Fungi in dialysis water and dialysate: occurrence, susceptibility to antifungal agents and biofilm production capacity.

The aim of this study was to investigate the occurrence of fungi in dialysis water and dialysate, in addition to evaluating the susceptibility to antifungals and the biofilm production capacity of isolated microorganisms. The samples were collected in three hemodialysis units in Bauru (Brazil), every 15 days (July 2017-June 2018) at post-reverse osmosis, reuse, and dialysate points. The fungi were isolated by spread plate on Sabouraud dextrose agar. Filamentous fungi were phenotypically identified and yeasts were subjected to molecular evaluation of the ITS region. Susceptibility test to antifungals was carried out by the broth microdilution method and biofilm production capacity was evaluated in microtiter plates using crystal violet staining. Fungi were isolated in 52/216 (24.1%) samples, with an average count of 16.3 (10-40) CFU/mL. Overall, 61 microorganisms were identified, with 54 (88.5%) filamentous fungi and 7 (11.5%) yeasts. The main genera included were Penicillium, Cladosporium, Scedosporium, Rhinocladiella, Fusarium, and Emmonsia. Most isolates showed high values of minimum inhibitory concentration for 5-flucytosine and fluconazole and 35/45 (77.8%) isolates were classified as strong producers of biofilm. In order to increase the safety of the dialysis process, the adoption of control measures and monitoring of fungi in hemodialysis fluids is suggested.

Fungi in dialysis water and dialysate: occurrence, susceptibility to antifungal agents and biofilm production capacity

The aim of this study was to investigate the occurrence of fungi in dialysis water and dialysate, in addition to evaluating the susceptibility to antifungals and the biofilm production capacity of isolated microorganisms. The samples were collected in three hemodialysis units in Bauru (Brazil), every 15 days (July 2017­June 2018) at post-reverse osmosis, reuse, and dialysate points. The fungi were isolated by spread plate on Sabouraud dextrose agar. Filamentous fungi were phenotypically identified and yeasts were subjected to molecular evaluation of the ITS region. Susceptibility test to antifungals was carried out by the broth microdilution method and biofilm production capacity was evaluated in microtiter plates using crystal violet staining. Fungi were isolated in 52/216 (24.1%) samples, with an average count of 16.3 (10­40) CFU/ mL. Overall, 61 microorganisms were identified, with 54 (88.5%) filamentous fungi and 7 (11.5%) yeasts. The main genera included were Penicillium, Cladosporium, Scedosporium, Rhinocladiella, Fusarium, and Emmonsia. Most isolates showed high values of minimum inhibitory concentration for 5-flucytosine and fluconazole and 35/45 (77.8%) isolates were classified as strong producers of biofilm. In order to increase the safety of the dialysis process, the adoption of control measures and monitoring of fungi in hemodialysis fluids is suggested.

Fluoretação das águas de abastecimento público: 10 anos de monitoramento em 38 municípios do Centro-Oeste Paulista, São Paulo, Brasil / Public water supply fluoridation: 10 years of monitoring in 38 municipalities of Centro-Oeste Paulista, São Paulo, Brazil

Introdução: No estado de São Paulo, a concentração de flúor na água de abastecimento público deve ser mantida na faixa de 0,6 a 0,8 mg/L, a fim de prevenir a cárie e evitar o risco de fluorose. Objetivo: Avaliar a concentração de fluoretos na água de abastecimento público dos municípios de abrangência do Grupo de Vigilância Sanitária de Bauru. Método: Os dados foram extraídos da rotina do Instituto Adolfo Lutz ­ Bauru e oriundos de 38 municípios monitorados pelo Programa de Vigilância da Qualidade da Água para Consumo Humano (Proágua), no período de 2007­2016. As análises laboratoriais foram realizadas utilizando-se o método potenciométrico com eletrodo íon-seletivo e a interpretação dos resultados baseou-se na Resolução SS nº 250/95 e na classificação proposta pelo Centro Colaborador do Ministério da Saúde em Vigilância da Saúde Bucal (CECOL). Resultados: Das 8.887 amostras analisadas, 31,1% apresentaram teores inadequados de íons fluoretos, sendo que 22,7% estavam abaixo e 8,4% acima do limite estabelecido pela legislação. De acordo com a proposta do CECOL, 59,4% das amostras exibiram benefício máximo para prevenção de cárie e 0,6% revelaram risco muito alto para produção de fluorose dentária. Conclusões: Tais dados apontam a necessidade de aprimorar o controle operacional do processo de fluoretação e enfatiza a importância da vigilância da qualidade da água.

Introduction: In the State of São Paulo, the concentration of fluoride in the public water supply should be maintained in the range of 0.6 to 0.8 mg/L, in order to prevent caries and avoid the risk of fluorosis. Objective: To evaluate the concentration of fluoride in public water supply in the municipalities covered by the Bauru Sanitary Surveillance Group. Method: Data were extracted from the routine of the Adolfo Lutz Institute ­ Bauru, from 38 municipalities monitored by the Proágua Program, in the period 2007­2016. Laboratory analyses were performed using the potentiometric method with ion-selective electrode and the interpretation of the results was based on Resolution SS-250/95 and the classification proposed by the Collaborating Center of the Ministry of Health in Oral Health Surveillance (CECOL) Results: Of the 8,887 samples analyzed, 31.1% had inadequate levels of fluoride ions, with 22.7% being below and 8.4% above the limit established by the legislation. According to the CECOL proposal, 59.4% of the samples showed maximum benefit for caries prevention and 0.6% revealed a very high risk for the production of dental fluorosis. Conclusions: These data point out the need to improve the operational control of the fluoridation process and emphasize the importance of water quality surveillance.