Nigel's TMAU machine |
will start adding this paragraph to their TMAU urine test results they send out ...
We have added the following comment onto all of our reports:
'Please note: not all causes of malodour have been ruled out by this test. Malodour can be caused by other volatiles such as hydrogen sulfide, methanethiol, cysteamine and dimethyl sulfide. Unfortunately, we are unable to test for these volatiles at present.'
Hopefully this will help with the education of the medical community
Why are they doing that ?
We don't know (yet), but we can speculate.
Background to SHEFFIELD CHILDREN'S HOSPITAL TMAU test program :
The Sheffield test was started by NIGEL MANNING around 1997.
This was at his own volition. The system or politicians did not ask him.
If it wasn't for Nigel, there would be no UK TMAU test program.
Nigel's test was known for being the only lab that seemed to give a TMAU2 (TMA overgrowth) diagnosis, and for giving the most TMAU1 (genetic TMAU) positives (around 33%) even though his TMAU1 reference range 'cut-off point' was set probably too high (i.e. too hard to get a positive result).
Nigel retired around 2016.
Around 2017 the machine broke, and a new method was used for TMAU urine testing by the new operator.
This new method is similar to other TMAU lab testers (e.g. USA Denver).
There are now no known TMAU2 positives (same as Denver) and TMAU1 positives are now around 18%.
Until this new information, it seemed SCH was not a lab (since Nigel left) that wants input or influence from the community.
Nigel helped individuals greatly, but his community help was limited. They didn't really help TMAU any further (e.g. awareness).
Usually these labs seem to be very conservative, and a consensus is usually reached on a test method and ref range by consensus of many labs. But so few labs test for TMAU that there's very little innovation, and most are now using the same method.
Speculation on why SCH are adding this new paragraph :
1. Perhaps so many 'normals' are contacting them to say they find it hard to believe they are normal, or perhaps they used to fail the test in Nigel's days, and now they pass.
2. The 'streetname' for the disorder is 'fecal body odor, yet TMA smells of fish. So even though TMA should be an excellent FMO3 biomarker, you have to guess that the likes of dimethylsulfide and methanethiol are stronger candidates for causing the smells (amongst many other sulfides).
3. Dr Ron Wevers published a paper recently about another enzyme fault that causes metabolic halitosis resulting in smelling of those 3 sulfides. This is probably the main reason.
4. Maybe the new test operator is getting more interested in the subject now.
Sheffield isn't a very helpful test lab. They do what they have to, and probably give good personal replies, but overall could do much more.
UCL in London (Dr Lachmann's base) offered to take over the test program, which probably would be better for the community (slightly), but it seems Sheffield want to keep the test. Presumably UCL think there's not room for 2 UK TMAU test labs.
Dr Lachmann is in a top-level NHS commitee (as the 'metabolic diosrder' expert rep), so could be very influential.
The UK NHS metabolic test labs also have a commitee, which SCH are part of (naturally). This is perhaps a bit less influential than Dr Lachmann.
Dr Ron Wevers lab, the Netherlands TMAU test lab
Dr Wevers seems to no longer use the TMAU urine test, deeming it too unreliable (i.e. can't rely on the positive/negative results.)
It seems he uses the DNA test first (so testing for TMAU1 cases).
Moving Metabolic Malodor beyond TMAU
Currently the only documented Metabolic Malodor disorder is TMAU.
But with people saying they smell of feces/gas etc, it seems like they will smell of many sulfide volatiles, and TMA might not even be part of the malodor.
So it's very good news that they put that extra paragraph in to at least show acceptance that people might smell of volatiles other than TMA.
What can we do ?
For Sheffield we could email them to ask them to test for more volatiles (ones that are stronger suspects).
We could write politicians to ask them to write Sheffield about this.
We could ask anyone with influence on the lab (such as higher up the NHS command chain ... even to the top).
Of course you can do this sort of campaign for labs in other countries too (politicians are a good bet).
Overall, it is at least a positive step by SCH. It's good they are at least making Drs aware there could be other volatiles to blame, but the way the system works it needs 'researchers' to take up the research on their own volition. That seems to be the way health research works in most countries (pretty ridiculous).
There should be a 'body and breath malodor' research center and clinic, but that's not the way the systems work. Instead we have to hope individual researchers will start a study (very unlikely currently).
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