Marta Tokumoto

Complex Class 1 Integrons with Diverse Variable Regions, Including aac(6′)-Ib-cr, and a Novel Allele, qnrB10, Associated with ISCR1 in Clinical Enterobacterial Isolates from Argentina

ABSTRACT Transferable quinolone resistance has not previously been reported in Argentina. Here we describe three complex class 1 integrons harboring the novel allele qnrB10 in a unique region downstream of orf513, one of them also containing aac(6′)-Ib-cr within the variable region of integrons. The three arrays differed from blaCTX-M-2-bearing integrons, which are broadly distributed in Argentina.

Class 2 Integron with a Novel Cassette Array in a Burkholderia cenocepacia Isolate

Burkholderia cepacia complex (BCC) organisms are gram-negative opportunistic emerging pathogens associated with a poor prognosis for patients with cystic fibrosis (CF) ([10][1]). Carbapenems and ceftazidime are administered to patients suffering from BCC infections, and trimethoprim-sulfamethoxazole

Emergence of a Streptococcus pneumoniae clinical isolate highly resistant to telithromycin and fluoroquinolones

ABSTRACT Streptococcus pneumoniae is a major pathogen causing community-acquired pneumonia and acute bronchitis. Macrolides, fluoroquinolones (FQs), and, recently, telithromycin (TEL) constitute primary therapeutic options, and rare cases of resistance have been reported. In this report, we describe the emergence of an S. pneumoniae clinical isolate with high-level TEL resistance (MIC, 256 μg/ml) and simultaneous resistance to FQs. Ongoing studies are oriented to elucidate the precise mechanism of resistance to TEL.

Vigilancia de la resistencia a los antibacterianos en Argentina. Programa WHONET, 1995-1996

La Organizacion Mundial de la Salud ha puesto en marcha un programa para la vigilancia de la resistencia a los antibacterianos, denominado WHONET, que se desarrollo en Argentina mediante una red de 23 laboratorios de instituciones hospitalarias publicas y privadas someti-dos a programas nacionales e internacionales de control de calidad. Entre enero de 1995 y di-ciembre de 1996 se determino por el metodo de difusion en agar la sensibilidad a los antibacte-rianos de 16 073 aislados clinicos consecutivos, siguiendo las recomendaciones del Comite Nacional de Estandares para Laboratorios Clinicos (National Committee for Clinical Labo-ratory Standards:NCCLS) de los Estados Unidos de America. Mas de la mitad de los aisla-dos urinarios de Escherichia colifueron resistentes a la ampicilina, y mas de 30% a la trime-toprima-sulfametoxazol. Cuando se comparo la sensibilidad de los aislados urinarios de pacientes ambulatorios y hospitalizados, se observo una marcada diferencia en los perfiles de actividad (porcentaje de microorganismos resistentes aislados en pacientes hospitalizados frente a pacientes ambulatorios) de la gentamicina (8% frente a 2%), la norfloxacina (6% frente a 2%) y las cefalosporinas de tercera generacion (18% frente a 10%). Los aislados de Klebsiella pneumoniaerecuperados de hemocultivos presentaron resistencia a las cefalospo-rinas de tercera generacion y a la gentamicina en 71 y 60% de los casos, respectivamente. La proporcion de Staphylococcus aureusresistentes a la oxacilina fue de 39%. Cerca de la mitad de los aislados de Enterococcusspp. presentaron resistencia de alto nivel a los aminoglucosi-dos, pero no se detecto resistencia a los glicopeptidos. En nuestro medio, la ampicilina y la tri-metoprima-sulfametoxazol no fueron apropiadas para el tratamiento de las diarreas; Shigella flexneripresento mayor porcentaje de aislados resistentes a ambos farmacos (87 y 74%, res-pectivamente) que Shigella sonnei(47 y 71%, respectivamente). Se detecto resistencia a las cefalosporinas de tercera generacion en 40% de los aislados de Salmonella spp. recuperados en hospitales pediatricos. En casos de meningitis bacteriana, las tasas de resistencia de Strep-tococcus pneumoniaea la penicilina (18%) y de Haemophilus influenzaea la ampicilina (19%) se situaron en el rango intermedio de las descritas en paises americanos y europeos.

Phenotypic and genotypic characterisation of Candida dubliniensis isolate in a patient with disseminated candidiasis

Analia Fernandez, Virginia M. Jewtuchowicz, Maria Celina Malzone, Gabriela Lopez-Daneri, Gladys Saa, Cristina A. Iovannitti, Marta Tokumoto and Maria T. Mujica Laboratorio Central Servicio de Microbiologı́a, Hospital Universitario Fundación Favaloro, Buenos Aires, Argentina, Unidad de Cuidados Intensivos Pediátricos, Hospital Universitario Fundación Favaloro, Buenos Aires, Argentina and Departamento de Microbiologı́a, Parasitologı́a e Inmunologı́a de la Facultad de Medicina de la Universidad de Buenos Aires, Buenos Aires, Argentina

Phenotypic and molecular identification of Coccidioides posadasii in a patient evaluated for bilateral lung transplantation

BACKGROUND Coccidioidomycosis is an endemic fungal infection caused by Coccidioides immitis and Coccidioides posadasii. It can be particularly severe in transplant recipients that have a current or a previous coccidioidal infection. Fatal case of coccidioidomycosis has been described in this group of patients. AIMS We report a severe case of pneumonia caused by C. posadassi in a 29 year-old white woman that had been admitted to hospital as part of the evaluation for bilateral lung transplantation. The patient was a native and resident of Catamarca, Argentina. Molecular methodologies contributed to the species identification. METHODS Clinical, laboratory records and microbiological tests were carried out to diagnose the infection and to identify C. posadasii. RESULTS A fungus was isolated from BAL culture. Phenotypic characterization, specific PCR and experimental animal inoculation demonstrated the presence of C. posadasii. The patient responded well to amphotericin B deoxycholate. Lung transplantation was postponed. CONCLUSIONS Specific PCR can be an important alternative for the correct identification of C. immitis or C. posadasii in laboratories with implemented molecular biology tools. This case emphasizes the need for a systematic assessment in organ transplant units of patients inhabiting endemic areas of coccidioidomycosis.