Koshigaya Ohbukuro Clinic.
Department of Microbiology and Immunology, Nippon Medical School.
J Microorg Control. 2023;28(3):69-75. doi: 10.4265/jmc.28.3_69.
Bedside dialysis monitoring equipment for hemodialysis are located in the bioburden section upstream of the endotoxin-retentive filter for dialysis fluid sterilization. We observed 26 equipment at our institution for bacterial contamination at least once every 4 weeks for 5 years with another ultrafiltration membrane upstream to prevent bacterial contamination. Bacterial contamination levels were highest and most diverse at the time of the first flush. During subsequent initial cleanng, the contamination level decreased, and bacterial species converged almost exclusively to one genus, namely Methylobacterium spp. During clinical use, the equipment were cleaned and disinfected daily after dialysis, and daily operations and maintenance were performed using aseptic techniques. Although the frequency of bacterial detection decreased annually, the same bacterial genotypes observed at the first flush were isolated even after long time periods and were thought to persist in the equipment possibly by forming biofilm. Pseudomonas aeruginosa was newly detected after the replacement of parts during breakdown maintenance, indicating the need to sterilize replacement parts. Thus, the bioburden should be assessed regularly as part of the management of in-house-produced dialysis fluid.
血液透析的床边透析监测设备位于用于透析液灭菌的内毒素截留过滤器的生物负荷部分的上游。我们在机构内观察了 26 台设备，每 4 周至少观察一次细菌污染情况，另外在上游还有一个超滤膜，以防止细菌污染。在第一次冲洗时，细菌污染水平最高且最多样化。在随后的初始清洁过程中，污染水平下降，细菌种类几乎完全收敛到一个属，即甲基杆菌属。在临床使用过程中，设备在透析后每天进行清洁和消毒，并且每天使用无菌技术进行操作和维护。尽管细菌检测的频率逐年下降，但即使在很长一段时间后，仍会分离出与第一次冲洗时相同的细菌基因型，这可能是因为它们形成了生物膜而在设备中持续存在。在故障维护期间更换部件后，新发现了铜绿假单胞菌，表明需要对更换部件进行消毒。因此，应定期评估生物负荷，作为内部生产的透析液管理的一部分。
