , Células Clonales , Farmacorresistencia Bacteriana Múltiple/genética , Humanos , Pruebas de Sensibilidad Microbiana , Plásmidos/metabolismo , Polimixinas/farmacología , Infecciones por Proteus/tratamiento farmacológico , Infecciones por Proteus/epidemiología , Infecciones por Proteus/microbiología , Infecciones por Proteus/transmisión , Proteus mirabilis/efectos de los fármacos , Proteus mirabilis/enzimología , Proteus mirabilis/aislamiento & purificación , Centros de Atención Terciaria , Tigeciclina/farmacología , beta-Lactamasas/metabolismoRESUMEN
The reevaluation of the genus Trichosporon has led to the replacement of the old taxon Trichosporon beigelii by six new species. Sequencing of the ribosomal DNA (rDNA) intergenic spacer 1 (IGS1) is currently mandatory for accurate Trichosporon identification, but it is not usually performed in routine laboratories. Here we describe Trichosporon species distribution and prevalence of Trichosporon asahii genotypes based on rDNA IGS1 sequencing as well as antifungal susceptibility profiles of 22 isolates recovered from blood cultures. The clinical isolates were identified as follows: 15 T. asahii isolates, five Trichosporon asteroides isolates, one Trichosporon coremiiforme isolate, and one Trichosporon dermatis isolate. We found a great diversity of different species causing trichosporonemia, including a high frequency of isolation of T. asteroides from blood cultures that is lower than that of T. asahii only. Regarding T. asahii genotyping, we found that the majority of our isolates belonged to genotype 1 (86.7%). We report the first T. asahii isolate belonging to genotype 4 in South America. Almost 50% of all T. asahii isolates exhibited amphotericin B MICs of >or=2 microg/ml. Caspofungin MICs obtained for all the Trichosporon sp. isolates tested were consistently high (MICs >or= 2 microg/ml). Most isolates (87%) had high MICs for 5-flucytosine, but all of them were susceptible to triazoles, markedly to voriconazole (all MICs Asunto(s)
Antifúngicos/farmacología
, ADN de Hongos/genética
, ADN Espaciador Ribosómico/genética
, Fungemia/epidemiología
, Micosis/epidemiología
, Trichosporon/clasificación
, Trichosporon/efectos de los fármacos
, Adolescente
, Adulto
, Anciano
, Niño
, Preescolar
, ADN de Hongos/química
, ADN Espaciador Ribosómico/química
, Femenino
, Genotipo
, Humanos
, Lactante
, Recién Nacido
, Masculino
, Pruebas de Sensibilidad Microbiana
, Persona de Mediana Edad
, Datos de Secuencia Molecular
, Filogenia
, Prevalencia
, Análisis de Secuencia de ADN
, América del Sur/epidemiología
, Trichosporon/genética
, Trichosporon/aislamiento & purificación
RESUMEN
Trichosporon spp. are widely distributed in nature and can occasionally belong to the human microbiota. For many years, the unique species of the genus, Trichosporon beigelli, was only known as an environmental and saprophytic fungus occasionally found as the etiological agent of white piedra. However, case reports of invasive trichosporonosis have been frequently published and the genus is currently considered the second most common agent of yeasts disseminated infections. Based on molecular analysis, the taxon T. beigelli was replaced by several species and the taxonomy of the genus was progressively modified. Despite the reported increase of Trichosporon infections refractory to conventional antifungal drugs, there are only a few studies investigating in vitro susceptibility of Trichosporon spp. to new compounds. Difficulties on different species identification as well as the lack of standardized sensitivity tests in vitro, contribute to the limited information available on epidemiology, diagnosis and therapeutics of trichosporonosis.