Suceptibilidad antifúngica de levaduras mediante etest©: comparación de 3 medios / Antifungal susceptibility testing by etest©: comparison of 3 media

Background: The increasing frequency of systemic fungal infections and the emergence of secondary resistance to antifungals in the lasts years, has stimulated the use of methods for antifungal susceptibility testing. Etest(r) is an easily performed quantitative method that has a good agreement with the broth microdilution reference method (NCCLS), if appropriate media are used. Aim: To compare the susceptibility to Amphotericin B (AmB) and Fluconazole (Flu) of 22 opportunistic yeast isolates (C albicans (7), C tropicalis (9), C parapsilosis (3) and Cryptococcus neoformans (3) by Etest ©., using three different media and to choose the best medium for each tested drug. The studied media were RPMI 1640, Casitone (Cas) and Sabouraud. Results: The interpretation of minimal inhibitory concentration (MIC) endpoints on Sabouraud was difficult for AmB. The American Type Culture Collection (ATCC) strains MICs were out of the acceptable range in this medium. RPMI and Cas were suitable media to test AmB and Flu, but best endpoints were obtained for AmB in RPMI and Flu in Cas. Conclusions: The use of appropriate media for each antifungal drug optimizes the MIC readings by Etest(r). AmB should be tested in RMPI and Flu in Cas. Sabouraud must not be used

Puesta al día en enterococos año 2001: identificación de especies y estudio de susceptibilidad antimicrobiana / Update on microbiological topics of enterococci year 2001: identification of species and antimicrobial susceptibility technics

In recent years, enterococci have emerged as important pathogens. These organisms are now the third most commonly encountered nosocomial bloodstream infection pathogens in many part of the world. Due to increasing frequency with which multi-drug resistant enterococci are isolated from clinical specimens, there is a need for rapid reporting of results of identification tests and tests for susceptibility testing to antimicrobial agents. In 1999, we published an update of regarding the identification of the different species of enterococci as well as the recommendations for accurately detecting resistance among these isolates. In the current report, we will discuss additional tests for identification of enterococcal species as well as, the current recommendations for susceptibility testing

Neumonía por pneumocystis carinii: factores predisponentes, manifestaciones clínicas y respuesta a tratamiento / Pneumocystis carinii pneumonia: risk factors, clinical manifestations and treatment outcome

Presentamos una serie de 43 pacientes con neumonía por P. carinii confirmada ya sea por anatomía patológica y/o RPC, destacando como patología de base más frecuente el SIDA, pero también se pesquisaron casos en pacientes con otras inmunodeficiencias, leucemia linfoblástica aguda, tratamiento inmunosupresor y linfopenia idiopática. En los pacientes infectados por VIH la evolución del cuadro fue larvada mientras que en los pacinetes leucémicos la presentación clínica del cuadro fue más agresiva. Destacó la tríada sintomática de fiebre, tos y disnea como los hallazgos clínicos más frecuentes, junto a una elevación constante de LDH y un recuento de CD4 inferior a 200 células/mm3. La mayoría de los pacientes presentó un patrón radiológico de tipo retículo nodular, aunque se evidenciaron también condensaciones y radiografías de tórax normales. La mayoría de los pacientes presentó una evolución clínica favorable con pocas reacciones adversas severas a cotrimoxazol, pero sí más frecuentes a pentamidina intravenosa. En el subgrupo de pacientes admitidos en UCI se observó una elevada letalidad

Puesta al día en aspectos microbiológicos de enterococos / Update on microbiological topics of enterococci

Clinical microbiology laboratories are faced with the challenge of accurate detection of emerging antibiotic resistance among several important gram positive bacterial pahtogens. For enterococci, vancomycin and ampicillin resistance was significantly more prevalent among E. faecium than among E. faecalis. This finding undescores the importance of identifying enterococcal isolates to species for the sake of more precise surveillance. Enterococci are identified to the genus level with tests like pyrrolidine amilaridase, bile esculin and salt tolerance, but in some instances, species identification is desirable. Initial characterization of the species, as well as the antimicrobial susceptibility testing in enterococci, will be discussed in this report