Biofilms, Infection, and Parenteral Nutrition Therapy

Abstract

Parenteral nutrition therapy is used in patients with a contraindication to the use of the gastrointestinal tract, and infection is one of its frequent and severe complications. The objective of the present study was to detect the presence of biofilms and microorganisms adhering to the central venous catheters used for parenteral nutrition therapy by scanning electron microscopy. Thirty-nine central venous catheters belonging to patients with clinical signs of infection (G1) and asymptomatic patients (G2) and patients receiving central venous catheters for clinical monitoring (G3) were analyzed by semiquantitative culture and scanning electron microscopy. The central venous catheters of G1 presented more positive cultures than those of G2 and G3 (81% vs 50% and 0%, respectively). However, biofilms were observed in all catheters used and 55% of them showed structures that suggested central venous catheters colonization by microorganisms. Approximately 53% of the catheter infections evolved with systemic infection confirmed by blood culture. The authors conclude that the presence of a biofilm is frequent and is an indicator of predisposition to infection, which may even occur in patients who are still asymptomatic.

Estudo Comparativo De Hemoculturas E Cateteres Positivos Para Leveduras Do Gênero Candida De Origem Hospitalar

“…No que se refere à prevalência de microrganismo, tanto em CVC quanto CVC juntamente com hemocultura, as leveduras aparecem em segundo lugar na colonização de cateter e, em terceiro lugar, na infecção sanguínea relacionada ao CVC (MACHADO et al, 2009). Na utilização do CANDIFAST para identificação de leveduras, obteve-se um baixo índice de identificação, cerca de 14%, pois, por se tratar de um método colorimétrico, sua leitura é subjetiva e nem sempre as mudanças de coloração são precisas e reprodutíveis, além de o tempo médio de obtenção de resultado ser de 24 a 48 horas (PEREIRA, 2010).…”

“…Já, ao executar a metodologia automatizada VITEK® 2 Compact, foi possivel identificar 82% das amostras em um tempo médio de 18 horas, o que demonstra o bom desempenho do método (PÁROLA, 2011;PEREIRA, 2010). Na análise das imagens obtidas pela Microscopia Eletrônica de Varredura, pôde-se observar a presença de biofilme em 100% das amostras, portanto, apesar da tecnobioengenharia existente na fabricação de CVC, eles ainda estão susceptíveis a formação de biofilme, fato de extrema preocupação, pois contribui para o aumento da morbidade de pacientes que carecem utilizar esses materiais (MACHADO et al, 2009;MACHADO, 2010).…”

“…Em duas amostras de CVC e hemocultura do mesmo paciente, verificou-se de concordância entre os micro-organismos presentes, comprovando que o sítio de inserção do cateter está diretamente relacionado com a formação de biofilme e contribuem para a manutenção e surgimento do processo infeccioso sistêmico (MACHADO et al, 2009).…”

Nutritional status and hyperglycemia in the peritransplant period: a review of associations with parenteral nutrition and clinical outcomes

“…According to Sheean et al, PN has inherently greater risks of infections when compared with EN or standard oral diets, and because of its adverse consequences, several authors have challenged the intuitive conclusion that PN is beneficial and necessary during HSCT 14 . A higher risk of catheter-related bloodstream infections in PN recipients is well described in the literature 54 as the micro- and macronutrient composition of PN can facilitate the growth of microorganisms 55 . Furthermore, it has been suggested that these infectious complications could also be related to bacterial translocation due to atrophy of the gut mucosa and gut-associated lymphoid tissue, as a consequence of PN or absence of EN 56 .…”

Parenteral Nutrition

“…Because of a relatively low pH, PN formulations containing only dextrose and amino acids seem to inhibit the growth of most microbes, with the exception of fungi. 46,47 Dextrose-containing fluids also promote some Candida species to produce biofilm similar to that of their bacterial counterparts, potentially explaining the increased proportion of CLABSIs caused by fungal pathogens among patients receiving PN. 41,42 There is also some evidence that IVLEs suppress immune function, thus further increasing the risk for infection.…”