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Objective Identifying Fusarium isolates from mycosis symptomatic patients through molecular techniques as PCR and sequencing. Methods In this study, samples were taken from 101 mycosis symptomatic patients in-between 2004-2006. To determine isolates belonging to the Fusarium genus, the DNAr 28S region was amplified through PCR and specific PCR primers further confir-med their identity to the species level. Additionally, in order to confirm the identity of the species of the isolates, 75 isolates of these were analyzed by partial sequencing of the 28S rDNA and the TEF1-α gene. Results The 28S rDNA portion detected all 101 isolates as belonging to Fusarium and the PCR specific primers detected 52 and 29 isolates as F. oxysporum and F. solani, respectively; 34 and 41 of these, afterwards studied by partial sequencing of the 28S rDNA and TEF1-α genes respectively, were effectively identified by the technique. Conclusion From all the molecular markers used to identify Fusarium isolates, the sequence of the TEF1-α gene provided the best resolution in the identification of species level; however it is possible to discriminate between F. oxysporum and F. solani isolates by PCR, in most of the cases, what is important considering the simplicity of the technique and a faster diagnosis. RESUMEN: Objetivo Identificar aislamientos de Fusarium en pacientes con micosis por medio de las técnicas moleculares de PCR y secuenciación. Métodos Se tomaron 101 muestras de pacientes con micosis sintomática, entre los años 2004 y 2006. Para la detección de aislamientos como pertenecientes al género Fusarium, se amplificó parcialmente por PCR la región 28S del DNAr; y posteriormente —para la detección de la especie de Fusarium— se utilizaron cebadores específicos para F. oxysporum y F. solani. La verificación de la identidad de la especie de los aislamientos se hizo por secuenciación parcial de los genes 28S DNAr y TEF1-α. Resultados El total de 101 aislamientos fueron detectados como pertenecientes al género Fusarium utilizando un cebador universal de la region 28S DNAr; 52 y 29 aislamientos se detectaron como F. oxysporum o F. salani, respectivamente con los cebadores específicos, y la secuenciación parcial de los genes 28S rDNA o TEF1-α confirmó la identidad de las especies. Conclusión La secuenciación parcial del gen TEF1-α es aún el mejor marcador molecular para identificar aislamientos de Fusarium a nivel de especie. Sin embargo, en la mayoría de los casos es posible discriminar entre aislamientos de F. oxysporum y F. solani por PCR con cebadores específicos, lo que proporciona una ventaja importante considerando la simplicidad de la técnica y el rápido diagnóstico. COL0013709

Objective The aim of the present study was to evaluate the antifungal susceptibilities of isolates of Fusarium to amphotericin B, itraconazole and voriconazole. Methods The susceptibility of 44 isolates of Fusarium was tested by the E-test methodology. Results All the isolates were resistant to itraconazole, and 89 % and 54,5 % were resistant to amphotericin B and voriconazole, respectively. Discussion The results confirm the high level of resistance reported, regardless of the species or the strain of Fusarium involved. The high MICs level observed are worrying and suggest that new drugs are needed. RESUMEN : Objetivo Evaluar la susceptibilidad antifúngica in vitro de aislamientos de Fusarium a los antimicóticos amfotericina B, itraconazol y voriconazol. Métodos La susceptibilidad de 44 aislamientos clínicos de Fusarium fue evaluada por el método de difusión en disco, E-test. Resultados Todos los aislamientos fueron resistentes al itraconazol, y 89 % y 54,5 % fueron resistentes a la amfotericina B y al voriconazol, respectivamente. Discusión Los resultados confirman el alto nivel de resistencia reportado, independiente de la especie o la cepa de Fusarium involucrada. Los valores tan altos de MICs son preocupantes y sugieren la necesidad de evaluar nuevos medicamentos. COL0013709

Background: The yeasts species determination is fundamental not only for an accurate diagnosis but also for establishing a suitable patient treatment. We performed a concordance study of five methodologies for the species identification of oral isolates of Candida in Colombia. Methods: Sixty-seven Candida isolates were tested by; API® 20C-AUX, Vitek®2 Compact, Vitek®MS, Microflex® and a molecular test (panfungal PCR and sequencing). The commercial cost and processing time of the samples was done by graphical analysis. Results: Panfungal PCR differentiated 12 species of Candida, Vitek®MS and Microflex® methods identified 9 species, and API® 20C-AUX and Vitek®2 Compact methods identified 8 species each. Weighted Kappa (wK) showed a high agreement between Panfungal PCR, Vitek®MS, Microflex® and API® 20C-AUX (wK 0.62-0.93). The wK that involved the Vitek®2 Compact method presented moderate or good concordances compared with the other methods (wK 0.56-0.73). Methodologies based on MALDI TOF MS required 4 minutes to generate results and the Microflex® method had the lowest selling price. Conclusion: The methods evaluated showed high concordance in their results, being higher for the molecular methods and the methodologies based on MALDI TOF. The latter are faster and cheaper, presenting as promising alternatives for the routine identification of yeast species of the genus Candida.

Colombia currently does not have a specialised service for measuring antifungal levels in serum, which is of prime importance for the proper treatment and correct management of invasive fungal infections.To standardise and validate a simple, sensitive, and specific protocol, based on high performance liquid chromatography, complying with the parameters recommended by the Food and Drug Administration, to detect, identify, and quantify serum concentrations of posaconazole.A high performance liquid chromatography Agilent series-1 200 equipment was used with ultraviolet diode array detector and analytical column-Eclipse XDB-C18. Posaconazole-SCH56592 (batch IRQ-PAZ-10-X-103) was used as the primary control and itraconazole (batch ZR051211PUC921) was used as an internal control. The validation was performed taking into account all criteria recommended by the Food and Drug Administration (selectivity, calibration curves, recovery, accuracy, precision, sensitivity, reproducibility, and stability of the sample).The most suitable chromatographic conditions were the following: column temperature 25°C, ultraviolet detection at 261nm, 50μl injection volume, flow volume 0.8ml/min, 10min running time, mobile phase of acetonitrile:water (70:30), and final retention times of 3.4 and 7.2min for posaconazole and itraconazole, respectively, with a wide and reliable quantification range (0.125μg/ml to 16μg/ml). Using these parameters, the method was selective, RThe selectivity and chromatographic purity of the obtained signal, as well as the standardised limits of detection and quantification, make this method an excellent tool for therapeutic monitoring of patients treated with posaconazole.

In paracoccidioidomycosis (PCM), the primary lung infection remains silent. In this study, attempts were done to define the primary target organ by correlating lung radiographic abnormalities with the time course of mucosal/skin lesions concurrently exhibited at diagnosis by 63 patients in whom microscopy and/or isolation of Paracoccidioides brasiliensis from respiratory secretions had been positive. Mucosal and skin lesions were found in 65.1% and 12.7% of the patients, respectively. Odynophagia and dysphagia were present in 38.1% each. All patients had lung interstitial infiltrates, and 31.7% had also alveolar lesions; fibrosis was recorded in 46% of them. An inverse correlation was shown for fibrosis and presence of either odynophagia or dysphagia. Cluster analyzes strongly supported two sets of patients: those with mucosal damage, odynophagia/dysphagia, and alveolo-interstitial infiltrates and those with dermal lesions, dyspnea, and lung fibrosis. These groups may represent novel stages in the natural course of PCM.

It is known that peritoneal murine macrophages activated with interferon-gamma exert a fungicidal effect against Paracoccidioides brasiliensis conidia by a nitric oxide (NO)-mediated mechanism. This NO-mediated effect can also be induced by other cytokines such as tumor necrosis factor-alpha (TNF-alpha). The aim of this study was to determine if TNF-alpha-activated peritoneal murine macrophages infected with P. brasiliensis were able to show fungistatic/fungicidal effects mediated by NO. The results indicated that although macrophage activation with TNF-alpha did not result in NO production, these cells played an important role in inhibiting the conidia from becoming yeast cells. In vivo, the NO-independent inhibitory effect would prove of importance for the establishment of P. brasiliensis in host tissues.

Interferon gamma (IFN-V) is a cytokine produced by cells from the immune system, such as T-cells and natural killer (NK) cells. This molecule has several effects on macrophage (MO) activities including stimulation of the respiratory burst and in vitro enhancement of antimicrobial activity of Mės against bacterial, fungal and mycobacterial organisms. It is known that peritoneal murine Mos, once activated with IFN-Y, exert a fungicidal effect against some pathogenic fungi, including Paracoccidioides brasiliensis, and that this mechanism is mediated by nitric oxide (NO). In addition, it has been demonstrated that IFN-Y is important in the in vivo control of certain mycotic infections. Our purpose was to determine if in vitro, IFN-y-activated peritoneal murine Mos participate in the production of both nitric oxide (NO) and TNF-a, and if the corresponding mechanisms implicated the inducible nitric oxide synthase (iNOS) and nuclear factor (NF-KB) expression. The results showed that the IFN-Y-activated Mos had an increase in both NF KB and iNOS expressions at 6 and 18 h, respectively, indicating a high NO production but a non-detectable TNF-a production. These data suggest that NF-KB expression preceded iNOS expression, inducing both high NO production and IFN-y-activation. Apparently, the latter cytokine by itself is not sufficient to induce TNF-a production on peritoneal murine MOs. COL0013709