CDT Test (Carbohydrate Deficient Transferrin)

Convicted Driver Insurance

topchippyles

Well-known member
I personally think you could have problems in a couple of ways, if you're Stella is 440ml and you're having 18 cans over a weekend that's 37.8 units alone excluding owt else you're not having. If you're asking about testing for cannabis presume you're smoking it, at your medical they ask when you last had more than 6 units in one session and they'll ask you how often you have more than 6 units in a session so if you're honest at medical a weekend is Friday, Sat and Sun 37.8 units divided by 3 days is 12.6 units so in 1 day out of your weekend you're drinking pretty close to the weekly recommendation but you're doing it 3 times a week, yet you're saying you don't have a problem with drink.......in eyes of DVLA and Govt recommendations you're binge drinking 156 days out of 365!!!!

Sorry to be blunt......am from Yorkshire!!!!
Straight is the only way to be but kind with it as you always are jimbob
 
I personally think you could have problems in a couple of ways, if you're Stella is 440ml and you're having 18 cans over a weekend that's 37.8 units alone excluding owt else you're not having. If you're asking about testing for cannabis presume you're smoking it, at your medical they ask when you last had more than 6 units in one session and they'll ask you how often you have more than 6 units in a session so if you're honest at medical a weekend is Friday, Sat and Sun 37.8 units divided by 3 days is 12.6 units so in 1 day out of your weekend you're drinking pretty close to the weekly recommendation but you're doing it 3 times a week, yet you're saying you don't have a problem with drink.......in eyes of DVLA and Govt recommendations you're binge drinking 156 days out of 365!!!!

Sorry to be blunt......am from Yorkshire!!!!

Yes I possibly did go over the top last year but I’m not being funny most people turned to alcohol due to the lockdown and i was one of them but I’m finding it easy not to have a drink, so surely this means I don’t have a problem. Thanks for the maths I wasn’t asking about that as I know and already done my drink drive course.
 
Hi, nobody can be certain if you will pass but you should be ok, if you keep of the sauce until after the test. the longer the better as they say

unless your booked in for a urine test they are unlikely to test for drugs as the alcohol test is blood.

if you trawl the web you can get a copy of the questionnaire - google HRO medical questionnaire

Being a HRO, bear in mind the weekly uk guideline is 14 units a week and you cant go above that and not in one sitting

They will contact your GP to investigate your medical history, so make sure you get a copy of your records and see if anything is mentioned regard alcohol.
If youve mentioned you drink more than 14 units a week to your GP (as they always ask casually how many units you drink , how many fags you smoke - its bad for you routine) they .will have noted this on your medical record and the DVLA may then class you as ok or as an alcohol misuser, and for that you have to evidence controled drinking for 6 months, 12 month abstinence if classed as dependant and prove it!

Hi,

thank you so much for your response! Do you think I should move it possibly to the end offeb just to be safe?? No urine test just blood! :) you’ve made me a feel a lot more calm!
I’ve never been to the doctor about alcohol so I’m hoping that will come back ok! Thank you so so much x
 

rufus

Well-known member
Hi,

thank you so much for your response! Do you think I should move it possibly to the end offeb just to be safe?? No urine test just blood! :) you’ve made me a feel a lot more calm!
I’ve never been to the doctor about alcohol so I’m hoping that will come back ok! Thank you so so much x
If your worried, delay the test a little longer, the longer you abstain the lower your cdt result will be.
If you want to make sure your ok, get a private CDT test in the mean time, but its not cheap

Have the dvla sent you a questionnaire to fill in - the dvla gp will also have a form to fill in , obviously your answers to both will need to tally.
To be safe I would also lay off the weed , that would give you a month to get clear should they test for drugs.

I dont want to preach to you but I feel you need to address your drinking before it takes control of you - Ive been there and got the t shirt - lost my job, lost my house, lost my mind, I dont wish others to fall into the same trap as I did.

Stay safe and in the long term try to reduce them units - swap to something a weaker than "wife beater", every little bit helps
 

Jimbob

Well-known member
Yes I possibly did go over the top last year but I’m not being funny most people turned to alcohol due to the lockdown and i was one of them but I’m finding it easy not to have a drink, so surely this means I don’t have a problem. Thanks for the maths I wasn’t asking about that as I know and already done my drink drive course.
Ok well re original post, no one can say if you will pass medical it depends on a lot of stuff, if you answer the questions honestly stating that in the last year you binge 3 days a week and what your alcohol take is on average a week oh and that you also smoke cannabis then I think you could have issues, glad you found the DD course productive like many of us! Oh and an additional bit of info, on my DD course my instructor a lovely bloke called Santokh told our group our advised our group of 6-8 weeks of no booze prior to medical.
 
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rufus

Well-known member
Yes I possibly did go over the top last year but I’m not being funny most people turned to alcohol due to the lockdown and i was one of them but I’m finding it easy not to have a drink, so surely this means I don’t have a problem. Thanks for the maths I wasn’t asking about that as I know and already done my drink drive course.
I think what Jim was pointing out it is how the DVLA look at it - you dont have to drink everyday to have a bad relationship with alcohol or be classed as dependant - to be classed as a misuser, takes very very little, remember 3 cans of stella is classed as binge drinking and we know everybody drinks more than 3 when they go out but being a HRO you cant.
The gov guidelines for binge drinking and units in a week are only guideline until like us you are charged with DD
Being a HRO they then become the max limits you are allowed (if you want your licence back) - if you go over them, the DVLA then class you as misusing alcohol or dependant and then the fun begins.
 
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Mr Blue

Member
I know it’s so daft but when I found out I googled and this came up ....
Carbohydrate-deficient transferrin, known as “%CDT,” is a blood test to detect heavy alcohol use (five or more drinks a day) over the past two weeks. 1 This alcoholbiomarker can provide clinicians with an objective way to screen and monitor clients in treatment for alcohol use disorders.
When I read this I never thought any more of it as I don’t drink every day five or more drinks. Obviously it’s getting nearer to the medical and I am getting anxious so thought I would look more into it stupidly far too late and came across this forum.
your right I do value my licence don’t we all but I suppose non of us would have been in this position in the first place. I shall take your advice and re arrange the appointment thanks ever so much for your advice I shall not be drinking for a while until my medical is complete.
thanks again ?
How did you get on?
 

IY50

Member
Good Morning,

I'm in need of some good advice.

I was refused my licence renewal back in Sept 2020 as I registered 3.0 on my CTD levels. I was very nieve regarding the medical and blood test and consumed alcohol a few days before the test. I obviously had to wait another 6 months to reapply for my licence.

Because of this I decided to change my lifestyle completely. I've been abstinent for over 6 months, bar two occasions, Christmas Day (glass of wine) and New Years Eve (2 whiskies).

My bloods were taken on the 19th March 2021. I called the DVLA on the 30th March and they said they had received all the relevant documentation and was scanned on their system awaiting review.

Obviously, as many of you have experienced, Covid and the industrial action by members of the DVLA has prolonged the waiting times enormously. I decided after 6 weeks of weekly calls to contact Tim Burton to try and get some information. He replied below:

Dear Mr Young,

I would like to apologise for the difficulty that you have had in trying to contact DVLA.

I asked one of my Doctors to review your application. The outcome of that review is that your application has been refused. The summary of the medical review is that your previous application was refused in September 2020 because of a high reported CDT level. Your recent CDT is again high and is not consistent with controlled drinking, nor with your declared alcohol intake.

I understand that this decision will come as a disappointment to you. However, we have to make licensing decisions based upon the medical evidence presented to us. In the case of an HRO this includes CDT levels.

Yours sincerely,

Tim.


As you can imagine, I'm absolutely devastated!.. I replied to him asking how this could be, and he just stated that I will receive the refusal letter containing the reason for their decision. I've got a call with my doctor this afternoon to discuss this situation.

Has anyone had experience of this?.. What should I be asking my doctor?

Thanks.
 

price1367

TTC Group
You need to ask your doctor if he can do a blood test to check for anything that could cause a high CDT reading. My knowledge only extends to a few very significant liver disorders that can cause this, but they are extreme enough that I would have expected you to have very noticeable symptoms.
You need to find out what the CDT result was. Has it come down at all ? Because you failed the last one I expect them to be looking at a score of under 1% which is lower than they would want from ordinary applications.
 

IY50

Member
Afternoon John,

Received my refusal letter yesterday. My CDT level was 2.4%. That’s no alcohol since 20th Sept 2020 until my blood test 19th March 2021. Still continuing not to drink. Completely baffled?

I’ve discussed the situation with my GP and I’m going in for various blood tests this coming Wednesday. My only hope is that I can prove to the DVLA that the high CDT reading is not alcohol related?

As it stands, I could accept the decision, go another 6 months and reapply, with the same possible CDT reading. No further forward, waste of time/money and not getting to the root cause.

This situation must have happened to others, I can’t be the first?

Thanks, Ian.
 

topchippyles

Well-known member
Afternoon John,

Received my refusal letter yesterday. My CDT level was 2.4%. That’s no alcohol since 20th Sept 2020 until my blood test 19th March 2021. Still continuing not to drink. Completely baffled?

I’ve discussed the situation with my GP and I’m going in for various blood tests this coming Wednesday. My only hope is that I can prove to the DVLA that the high CDT reading is not alcohol related?

As it stands, I could accept the decision, go another 6 months and reapply, with the same possible CDT reading. No further forward, waste of time/money and not getting to the root cause.

This situation must have happened to others, I can’t be the first?

Thanks, Ian.
There are other causes that can effect cdt levels but i am no expert. Cannot recall seeing other related posts but sure there must be some who have had high readings and alcohol free.
 

price1367

TTC Group
Here is an explanation for raised CDT from causes other than alcohol:

2) All possible/probable explanations for the increase in the CDT level to include whether any other factors inflate CDT levels.
Alcohol misuse is the commonest reason for increases in CDT levels. In most studies of CDT in subjects potentially misusing alcohol the test has 95% specificity i.e. 19 out of 20 times the increased CDT is due to excess alcohol intake. There are a number of other causes of a raised CDT as detailed below:
a) Advanced cholestatic liver disease: In patients whose bile ducts are obstructed or damaged by disease e.g. primary biliary cirrhosis, primary sclerosing cholangitis, gallstones or liver/pancreatic cancer, removal of CDT from the blood is reduced leading to raised CDT levels. This can be excluded in the case in question by the normal biochemical liver tests as the disease needs to be severe for there to be an effect on CDT.

b) Transferrin variants: The normal form of transferrin in blood is the C-type. Two more variants exist: the B- and D- types. The B-type is extremely rare. and is of no relevance in this case as it causes falsely low CDT results. The D type is very rare in Caucasians, with a prevalence of less than one in 10,000, but has been shown to cause falsely raised CDT levels. It is more common in Africans, in whom studies have shown a prevalence of CD heterozygotes of up to 10%.

c) Carbohydrate deficient glycoprotein syndromes: A group of very rare syndromes has now been identified in which an inherited deficiency of the enzymes that add the sidechains to proteins occurs. To date only around 200 cases have been described in the literature. In an affected child there is severe mental retardation together with other physical abnormalities and CDT levels are in the range 50-100%. In heterozygous, or carriers of the disease, CDT levels are variable but typically are in the range 10-25%.


I hope it isn’t a( but if it was you would be suffering from symptoms that would be noticeable.
c( would not apply as your level is too low, which leaves b(....... it could be worth asking about which variant is causing the higher levels.
If you get the all clear from tests with your GP then I suggest you take up the problem with DVLA, say there is no apparent cause and you would like a further test with the CDT result being split into its component parts rather than just an overall score.
 

IY50

Member
Afternoon John,

I thought I'd update you as follows.

Appointment with my GP last Thursday, explained the situation and he was very helpful. Like a number of people in this situation, GP don't know a lot about CDT tests as not used in normal GP practice.

He took bloods and sent off for the following tests:
• Liver function (LFT)
• Gamma-Glutamyl Transferase (GGT)
• Mean Corpuscular Volume (MCV)
• Alanine Transaminase (ALT)
• Aspartate Aminotransferase (AST)
• I'm also waiting for an appointment for a NASH Test - Ultrasound scan of liver for fatty deposits not related to alcohol - This could take a few weeks to come through.

He also gave me a copy of the Doctors Medical Questionnaire that was submitted as part of my licence application. All questions answered in support of my application - No issues with alcohol.

The results came back early afternoon Friday - All fine - No Further Action Needed. He left a copy of the results for me to collect from reception. I'm not medically trained, so I need to research what each figure signifies in relation to my case?

I have yet to contact him regarding how to use the above results (and the eventual NASH test) to challenge the DVLA's decision.

I did mention EtG / FAEE & PEth tests to prove previous abstinence at my appointment, but he was unaware of these tests and didn't know how to refer me for these. So I guess this is where the DVLA could ignore these results as they are not through my GP. These are used by CAFCASS in child custody cases and I have quotes from 2 Labs. They're quite costly - £800. So I need to be sure they'll be regarded?

Any advice/info gladly received.

Many thanks,

Ian.
 

price1367

TTC Group
Afternoon John,

I thought I'd update you as follows.

Appointment with my GP last Thursday, explained the situation and he was very helpful. Like a number of people in this situation, GP don't know a lot about CDT tests as not used in normal GP practice.

He took bloods and sent off for the following tests:
• Liver function (LFT)
• Gamma-Glutamyl Transferase (GGT)
• Mean Corpuscular Volume (MCV)
• Alanine Transaminase (ALT)
• Aspartate Aminotransferase (AST)
• I'm also waiting for an appointment for a NASH Test - Ultrasound scan of liver for fatty deposits not related to alcohol - This could take a few weeks to come through.

He also gave me a copy of the Doctors Medical Questionnaire that was submitted as part of my licence application. All questions answered in support of my application - No issues with alcohol.

The results came back early afternoon Friday - All fine - No Further Action Needed. He left a copy of the results for me to collect from reception. I'm not medically trained, so I need to research what each figure signifies in relation to my case?

I have yet to contact him regarding how to use the above results (and the eventual NASH test) to challenge the DVLA's decision.

I did mention EtG / FAEE & PEth tests to prove previous abstinence at my appointment, but he was unaware of these tests and didn't know how to refer me for these. So I guess this is where the DVLA could ignore these results as they are not through my GP. These are used by CAFCASS in child custody cases and I have quotes from 2 Labs. They're quite costly - £800. So I need to be sure they'll be regarded?

Any advice/info gladly received.

Many thanks,

Ian.

No do not spend money like that as it will not be of any use in a DVLA application. They rely on CDT themselves, and will accept LFT results done through, and reported by, your GP.
Any independent tests poses the problem of ‘who supplied the actual sample?’ And DVLA will not consider the results, so save your money!
 

topchippyles

Well-known member
No do not spend money like that as it will not be of any use in a DVLA application. They rely on CDT themselves, and will accept LFT results done through, and reported by, your GP.
Any independent tests poses the problem of ‘who supplied the actual sample?’ And DVLA will not consider the results, so save your money!
I spoke to my surgery today and they send a letter back to the dvla on the 18/5/2021 so i am hoping to get a letter to book a medical soon. Question are these the current traffic light system used by the dvla john. I saved it off a thread a while back so not sure if its up to date as i have booked a private CDT test for piece of mind.


A %CDT result below 1.7 suggests no recent excess alcohol intake.

A %CDT level result between 1.7 and 2.2 suggests recent excess alcohol intake.

A %CDT level result between 2.3 and 2.9 indicates regular
heavy amounts of alcohol consumption and can be an indication of increasing risk or higher risk drinking.

A %CDT result of 3 or more indicates regular excess amounts of alcohol consumption and can indicate alcohol dependence.

The above is so called the traffic light system, if they allow you to drive or not or if they ask questions to your doctor for more information. I put NO to everything on the questionaire.

Now here's the rub for you all, on the actual medical test by SYNLAB it states this, i think this is VERY important for all on here:

Classic CDT (%)
DVLA Green <1.3
DVLA Amber 1.3 - 1.6
DVLA Red >1.7
 

price1367

TTC Group
I spoke to my surgery today and they send a letter back to the dvla on the 18/5/2021 so i am hoping to get a letter to book a medical soon. Question are these the current traffic light system used by the dvla john. I saved it off a thread a while back so not sure if its up to date as i have booked a private CDT test for piece of mind.


A %CDT result below 1.7 suggests no recent excess alcohol intake.

A %CDT level result between 1.7 and 2.2 suggests recent excess alcohol intake.

A %CDT level result between 2.3 and 2.9 indicates regular
heavy amounts of alcohol consumption and can be an indication of increasing risk or higher risk drinking.

A %CDT result of 3 or more indicates regular excess amounts of alcohol consumption and can indicate alcohol dependence.

The above is so called the traffic light system, if they allow you to drive or not or if they ask questions to your doctor for more information. I put NO to everything on the questionaire.

Now here's the rub for you all, on the actual medical test by SYNLAB it states this, i think this is VERY important for all on here:

Classic CDT (%)
DVLA Green <1.3
DVLA Amber 1.3 - 1.6
DVLA Red >1.7

A simple question, but a hard answer!

I would say that the Synlab one is the closest to the DVLA position, UNLESS they are looking at someone who has been classified as alcohol misuse or alcohol dependent when they will be looking for a lower score than that scale. Certainly for alcohol dependence they seem to want a reading in CDT of below 1%
 

IY50

Member
No do not spend money like that as it will not be of any use in a DVLA application. They rely on CDT themselves, and will accept LFT results done through, and reported by, your GP.
Any independent tests poses the problem of ‘who supplied the actual sample?’ And DVLA will not consider the results, so save your money!
Afternoon John,

Just an update regarding the various tests I’ve had. As I mentioned previously, all of my blood work came back as normal. I’ve had the liver ultrasound scan and received the results last week, all normal.

The doctor has kindly provided a covering letter including all of the test results and my 8 months abstinence, requesting these be taken in to consideration when assessing my fitness to drive on appeal.

Do you have any advice as to how to word my appeal letter. As my CDT levels were 2.4 after 6 months abstinence, I assume the best I could hope for is another DVLA medical and blood test which, fingers crossed, would read below 1.0?

My fear is after all of these tests reading ‘normal’ and a further CDT test comes back high, where do I go medically to prove these readings are not alcohol related?

Your advice would be greatly appreciate.

Thanks, Ian.
 

price1367

TTC Group
Ian,

Generally DVLA would not entertain a further CDT test until 6 months have elapsed.
There are 2 ways of appealing a decision, you can go to the Magistrates court for a formal appeal, but it seems that these always fail, or you can do a written appeal to dvla.


If you appeal in writing to DVLA you should detail what tests have been done by your GP and how long you have been abstinent.
You can try asking them to perform another CDT test but that this should be more detailed to break down the CDT into it’s ‘finer’ points. There can be (rare) instances where a general CDT result can be elevated, point out the below report:


I am wondering if it would help your case if you made a Statutory Declaration of the fact that you have not consumed alcohol since XX date, and that you know of no reason why your CDT score should be elevated.
Whilst this is not legally binding, it is more formal than just saying in a letter that you have not been drinking…..
You can complete one in the link below, print it out and have it formally witnessed before you send it with your appeal letter.

 

IY50

Member
Ian,

Generally DVLA would not entertain a further CDT test until 6 months have elapsed.
There are 2 ways of appealing a decision, you can go to the Magistrates court for a formal appeal, but it seems that these always fail, or you can do a written appeal to dvla.


If you appeal in writing to DVLA you should detail what tests have been done by your GP and how long you have been abstinent.
You can try asking them to perform another CDT test but that this should be more detailed to break down the CDT into it’s ‘finer’ points. There can be (rare) instances where a general CDT result can be elevated, point out the below report:


I am wondering if it would help your case if you made a Statutory Declaration of the fact that you have not consumed alcohol since XX date, and that you know of no reason why your CDT score should be elevated.
Whilst this is not legally binding, it is more formal than just saying in a letter that you have not been drinking…..
You can complete one in the link below, print it out and have it formally witnessed before you send it with your appeal letter.

Many thanks John.
 
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