Is Pyrogen testing done on non sterile units?

One of our customers have a requirement to perform Pyrogen Testing of the medical device units prior to sterilization.

I thought that pyrogen testing is done on sterile units and not non sterile units. Am I right ?

You are right.
Ask your customer why he wants to do it prior to sterilization ?
It is not that it cannot be done. Have at look into the attachment.

Thanks for the document.

The customer's justification is that they did 25 batches both pre- and post sterilization and found no differences. They also supported with ANSI-AAMI ST72:2002, Bacterial Endotoxins-Test methodologies, Reference section 6.6 which supports pre-sterilization samples to be tested.

I am not sure if by testing 25 or 50 batches and the results come negative, could we hold this as a justification ?

Is anyone in a similar situation ?

Pyrogenicity could be caused by the presence of hard-to-kill organisms/spores, or by residuals, or by general sterilization failure. With regard to the first of those, pyronema domesticum is endemic on cotton from some parts of east Asia and from some other growing areas, and is more difficult to kill (with EO) than bacillus atropheous, the normal EO biological-indicator organism,so that normal EO sterilization qualification does not establish either sterility or inherent non-pyrogenicity if pyronema is present on the pre-sterilization cotton.

The point of pre-sterilization testing of cotton containing devices, I would think, would be to avoid the expense of EO processing if viable pyronema is present.

Great points, MIREGMGR. The product in question are Intravenous tubing sets.

I had the same concern which you expressed but not sure how to convince the customer for their pre-sterilization approach on pyrogen testing.

Hi Guys,

Do you know what actions could you take if the pyrogen test failed?

Is there the possibility of cleaning or wiping down the failed lot and send for re-test?

We are going to start performing pyrogen test to our product and would like to know if cleaning or wiping the lot if it should failed the test is an option.

Thanks in advanced for the feedback.

csterling said:

Do you know what actions could you take if the pyrogen test failed?

Is there the possibility of cleaning or wiping down the failed lot and send for re-test?

Click to expand...

You need to technically understand the source of the pyrogenicity... one of the three possible causes mentioned in the post above (presence of hard-to-kill organisms/spores such as pyronema, or excessive EO residuals, or general sterilization failure), or a chemical characteristic of the patient contact material (toxicity, etc.) that causes it to be non-biocompatible. The latter should show up in proper biocompatibility qualification-testing of materials prior to design, thus in theory it shouldn't be the cause of a surprise post-production failure, but it needs to be on the possible-causes list.

None of these causes can be fixed by "cleaning or wiping down".

csterling said:

Hi Guys,

Do you know what actions could you take if the pyrogen test failed?

Is there the possibility of cleaning or wiping down the failed lot and send for re-test?

We are going to start performing pyrogen test to our product and would like to know if cleaning or wiping the lot if it should failed the test is an option.

Thanks in advanced for the feedback.

Click to expand...

The action to be taken is to detect the source that could get the pyrogen to levels which fails your test.
Pyrogen is the outer layer of dead gram negative bacteria.
The source of this is mostly water, but not always
Prevent this and you will be good ...

Pyrogen is the outer layer of dead gram negative bacteria.

Click to expand...

Maybe basic question.

Does it means that sterilization kills gram negative bacteria, but not remove pyrogen?
The outer layer of dead gram negative will be remaining although the bacteria itself will be killed.
So pyrogenicity is not removed by sterilization if gram negative bacteria is on pre-sterilization device.

Is this understanding correct?

Soog1459 said:

Maybe basic question.

Does it means that sterilization kills gram negative bacteria, but not remove pyrogen?
The outer layer of dead gram negative will be remaining although the bacteria itself will be killed.
So pyrogenicity is not removed by sterilization if gram negative bacteria is on pre-sterilization device.

Is this understanding correct?

Click to expand...

Yes.
Yes..
Yes...

Read this also ... http://www.atlasbio.com/faq/endotoxin-and-standards [dead link as of 11.2016]