ABSTRACT
Background: Non albicans species are emerging increasingly as significant ICU pathogens. The increasing incidence of C. tropicalis infections is a significant problem because of its ability to develop rapid resistance to fluconazole.Methods: The study was designed to isolate, evaluate the risk factors and outcome of C. tropicalis infection from intensive care units. Identification was done by the biochemical methods. A total of 89 patients culture positive for C. tropicalis were selected for retrospective analysis over a period of one year. We collected various data about risk factors and outcome from the medical records.Results: A total of 89 patients culture positive for Candida tropicalis were analysed. Majority of these culture isolates were obtained from their blood (59.55%) followed by urine samples (31.46%). The indwelling devices (93.2%) remained a highest risk followed by prolonged administration of antibiotic therapy (92.1%) and admission in ICU for more than a week (88.8%). Overall mortality rate was 31.5%. Mortality was higher in patients with longer total length of stay in hospital (89.3%; p 1.000), indwelling devices (85.7%; p 0.5663) and in whom the antimicrobial therapy was administered for prolonged duration (82.1%; p 0.7581), although these factors remained statistically insignificant. 92.1% of isolates were sensitive to amphotericin B and showed 52.8%; 9.0% sensitivity to itraconazole and fluconazole respectively.Conclusions: C. tropicalis is now classified as the third or fourth NAC species being commonly isolated from clinical samples and associated with persistent systemic infections leading to a longer stay in the hospital. Several virulence factors seem to be responsible for high dissemination and mortality.
ABSTRACT
The fungi of the genus Candida play a relevant role in the emergence of oral infections and are increasingly more frequent the cases of infections by non-albicans strains. In light of this context and the need for new alternatives to the antimicrobial therapy, the monoterpene [7-hidroxicitronelal] (7-HO) was evaluated for its antifungal effects. For the obtainment of the MIC and MFC values the broth microdilution method was used. The MIC and the MFC of this monoterpene for 60% of the tested strains was of 256µg/mL and 512µg/mL respectively. Furthermore, the standard antifungal nystatin (100UI/mL) was used as positive control for the inhibition of fungal growth. Therefore, were used 4 clinical strains of the species tropicalis (LM 06, LM 14, LM 31 and LM 36) and a standard strain (C. tropicalis ATCC 13803), originated from the Mycology collection of the Mycology Laboratory (LM) of the Health Sciences Center (CCS) of the Federal University of Paraiba (UFPB). The results obtained in this study showed fungicide activity of the compound (7-OH) against the strains of C. tropicalis.
Os fungos do gênero Candida tem um papel relevante no aparecimento de infecções orais e são cada vez mais frequentes os casos de infecções por cepas não-albicans. Diante deste contexto e da necessidade de novas alternativas para a terapia antimicrobiana, o monoterpeno [7-hidroxicitronelal] (7-HO) foi avaliado pelos seus efeitos antifúngicos. Para a obtenção dos valores da CIM e da CFM foi utilizado o método da microdiluição em caldo. A CIM e a CFM deste monoterpeno para 60% das cepas testadas foram de 256µg/mL e 512µg/mL respectivamente. Além disso, o antifúngico padrão nistatina (100UI/mL) foi utilizado como controle positivo para inibir o crescimento fúngico. Por tanto, foram utilizadas 4 cepas clínicas da espécie tropicalis (LM 06, LM 14, LM 31 e LM 36) e uma cepa padrão (C. tropicalis ATCC 13803), oriundas da Micoteca do Laboratório de Micologia (LM) do Centro de Ciências da Saúde (CCS) da Universidade Federal da Paraíba (UFPB). Os resultados obtidos neste estudo mostraram atividade fungicida do composto (7-OH) contra as cepas de C. tropicalis.
Subject(s)
In Vitro Techniques , Candidiasis, Oral , Monoterpenes , Antifungal AgentsABSTRACT
Background: C.tropicalis is an important cause of nosocomial infections particularly in immunocompromised patients. Infections caused by Candida spp. are often associated with biofilm formation on implanted medical devices or on epithelial cell surfaces. Phenotypic characteristics of sessile cells in biofilms are known to be different from those of their free-living, planktonic counterparts. Biofilm forming strains often show increased resistance to antimicrobial agents. Materials and Methods : We measured susceptibility to fluconazole of fifty C.tropicalis isolates from immunocompromised (29) and immunocompetent (21) patients by minimum inhibitory concentration (MIC) and minimum biofilm inhibitory concentration (MBIC) assays. MBIC was done using the calorimetric indicator resazurin, to measure the metabolically active cells. Results : Biofilm forming cells showed increased resistance to fluconazole. Conclusion : The resazurin dye test was found to be a good method for determining MBIC.