Consecutive invalids

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Consecutive invalids

Post by mqavi421 » Fri Jun 28, 2019 7:33 am


I have a donor who has tested invalid with abnormal pH two consecutive times. First sample's pH was 9.2, second sample's pH was 9.0. There is no good medical reason. There doesn't seem to be a long delay with collection and sample being received at the lab.

I forgot to mention that second specimen was a directly observed collection

How would you proceed?

Thanks for the help!

Robert Swotinsky MD
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Re: Consecutive invalids

Post by Robert Swotinsky MD » Tue Jul 02, 2019 5:57 am

If the second specimen is invalid for the same reason as the first specimen, the MRO reports test cancelled. No further action is required unless a negative result is required, i.e., pre-employment, return-to-duty, or follow-up. If a negative result is required, the employer sends the donor for a clinical assessment to determine if the donor is misusing drugs.


Re: Consecutive invalids

Post by mikesuls » Fri Aug 16, 2019 10:37 pm

I would call the collection site and make absolutely certain that the second collection was truly done under direct observation. The way I do it is very simple: "Please describe exactly how you performed a directly observed collection". If they deviate from the regulations as outlined in subpart 40, I will send them for a third collection, preferably with a different observer. If the collector correctly describes the observation procedure, then, I agree, the test is cancelled. No further action unless a negative result is required.

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