Other causes of failed PEth test for alcohol abuse?

"In conclusion, new tests for monitoring alcohol or drug use, such as the blood PEth test, can be useful even though a low positive test (<112ng/ml) by itself may not be proof of relapse. It is unlikely that the specificity of the blood PEth test will be 100%. There are essentially no tests that are perfect. Until adequate studies are performed to document more accurately the specificity of the blood PEth test it seems reasonable that a low positive blood PEth level should not be used by itself as proof of intentional alcoholic beverage consumption."

In 2003 Skipper claimed that a urine EtG > 100 ng/ml was proof of intentional alcoholic beverage consumption. From 2006 to 2012 the cutoff level proving drinking was raised from 250 then to 500 and then to 1000 ng/ml as the number of people getting positive tests who did not in fact drink continued to rise. As it was becoming more and more clear there was no cutoff level proving drinking Skipper claimed that proof of intentional alcoholic beverage consumption could be proved by testing for EtS. And when EtS was found to have the same problems as EtG the blood test phosphatidylethanol (PEth) was recommended as a confirmatory. In 2013 Skipper et al. claimed that a positive PEth test (> 20 ng/ml) could only be caused by heavy drinking and for the past 7-years it has been promoted and marketed as a highly specific test that reliable differentiates between incidental/extraneous exposure and drinking. In state physician health programs the consequences of a positive PEth test are fairly straightforward. At minimum, a positive test will require a 5-day evaluation at an out-of-state cash-only "approved" assessment center costing an average of 5K. These assessment centers typically recommend treatment lasting from 1-3 months and costing another 25-80K out-of-pocket and when discharged from treatment the PHP typically recommends a new monitoring contract for 5-years starting from scratch. It is at this point many of these doctors simply say "f*%k it" and kill themselves. In fact getting a positive PEth test near the end of a 5-year monitoring contract seems to be a common pattern -it occurs so frequently that it appears to be by design and when you consider the profit motive, opportunism and greed here it is highly probable.

The EtG, EtS and PEth were introduced as forensic tests with zero evidence base. All 3-were introduced and promoted as reliable, accurate and valid tests with high sensitivity and specificity and all 3 were subsequently found to be unreliable, inaccurate and invalid tests with very high sensitivity but poor specificity. These should never have been put out on the market and they now need to be removed. It is time to call bulls#*t on this charade.

Skipper GE, Thon N, Dupont RL, Baxter L, Wurst FM (2013) Phosphatidylethanol: The potential role in further evaluating low positive urinary ethyl glucuronide and ethyl sulfate results. Alcohol Clin Exp Res 37: 1582-1586.

I completely agree....the problem is that these “experts” are the the classic bad medical intern....they have no insight into their own ignorance. The classic “they don’t know what they don’t know.”

In skippers case, he seems to realize this and is at least helping now. Too late? depends on your point of view.

I have found a lab that is interested in helping me with a study to at least validate one cause of false positives in DBS PETH. It’s a start...

The pattern of getting a false positive near the end of a five year contract seems to be inevitable math... all the evidence one really needs is sitting there in plain sight.

I’ve found that these boards all want a “viable explanation” which is usually some form of incidental exposure that is unique to the individual. Not much interested in an explanation that applies to everyone.

So knowing EXACTLY what is happening is critical, so it can be uniquely associated.

That depends on what you mean by Skipper "seems to realize this and is at least helping now"? Are you referring to his availability as a paid expert witness or something more? Is this change in perspective presented as genuine mea culpa resulting from a sincere epiphany or is was it written as click bait for his medico-legal services. The specificity of any drug or alcohol test being used for forensic purposes needs to be as close to zero as possible to prevent false-positive tests. False positive tests should be non-existent to very rare. This requires extensive,and detailed research looking at multiple variables including metabolic and genetic differences, validity, cross-reactivity, cutoff levels, etc. etc. These issues need to be known well BEFORE the test is actually used for forensic purposes. The only research done on the EtG when it was introduced in 2003 and the PEth when it was introduced in 2013 was the research concerned with detecting and quantifying and the specificity of these tests is being determined post-market by trial and error. These consequences were predictable and avoidable.

I agree completely... shouldn’t have ever gone down like it did.

For what it’s worth it comes across as a genuine epiphany. He charges less than 20% the going rate, had a complete report to me in about 2 or 3 weeks (other expert reports less well written and researched took over 6 months and continuous nagging), follows up, returns calls, and is exceedingly professional and thorough.

I’ve been in both sides of an issue before. The perspective gained from that is unique. So I don’t consider it a deal breaker.

The opinion I offer here is from first hand experience.

Hey toolsd can you PM your phone # again. I have some info to give you

Hi, here is a follow up. My institution has allowed me to take 2 more Peth tests. One at my local Doc in a box and one at the actual rehab lab. Using the blood spot board, the lab worker at the rehab did the finger stick and then held my finger over the blood spot board. She said that the finger should never touch the board. The 2 times I have had the test done at the Doc in a box the tech smashed my finger on the 5 spots. One of those Doc in a box tests was positive. I know this seems very technical and picky but if this test is so sensitive that even touching the board can cause False Positives then it should not be used. There are to many unknowns about even how the test should be run. My $.02

I will tell you from watching my wife fail the finger prick tests I got real interested in exactly how it was collected. The USDTL test procedure sheet is very specific they are to prick finger and let the blood drop on the card. Not squeeze/milkIng and not touch the card.

We started making them do that and tests started passing. We also made them open a fresh kit in front of us. As you say no real proof but interesting you are seeing similar things.

There are some papers that talk about how milking screws up other tests. Not specific to the PeTH. The paper is published out of Rice university in Houston. I sent toolsd the paper. Don’t have it handy tonight.

Doc Langan, in addition to being a Doc, has studied this stuff for like ten plus years.

We had a discussion yesterday about the kinds of things necessary to get FDA approval. There seems little to no doubt the reason it isn’t FDA approved is that it’s so patently obvious it’s not worth the time and money, it won’t make the grade.

The guys who brought this to market *should* know this. That’s why it’s very existence and use is unethical. Us as, well, victims, expect a reasonable standard of care... we don’t know better and rely on these people.

It’s like we’re living in a third world country.

To my knowledge, the reason the FDA will not evaluate PEth (or for that matter, EtG/ETS) is that the tests were developed exclusively for profit. They have no therapeutic application.