Estudio microbiológico de bacteriemias y fungemias en pacientes en hemodiálisis crónica / [Microbiologic study of bacteremia and fungemia in chronic hemodialysis patients]

Microbiologic study of bacteremia and fungemia in chronic hemodialysis patients. Bloodstream infections are the second cause of death in patients in chronic hemodialysis (CHD), and the knowledge of the epidemiology is useful to establish proper empiric therapies. The aim of this study was to evaluate the frequency and distribution of microorganisms, in bacteremia and fungemia in 530 patients in CHD. Two hundred and forty eight blood culture series from 114 patients with suspected bacteremia were processed; 44

(n=78) were clinically significative and belonged to 58 patients. Sixty eight percent of these isolates were gram-positive cocci (n:53), and 22

gram-negative rods (n:17). Staphylococcus aureus was the most prevalent pathogen showing 23

of methicillin-resistance. Candida spp. was the fourth pathogen most common in frequency.

Susceptibility of Candida species to fluconazole assayed by a disk diffusion method with automated reading versus a microdilution method

In vitro susceptibilities of 290 isolates of Candida spp to fluconazole were evaluated by a new NCCLS M44-P agar disk diffusion method that was read and interpreted automatically by the BIOMIC image-analysis plate reader system. Disk test results were compared to results obtained by a modified NCCLS M27-A broth microdilution method using RPMI-1640 supplemented with 2

. Category agreement between the broth and disk test results for susceptible, susceptible dose-dependent and resistant disk results were 99.6

major discrepancies, and 8.97

minor discrepancies were observed between results of the two test methods. This analysis suggests that results from both methods correlate highly for Candida strains susceptible to fluconazole. The lower agreement between the two methods for resistant and susceptible dose-dependent isolates was due to strains near or on that breakpoint, different media (Mueller-Hinton vs RPMI), agar vs broth, 80

endpoints, and trailing growth near the endpoints.

Estudio comparativo de los genotipos de Candida albicans aislados de pacientes inmunocomprometidos y portadores sanos / [Comparative study of the Candida albicans genotypes isolated from immunocompromised patients and health carriers]

The aim of this study is to compare Candida albicans strain genotype isolates from oral cavity of immunocompromised patients due to different immunologic impairments with apparently normal carriers. Four populations were studied: 1) HIV positive hospitalized patients, 2) HIV negative immunocompromised patients (leukemia, lymphoma, organ transplant recipients), 3) drug addicts prior to AIDS pandemia in Argentina, 4) apparently normal carriers. DNA extracted was digested with the enzyme Eco RI, electrophoresed, transferred to nitrocellulose membrane and hybridized with the 27A probe labelled with 32P. The comparison between the profiles obtained permitted the differentiation of 16 genotypes. The distribution of the strains led to the conclusion that: a) all the isolated strains from AIDS patients were closely related and distributed in only three genotypes (1, 3, 11); b) a major genetic relationship between the isolates from AIDS patients and HIV negative immunocompromised patients was observed; c) strains from carriers showed a minor genetic similarity with those obtained from AIDS patients; d) characteristic profiles belonging to any of the studied groups were not found; e) significant genomic changes have not been observed during the last twenty years.

Características epidemiológicas de 71 casos de criptococosis diagnosticados en diferentes centros asistenciales de la ciudad de Buenos Aires y sus alrededores, durante 1991 / Epidemiological characteristics of 71 cases of cryptococcosis diagnosed in different medical centers of the city of Buenos Aires and its suburbs, in 1991

Se estudiaron algunas características epidemiológicas de 71 casos de criptococosis diagnosticados en 8 centros asistenciales de la ciudad de Buenos Aires y el Gran Buenos Aires, durante 1991. Los hospitales Muñiz y Fernández, comunicaron cerca del 85 por ciento de los casos. El 89 por ciento de los pacientes era de sexo masculino. Las causas predisponentes fueron SIDA (66 casos), transplante renal (2 casos), hepatopatía autoinmune tratada con corticoides, diabetes descompensada y embarazo/puerperio. La mediana de la edad fue de 27 años en la población total (rango 19-62), de 27 años en los casos asociados al SIDA (rango 19-50) y de 50 años en los no asociados a esa enfermedad (rango 24-62). El 56 por ciento de los pacientes se ubicó en el grupo etario de 20-29 años de edad. Una estimación indirecta permite suponer que el porcentaje de pacientes con SIDA que padecieron criptococosis durante 1991 en el área en estudio fue de 25,88 por ciento. El 100 por ciento de 32 casos de Cryptococcus neoformans aisladas de los pacientes fueron identificadas como variedad neoformans. La criptococosis aumenta año a año su incidencia en nuestro medio, paralelamente con su causa predisponente más importante, el SIDA. Su transformación potencial en un problema sanitario, debe alertar a la autoridades competentes