临床微生物实验室药敏纸片片间均匀性差异的实时监测和药敏质控试验频率的动态调整

Methods for constantly monitoring the uniformity difference between susceptibility discs and dynamically adjusting the quality control frequency of antimicrobical susceptibility testing in clinical microbiology laboratory

目的在临床微生物实验室,建立对药敏纸片质量和片间均匀性差异进行实时监测,并对药敏质量控制试验频率进行动态调整的参考方法。方法通过多纸片重复试验和MIC测定对3种少见药敏谱和4种不合理药敏模式进行研究和分析,寻找其产生的内在原因。结果当重复药敏试验与初次药敏试验结果不一致,且重复试验药敏纸片间抑菌圈直径最大值与最小值的差大于3mm时,提示为该药敏纸片片间均匀性差异太大,需更换批次、批号并与厂家联系;当重复药敏试验与常规药敏试验结果不一致,且重复试验药敏纸片间抑菌圈直径最大值与最小值的差小于等于3mm时,提示需对药敏质量控制试验频率进行动态调整。结论那些非"少见药敏谱或不合理药敏模式"的药敏结果也同样存在药敏纸片质量问题和片间均匀性差异问题,且在日常工作中更难以发现。每家实验室都应根据自身的特点和具体情况,制定相应的方案,对药敏纸片质量和片间差进行时时监测,对质量控制试验频率进行动态调整,以确保实验的准确性和可重复性。

Objective To establish reference methods to constantly monitor the quality and uniformity difference of antimicrobial susceptibility discs and also to dynamically adjust the frequency of susceptibility quality control test in Clinical Microbiology Laboratory. Methods To conduct research and analysis through multi- discs measurement and MIC test in order to find the underlying causes of three rare antimicrobial resistance and four unreasonable antimicrobial susceptibility patterns. Results When repeated susceptibility test results are not consistent with the initial susceptibility test results, and the gap between the maximum and minimum of inhibition zone diameter of repeated susceptibility discs exceeds 3mm, it reveals that the uniformity difference among susceptibility discs is so apparent that they need to be replaced by batch and lot number and the manufacturer should be contacted; when repeated susceptibility test results are not consistent with conventional susceptibility test results, and the gap between the maximum and minimum of inhibition zone diameter of repeated susceptibility discs is no more than 3mm, it reveals that frequency of quality control test of susceptibility should be dynamically adjusted. Conclusions Susceptibility disc quality issues and the uniformity difference issues also exist in non ＂rare antimicrobial resistance or unreasonable susceptibility patterns＂, and they are more difficult to detect in daily work. Based on own characteristics and specific circumstances, each laboratory should develop appropriate solutions to constantly monitor quality and uniformity difference of susceptibility discs and to dynamically adjust the frequency of quality control test, as a way to ensure the accuracy and repeatability of experiments.