Objective: To assess a LED-fluorescence microscopy (LED-FM) capacitation program for the training of laboratory technicians without previous experience in FM.
Methods: We evaluated a teaching program that consists of a three-day course followed by an "in situ" two-month phase in which technicians acquired skills without the help of a FM expert; in order to gain confidence to recognize auramine-stained bacillus, during this phase, technicians examined duplicate slides stained by Ziehl Neelsen (ZN) and FM in a unblinded way. Technicians with acceptable performance, continued with a blinded-training period.
Introduction: Light-emitting diode fluorescence microscopy (LED-FM) has been endorsed by the World Health Organization (WHO) for tuberculosis diagnosis, but its accuracy in HIV-infected patients remains controversial, and only some few studies have explored procedural factors that may affect its performance.
Objective: To evaluate the performance of LED-FM for tuberculosis diagnosis in patients with and without HIV infection using a newer, less expensive LED lamp.
Materials And Methods: We compared the performance of LED-FM and Ziehl-Neelsen (ZN) microscopy on respiratory specimen smears from tuberculosis (TB) suspects and patients on treatment examined by different technicians blinded for HIV-status and for the result of the comparative test.
Blinded rechecking is a method proposed for external quality assurance (EQA) of auramine-stained acid-fast bacilli (AFB) smears using fluorescence microscopy (FM), however, this procedure is not well developed and slides fading over time could compromise its implementation. Since bleaching of fluorescent molecules involves temperature-dependent chemical reactions, it is likely that low temperatures could slow down this process. We stored auramine-stained slides under different environmental conditions, including -20°C, and examined them over time.
View Article and Find Full Text PDFThe in vitro activity of piperacillin-tazobactam and several antibacterial drugs commonly used in Argentinean hospitals for the treatment of severe infections was determined against selected but consecutively isolated strains from clinical specimens recovered from hospitalized patients at 17 different hospitals from 9 Argentinean cities from different geographic areas during the period November 2001-March 2002. Out of 418 Enterobacteriaceae included in the Study 84% were susceptible to piperacillin-tazobactam. ESBLs putative producers were isolated at an extremely high rate since among those isolates obtained from patients with hospital acquired infections 56% of Klebsiella pneumoniae, 32% of Proteus mirabilis and 25% Escherichia coli were phenotypically considered as ESBLs producers Notably P.
View Article and Find Full Text PDFRev Fac Cien Med Univ Nac Cordoba
December 2003
The interest for the research on enviromental mycobacteria has risen over the last decades, in part, due to a significant incidence rate rise. Reports from all over the world address the soil as the major source for human contamination. In Argentina two documents report the prevalence of atypical mycobacteriosis at Córdoba (1997), and the isolation of enviromental mycobacteria from soils of the Province of La Pampa (1999) respectively.
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