RESUMEN
BACKGROUND: Specific bacterial infections or alterations of the gut microbiota likely trigger immuno-pathological phenomena associated with Crohn's disease and ulcerative colitis. Mycobacterium avium subspecies paratuberculosis is a candidate etiological agent of Crohn's disease. Definitive causal connection between Mycobacterium avium subspecies paratuberculosis infection and Crohn's disease has not been demonstrated. AIMS: To determine the circulation of Mycobacterium avium subspecies paratuberculosis in Crohn's disease patients and water supplies in an Italian region where this bacterium is endemic in cattle farms. METHODS: Mycobacterium avium subspecies paratuberculosis screening was performed on biopsies from human patients, and from water samples, using two different PCR procedures. RESULTS: In hospitals where multiple specimens were obtained from different sites in the intestine, the prevalence of Mycobacterium avium subspecies paratuberculosis infection was 82.1% and 40% respectively in Crohn's disease and ulcerative colitis patients; in another hospital, where single specimens were obtained from patients, the bacterium was not detected. Control subjects also harboured Mycobacterium avium subspecies paratuberculosis, but at a lower prevalence. Tap water samples collected in the study area contained Mycobacterium avium subspecies paratuberculosis DNA. DISCUSSION: The results of screenings for Mycobacterium avium subspecies paratuberculosis in humans are deeply influenced by both the number and location of the collected biopsies. There is a wide circulation of the organism in the study area, considering the prevalence in humans and its presence in drinking water.
Asunto(s)
Enfermedad de Crohn/microbiología , ADN Bacteriano/aislamiento & purificación , Agua Potable/microbiología , Mycobacterium avium subsp. paratuberculosis/aislamiento & purificación , Paratuberculosis/epidemiología , Distribución de Chi-Cuadrado , Colitis Ulcerosa/microbiología , Humanos , Intestinos/microbiología , Italia/epidemiología , Paratuberculosis/complicaciones , PrevalenciaRESUMEN
Efflux transporters have a considerable role in the multidrug resistance (MDR) of Pseudomonas aeruginosa, an important nosocomial pathogen. In this study, 45 P. aeruginosa clinical strains, with an MDR phenotype, have been isolated in a hospital of Northern Italy and characterized to identify the mechanisms responsible for their fluoroquinolone (FQ) resistance. These isolates were analyzed for clonal similarity, mutations in genes encoding the FQ targets, overexpression of specific Resistance Nodulation-cell Division efflux pumps, and search for mutations in their regulatory genes. The achieved results suggested that the mutations in genes encoding ciprofloxacin targets represented the main mechanism of FQ resistance of these strains; 97.8% of these isolates showed mutations in gyrA, 28.9% in gyrB, 88.9% in parC, and 6.7% in parE. Another mechanism of resistance was overexpression of the efflux pumps in some representative strains. In particular, overexpression of MexXY-OprM drug transporter was found in five isolates, whereas overexpression of MexCD-OprJ was detected in two isolates; surprisingly, in one of these last two isolates, also overexpression of MexAB-OprM pump was identified.
Asunto(s)
Antibacterianos/farmacología , Proteínas Bacterianas/genética , Farmacorresistencia Bacteriana Múltiple/genética , Fluoroquinolonas/farmacología , Proteínas de Transporte de Membrana/genética , Pseudomonas aeruginosa/genética , Girasa de ADN/genética , Regulación Bacteriana de la Expresión Génica , Genes Reguladores , Humanos , Pruebas de Sensibilidad Microbiana , Mutación , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/aislamiento & purificación , Técnica del ADN Polimorfo Amplificado AleatorioRESUMEN
Cryptococcoma is a rare entity, characterized by solid, space-occupying masses, usually found in the brain. It has been reported in the setting of "paradoxical" immune reconstitution inflammatory syndrome. A case of retroperitoneal cryptococcoma in a HIV-infected woman with a clinical history of disseminated cryptococcosis on antifungal maintenance therapy is described.