Positive Biologicals 3m 3 hour test

[wbenitez]

Has anyone been experiencing issues with positive biologicals for the three hour read out. In particular, false positive biologicals.

[jrc]

Are you meaning for steam or ETO?

[wbenitez]

I am referring to 3 hour biologicals for Steam

[wbenitez]

Are you meaning for steam or ETO?


I am referring to the 3 hour rapid read out for Steam

[edbaker]

wbenitez - please be sure that you have your 3-M rep and your facitlity maintenance person involved in theses types of ocurrences. We have had that concern a couple of times, but after all the investigation was completed our steam steilizer showed that it had an air leakage problem. Actually after all testing was completed there were three air leaks in one of our sterilizers. Once the air leakage problem was rectified the false positive problem disappeared as well. Other then that concern with the biologicals I have not heard of any other occurrences with false positive biologicals. I hope this helps and let me know what happens with your investigations. Your 3-M rep will also give you another auto reader to make sure the problem doesn't lie within the auto reader itself. They will send the first auto reader in for testing to make sure that it is working properly. As I stated let me know what happens.............take care.

[wbenitez]

We have looked and/or found the following in order to narrow down to a possible cause.

1. Leaks, temp and pressure have been consistently adequate, The Steam was tested through an outside company and its quality determined to be good.

2. Our bowie dick test have been consistent

3. The biologicals have consistently been negative to the spore upon further incubation, followed by our lab in futher testing as outlined by the manufacturer. Which means they all have been false positives. Only on one ocassion the bateria grown during further incubation was determined to be other than the corect spore.

3. No trends have been identified in terms of staff processess and/or specific sterilization equipment among three that are in operation.

4. The incidents have diminished however they seem to reapear every few weeks.

5. We have re-educated the staff since my last theory is that the staff was not properly handling those post sterilization, although, as I stated, no trends have been identified.

6. Our class five integrators have consistently pass the challenge.

[Uprooted Scrub]

Hi...

Is it possible you might have a problem with your incubator?

Interestingly enough, I sent my 290 (3 hour 3M RRBI) incubator back to 3M for repair today. We're not getting false positives, but we've been getting false negatives for our control BIs. When we put unprocessed BIs in the incubator, the flourescence process tell us the BI is negative, but when we let the BI 'grow out' for 3 hours, it changes color. I called 3M to see about a possible bad lot of BIs, and they currently have no recalls out. I figure it's a problem with the bulb...

Good luck, and hope this helps.

Blaine

[wbenitez]

Yes. That was one of the first things that was done. And the amount of false positives did diminished some but was not completetly erradicated.

[wbenitez]

Additionally, the old incubator was sent for evaluation and nothig was found. We do not use the one with the SUV light.

[sonny1388]

There are a couple of other things you can look at to try to determine the cause. Do you have more than one autoclave? Are all of the false positives coming from the same autoclave? Yes....probably not false positives, but a problem with the sterilizer. No...probably a problem with either the biologicals, the tester, or handling of the tests prior to incubation. Assuming that they are coming from more than one autoclave, here are a couple more... Do you have more than one reader? Are they all showing false positives? If you only have one, it might be worth borrowing one from 3M to help determine the problem. Are there sets of false positives coming from the same lot numbers i.e. 3 from one lot, none from the next two, 5 from the next. This may indicate a problem with a particular set of lot numbers. Are the BI's being handled properly? Are they being allowed to cool before popping? Some overly hot BI's will "boil" and may become contaminated if the liquid penetrates the top filter. Another way to check this is to ask your lab to determine what bugs are present in the BI. The bugs used in 3M BI's are G. stearolmophilis, so if they find anything else, it is due to improper handling. Do the BI's change color after 24 hrs? It is not a false positive if the medium changes, it is a true positive, and indicates a problem with the sterilizer. Let me know if this helps, and the results, and I'll see if I can't come up with some more.

[sonny1388]

BTW, we have not had any problems with the BI tests at our hospital

[wbenitez]

There are a couple of other things you can look at to try to determine the cause. Do you have more than one autoclave? We own 3. Are all of the false positives coming from the same autoclave? No. No particular trends exist. No...probably a problem with either the biologicals, the tester, or handling of the tests prior to incubation. The tester have been checked and no preblem identifed. New tester has been in place for a few months.Assuming that they are coming from more than one autoclave, here are a couple more... Do you have more than one reader? No. Are they all showing false positives? Yes. If you only have one, it might be worth borrowing one from 3M to help determine the problem. Done. Are there sets of false positives coming from the same lot numbers i.e. 3 from one lot, none from the next two, 5 from the next. No. This may indicate a problem with a particular set of lot numbers. Are the BI's being handled properly? May have not been handled properly in the past. . The staff have been re-educated. Are they being allowed to cool before popping? Some overly hot BI's will "boil" and may become contaminated if the liquid penetrates the top filter. Another way to check this is to ask your lab to determine what bugs are present in the BI. This has been done. Only one time a different organism was found. The bugs used in 3M BI's are G. stearolmophilis, so if they find anything else, it is due to improper handling. Do the BI's change color after 24 hrs? No they are not turning. It is not a false positive if the medium changes, it is a true positive, and indicates a problem with the sterilizer. Let me know if this helps, and the results, and I'll see if I can't come up with some more.[/QUOTE]We are in the process of having the equipment tested to monitor interior conditions during actual cycles at various times.

Thanks for all of your comments.

[Chuck Hughes]

3M warns users in their literature and seminars that "false positives" can occur if the RRBI product is not used correctly. Specificly, check to see if adhesive tape or record labels are being placed onto the RRBI before incubation. Also, confirm that staff are not writing on the vial with a Sharpie or other marking device. The autoreader is designed to pick up flourescent residue from spore growth; however, adhesive from tape or labels, along with inks can interfere and also signal as a positive. You will find this information explained under CAUTION in the 3M Auto-reader Operator's Manual.

For these reasons, AAMI standard ST46 recommends periodic grow out of RRBIs (at least weekly, preferably each day) to confirm via visible spore growth, that the early flourescent readout from the Auto-reader is accurate. AAMI also recommends gram staining positive BIs to verify spore growth (this requires continued incubation in the auto-reader or another 60C incubator). No visible color change in the vial (purple to yellow) or gram positive spore bearing rods identified via gram staining in the Lab, verifies a "false positive" which should be reported to 3M for corrective action via the FDA's Quality Systems Regulations). Expect a formal written response from 3M after a full investigation into your complaint, with a copy placed in their corporate Master Device file for FDA review during their next facility audit.

Chuck Hughes
General Manager/Educator
SPSmedical Supply Corp.
1-800-722-1529 www.spsmedical.com

[wbenitez]

3M has been working very close with us in attemps to determine the root cause of the problem. So far we have not experienced any more positives after the 3 hour monitoring in about a month. We are keeping our fingers crossed at this time. We will still continue to research the problem until it is resolved.

Thanks.

[boxmk]

Good Afternoon Willie! In the past when I have had "false" positives on the
3M Rapid Readout it was due to a couple of things:

1. Which someone else already mentioned....a vacuum leak which the bowie dick did not detect.
2. Operator Error! The technician had placed a load label on the vial and it did not allow the incubator to perfor an accurate reading.

Hope this helps!

[debbie]

If you are useing the newer version of the 3M incubator that sounds an alarm when there is a positive check (or have the 3M rep check) to make sure that the machine is not set to check the flash BI (blue cap) There is a control for that and it may be set wrong.

Just a thought

[ksuemc]

My facility has had X 6 +'s within the last month. I talked with vendor and sent in my incubator's for service. One has yet to be returned. I have had the service tech come and check all of my machines, too!