Epidemiología de las fungemias en un hospital pediátrico de alta complejidad / Epidemiology of fungaemia in a paediatric hospital of high complexity

Antecedentes. Se realizó un estudio retrospectivo desde septiembre de 2001 a septiembre de 2003 de las fungemias por levaduras en el Hospital Nacional de Pediatría Prof. Dr. J. Garrahan, de Buenos Aires. Objetivos. Conocer la distribución de las especies de levaduras de interés médico y evaluar el perfil de sensibilidad in vitro a los antifúngicos. Métodos. Se determinó la concentración mínima inhibitoria (CMI) según el documento M27-A2 del CLSI, y además, las curvas de letalidad frente a la anfotericina B. Resultados-Conclusiones. Se aislaron Candida parapsilosis (32,6% de los aislamientos), Candida albicans (26,5%), Candida tropicalis (24,5%), y otras especies de levaduras (16,4%). Los aislamientos de Candida fueron sensibles a los antifúngicos evaluados pero se detectaron, mediante el uso de curvas de letalidad, cepas tolerantes a la anfotericina B(AU)

Background. A retrospective study on the epidemiology of fungaemia due to yeasts of medical importance at the Hospital Nacional de Pediatría Prof. Dr. J. Garrahan, Buenos Aires was conducted between September 2001 and September 2003. Objectives. To learn the distribution of yeast species and to evaluate their in vitro antifungal susceptibility profile. Methods. The minimum inhibitory concentration (MIC) was determined according to the CLSI M27-A2 procedure, and time kill curves against amphotericin B were also performed. Results-Conclusions. The species isolated were Candida parapsilosis (32.6% of isolates); Candida albicans (26.5%), Candida tropicalis (24.5%), and other yeasts (16.4%). Candida isolates were susceptible to the antifungals evaluated, but amphotericin B-tolerant isolates were detected using time kill curves(AU)

[Epidemiology of fungaemia in a paediatric hospital of high complexity]. / Epidemiología de las fungemias en un hospital pediátrico de alta complejidad.

BACKGROUND: A retrospective study on the epidemiology of fungaemia due to yeasts of medical importance at the Hospital Nacional de Pediatría Prof. Dr. J. Garrahan, Buenos Aires was conducted between September 2001 and September 2003. OBJECTIVES: To learn the distribution of yeast species and to evaluate their in vitro antifungal susceptibility profile. METHODS: The minimum inhibitory concentration (MIC) was determined according to the CLSI M27-A2 procedure, and time kill curves against amphotericin B were also performed. RESULTS-CONCLUSIONS: The species isolated were Candida parapsilosis (32.6% of isolates); Candida albicans (26.5%), Candida tropicalis (24.5%), and other yeasts (16.4%). Candida isolates were susceptible to the antifungals evaluated, but amphotericin B-tolerant isolates were detected using time kill curves.

Tinea capitis. Experiencia de 2 años en un hospital de pediatría de Buenos Aires, Argentina / Tinea capitis: two years experience in a paediatric hospital of Buenos Aires, Argentina

La tiña de cabeza (tinea capitis) es una dermatofitosis causada por hongos pertenecientes a los géneros Microsporum y Trichophyton, y constituye un importante problema sanitario en Argentina. El objetivo fue conocer la incidencia y la respuesta terapéutica en los pacientes que asistieron a la consulta en un hospital pediátrico de alta complejidad durante un período de 2 años de estudio. Se diagnosticaron 98 casos de tinea capitis y 13 de querion de Celso. Microsporum canis se aisló en el 61,28% de los casos. El rango de los valores de concentración mínima inhibitoria para fluconazol, itraconazol, voriconazol, terbinafina, ketoconazol y griseofulvina fueron, respectivamente, > 32: 0,06–4; < 0,015–2; < 0,015–0,25; 0,13–8, y de 0,06–128mg/ml(AU)

Tinea capitis is an infection caused by dermatophytes of the genera Microsporum and Trichophyton, and constitutes a major health problem in Argentina. The aim of the present study was to find out the incidence of those etiological agents and the therapeutic response in patients attending a High-Complexity Paediatric Hospital within a two-year period. A total of 98 tinea capitis were diagnosed, 13 of which were Celsus kerion. Microsporum canis was isolated in 61.28%. The range of values for minimum inhibitory concentrations were >32, 0,06–4; <0,015–2; <0,015–0.25; 0.13–8; 0.06–128mg/mL for fluconazole itraconazole, voriconazole, terbinafine, ketoconazole and griseofulvin, respectively(AU)

[Tinea capitis: two years experience in a paediatric hospital of Buenos Aires, Argentina]. / Tinea capitis. Experiencia de 2 años en un hospital de pediatría de Buenos Aires, Argentina.

Tinea capitis is an infection caused by dermatophytes of the genera Microsporum and Trichophyton, and constitutes a major health problem in Argentina. The aim of the present study was to find out the incidence of those etiological agents and the therapeutic response in patients attending a High-Complexity Paediatric Hospital within a two-year period. A total of 98 tinea capitis were diagnosed, 13 of which were Celsus kerion. Microsporum canis was isolated in 61.28%. The range of values for minimum inhibitory concentrations were >32, 0.06-4; <0.015-2; <0.015-0.25; 0.13-8; 0.06-128 microg/mL for fluconazole itraconazole, voriconazole, terbinafine, ketoconazole and griseofulvin, respectively.

In vitro interactions of antifungal agents against clinical isolates of Fusarium spp.

The in vitro activities of amphotericin B (AMB), itraconazole (ITC), voriconazole (VCZ) and terbinafine (TBF) alone and in the combinations AMB+VCZ, TBF+ITC and TBF+VCZ were evaluated against 29 clinical isolates of Fusarium spp. (15 Fusarium solani, 7 Fusarium oxysporum, 2 Fusarium decemcellulare, 2 Fusarium dimerum and 3 other Fusarium spp.). Minimum inhibitory concentrations were determined using the method of the Clinical and Laboratory Standards Institute and the interaction activity was calculated using the fractional inhibitory concentration index. The four antifungal drugs tested alone showed very limited activity against most of the isolates. In contrast, the combination TBF+VCZ showed synergy for 21 isolates. The combination AMB+VCZ showed synergism for only five strains. No interaction or antagonism was observed among the remaining strains. TBF+ITC showed no interaction for 18 strains. The in vitro antifungal activity of the drugs alone and in combination varied for different species. These results corroborate previous in vitro studies in which the combination TBF+VCZ showed synergy against Fusarium spp., although further studies are needed to elucidate its potential usefulness for therapy.

Antifungal drug susceptibility profile of Pichia anomala isolates from patients presenting with nosocomial fungemia.

In vitro susceptibility of 58 isolates of Pichia anomala to five antifungal drugs using two broth microdilution methods (CLSI and EUCAST) was analyzed. Low susceptibility to itraconazole was observed. Fluconazole, voriconazole, amphotericin B, and caspofungin showed good antifungal activity, although relatively high drug concentrations were necessary to inhibit the isolates.

Synthesis and antifungal activity of (Z)-5-arylidenerhodanines.

An efficient microwave-assisted synthesis of new (Z)-5-arylidenerhodanines under solvent-free conditions is described and their in vitro antifungal activity was evaluated following the CLSI (formerly NCCLS) guidelines against a panel of both standardized and clinical opportunistic pathogenic fungi. An analysis of the structure-activity relationship (SAR) along with computational studies showed that the most active compounds (F- and CF(3)-substituted rhodanines) possess high logP values and low polarizability. Mechanism-based assays suggest that active compounds neither would bind to ergosterol nor would produce a damage to the fungal membrane.

Susceptibility patterns and molecular identification of Trichosporon species.

The physiological patterns, the sequence polymorphisms of the internal transcriber spacer (ITS), and intergenic spacer regions (IGS) of the rRNA genes and the antifungal susceptibility profile were evaluated for their ability to identify Trichosporon spp. and their specificity for the identification of 49 clinical isolates of Trichosporon spp. Morphological and biochemical methodologies were unable to differentiate among the Trichosporon species. ITS sequencing was also unable to differentiate several species. However, IGS1 sequencing unambiguously identified all Trichosporon isolates. Following the results of DNA-based identification, Trichosporon asahii was the species most frequently isolated from deep sites (15 of 25 strains; 60%). In the main, other Trichosporon species were recovered from cutaneous samples. The majority of T. asahii, T. faecale, and T. coremiiforme clinical isolates exhibited resistance in vitro to amphotericin B, with geometric mean (GM) MICs >4 mug/ml. The other species of Trichosporon did not show high MICs of amphotericin B, and GM MICs were <1 mug/ml. Azole agents were active in vitro against the majority of clinical strains. The most potent compound in vitro was voriconazole, with a GM MIC

G484S amino acid substitution in lanosterol 14-alpha demethylase (ERG11) is related to fluconazole resistance in a recurrent Cryptococcus neoformans clinical isolate.

Five sequential Cryptococcus neoformans isolates recovered from an AIDS patient with recurrent meningitis were analyzed. Four isolates were fluconazole susceptible, while the fifth isolate developed fluconazole resistance. Analysis of the 14-alpha lanosterol demethylase gene (ERG11) showed a point mutation in the resistant strain responsible for the amino acid substitution G484S.

Antifungal susceptibilities of Candida spp. isolated from blood in Spain and Argentina, 1996-1999.

The aim of this study was to identify retrospectively trends in species distribution and susceptibility patterns of Candida species causing bloodstream infections in 99 medical centres (55 in Spain and 44 in Argentina) from 1996 to 1999. A total of 744 Candida isolates were sent to the mycology reference laboratories during the study period (514 to the Spanish laboratory and 230 to the Argentinian laboratory). Candida non-albicans strains caused more episodes of fungaemia than Candida albicans isolates in both Spain and Argentina. C. albicans was isolated in 30.2% (155/514) and 40.9% (94/230) of episodes in Spain and in Argentina, respectively. In addition, Candida parapsilosis was the second most commonly isolated pathogen (36.4%). Candida tropicalis caused 13.7% of infections and Candida glabrata 7.4%. The amphotericin B MIC was

Transient fungemia caused by an amphotericin B-resistant isolate of Candida haemulonii.

A bloodstream infection due to Candida haemulonii afflicting a patient with fever and a medical history of megaloblastic anemia is reported. The clinical isolate was misidentified by the API 20C and VITEK identification systems. The results of susceptibility tests showed that the MIC of amphotericin B for C. haemulonii was 4 microg/ml. Additional susceptibility testing procedures based on the use of antibiotic medium 3 and Iso-Sensitest broth were performed, and killing curves were determined. Two collection strains of C. haemulonii were employed as controls. The three isolates exhibited resistance to amphotericin B in vitro regardless of the antifungal susceptibility testing method employed. In addition, the MICs of fluconazole for the three isolates were high. Further studies are needed in order to ascertain whether this species exhibits innate or acquired resistance to amphotericin B and other antifungal agents.