Quality of dialysis water and dialysate in haemodialysis centres: Highlight for occurrence of non-fermenting gram-negative bacilli.

AIMS: To evaluate the physicochemical and microbiological quality of dialysis water and dialysate samples from haemodialysis centres. METHODS AND RESULTS: Samples were fortnightly collected from three haemodialysis centres in Bauru City, Brazil, between July 2017 and June 2018, at the stages of post-reverse osmosis, reuse and dialysate. Analyses included determination of conductivity, fluoride, nitrate and sulphate; test for total coliform bacteria; count of heterotrophic bacteria; count and identification of non-fermenting gram-negative bacilli (NFGNB); drug susceptibility test; biofilm formation capacity; and genetic similarity among some isolated NFGNB. Of the analysed samples, only 4/72 (5.6%) had conductivity values ≥10 mS/cm, 4/216 (1.9%) presented total coliforms and 1/216 (0.5%) had heterotrophic bacteria count >100 CFU/ml. NFGNB were isolated from 99/216 (45.8%) samples, and the major identified micro-organisms included Herbaspirillum aquaticum/huttiense, Brevundimonas aurantiaca, Cupriavidus metallidurans, Pseudomonas aeruginosa and Ralstonia insidiosa. Isolates of P. aeruginosa and Burkholderia cepacia complex were sensitive to most antimicrobials and, together with isolates of Ralstonia insidiosa and Ralstonia pickettii, showed strong biofilm formation capacity. Some isolates expressed the same electrophoretic profile on pulsed-field gel electrophoresis, indicating the persistence of bacterial clones in the systems over time. CONCLUSIONS: NFGNB were observed in several dialysis water and dialysate samples from all investigated centres, which may represent a risk to the health of patients. SIGNIFICANCE AND IMPACT OF THE STUDY: Regular inclusion of actions for NFGNB control and monitoring in haemodialysis fluids are suggested for greater safety of the dialytic process.

Diagnóstico laboratorial da coqueluche: freqüência do isolamento de Bordetella pertussis de amostras clínicas, por meio da técnica de cultura realizada nos laboratórios regionais do Instituto Adolfo Lutz, São Paulo, Brasil / Pertussis diagnosis: frequency of Bordetella pertussis detection from clinical samples by the culture method performed at regional laboratories of the Instituto Adolfo Lutz, São Paulo, Brazil

A coqueluche é uma doença respiratória infecciosa aguda, causada por Bordetella pertussis, cocobacilos Gram-negativos fastidiosos com requisitos nutricionais complexos. Recentemente foi descrito em vários países o aumento do número de casos da doença - com o acometimento de populações vacinadas - e da sua incidência em adolescentes e adultos. No Brasil, a coqueluche só se tornou doença de notificação compulsória a partir de 2001. O presente trabalho avaliou o índice de positividade no diagnóstico da coqueluche por meio da técnica de cultura de secreção de nasofaringe, realizada segundo Regan e Lowe, 1997, e também a sua freqüência em diferentes faixas etárias, nas regiões de abrangência dos Laboratórios Regionais do Instituto Adolfo Lutz, São Paulo, SP, no período de 2001 a 2005. Os resultados mostraram aumento no número de amostras positivas a partir de 2004, o que pode ter ocorrido em função da maior conscientização dos profissionais envolvidos na investigação e notificação da doença.O maior número de amostras positivas deu-se na faixa etária de 0 a 6 meses (65,0%), com predomínio da faixa de 1 a 3 meses. A taxa de positividade em adolescentes e adultos foi de 19,4%. Os dados obtidos são relevantes para a melhoria do diagnóstico da coqueluche na região estudada e indicam a necessidade de informações adicionais para dar suporte às estratégias de prevenção e prover um melhor entendimento da doença no país.

Pertussis or whooping cough is an acute respiratory infectious disease caused by Bordetella pertussis, a small Gram-negative coccobacillus which has complex nutritional requirements. Several countries have recently reported an increase in pertussis in immunized populations, accompanied by a significant increase among adolescents and adults. In Brazil, pertussis had its epidemiological surveillance established only in 2001. This study evaluated the indices of positivity on culture method performed according to Regan & Lowe, 1997, for pertussis diagnosis in the regions enclosed by the regional laboratories of the Instituto Adolfo Lutz - São Paulo state, Brazil, from 2001 to 2005. An increase in the number of positive samples was observed since 2004, which could be due to a better identification of the disease by health workers involved on its investigation, diagnosis, and notification. According to these results, the young infants presented the highest positivity rate (age 0-6 months, 65.0%). The older age groups (adolescents and adults) showed 19.4% of positivity. These data are relevant for monitoring pertussis diagnosis and for conducting epidemiological studies in the studied regions, and also to provide support to prevention programs.