Faintuch J, Battaglia C, Dias M C, Maluf F, Libanori H T, Leme R B, Faintuch B L, Maculevicius J, Pinotti H W
Grupo de Nutrição da Disciplina de Cirurgia do Aparelho Digestivo, Hospital das Clínicas da Faculdade de Medicina da USP.
Rev Hosp Clin Fac Med Sao Paulo. 1990 Nov-Dec;45(6):248-52.
The gastrointestinal tract is comparatively resistant to food-born germs, but recent studies suggest that nosocomial infections may be triggered by this route. In a study with industrialized diets, prepared with aseptic technique and stored up to 24 hours, aerobic and anaerobic contaminants were searched. Samples were taken after 0.8 and 24 hours, whereas half of these last two analyses were carried out in material left at room temperature, and the other half in refrigerated diets. Initial examination revealed 50% of positive cultures, but part of this was due to non-pathogenic Bacillus germs. After 8 and 24 hours 90% of the samples grew organisms, again with a large proportion of Bacillus, but also with several Gram-negative bacteria, as well as rare Gram-positives. Diarrhea and fever were not registered in patients submitted to enteral nutrition during the study period, nor could any episodes of bacteremia or septic shock be attributed to contaminated feeding material. This lack of clinical consequences of the reported bacterial isolations is not unexpected, and suggests that low concentrations of microorganisms were probably present in the preparations, below a critical level. Nevertheless, attention will be required in the future for better quality control of enteral nutrition mixtures, specially when resistant strains of Gram-negative species are identified, and also in the management of debilitated or immunologically compromised hosts.
胃肠道对食源性病原体具有相对抗性,但最近的研究表明,医院感染可能通过这条途径引发。在一项针对工业化饮食的研究中,采用无菌技术制备并储存长达24小时,检测需氧和厌氧污染物。在0.8小时和24小时后取样,后两次分析中的一半在室温下留存的材料中进行,另一半在冷藏饮食中进行。初步检查显示50%的培养物呈阳性,但部分原因是由于非致病性芽孢杆菌。8小时和24小时后,90%的样本培养出微生物,同样有很大比例的芽孢杆菌,还有几种革兰氏阴性菌以及罕见的革兰氏阳性菌。在研究期间接受肠内营养的患者中未记录到腹泻和发热,也没有任何菌血症或感染性休克发作可归因于受污染的喂养材料。所报告的细菌分离缺乏临床后果并不意外,这表明制剂中可能存在低浓度的微生物,低于临界水平。然而,未来需要对肠内营养混合物进行更好的质量控制,特别是当鉴定出革兰氏阴性菌的耐药菌株时,以及在体弱或免疫功能低下宿主的管理中也需要加以关注。