On the reading of cultures
I went into the Micro lab this afternoon, and found two things of note: first, even though there was a practical question dealing with the proper discarding of cultures that essentially everyone got correct, in practice people seem to miss what the proper procedure is. All to-be-discarded culture tube need to go in the appropriate rack, with all tape removed prior to discard. Second, I found about a dozen and a half cultures in the incubator Sunday afternoon. I have removed them, and all cultures that were in the incubator over the weekend will need to be run again.
All of our cultures need to be run, incubated, and interpreted according to specific guidelines, or else the interpretation of the culture is completely invalid. The Clinical and Laboratory Standards Institute is a national organization that establishes guidelines for the proper way to set up and read clinical assays in laboratories. If a test is run for too short of an interval, there is a significant possibility of obtaining a false negative result, and if a test is run for too long of an interval, there is a possibility of obtaining a false positive result. Either case represents the possibility of a poor patient outcome: for the false negative, they might not receive notice that they have a given infection, and for the false positive, they might be started on an inappropriate treatment regimen.