Tag Archives: testing

The Holy Grail

I have had a big day.  BIG.  Huge.  If you’ve never seen the film ‘Pretty Woman’ you won’t get the reference, but trust me when I say today may have been a game changer.

The Holy Grail for anyone suffering from Histamine intolerance (HIT), and people with Mast Cell Disease who find it necessary to follow a low histamine diet, is the ability to test the food we eat for histamine.  The reason it’s so vital is that many factors affect histamine formation, the main ones being how old a food is and how it’s been stored.   A lab testing the histamine content of imported strawberries that have spent weeks travelling from Israel, for example, may come up with a very different result than if they’d tested strawberries taken straight off a bush in their garden.  And how do we know if a specific strain of British strawberries have the same histamine content as a specific strain of Spanish strawberries?  The answer is, we don’t.  Realistically the only way to test the amount of histamine in the food we eat is to actually test the food we eat, and my food here in the UK will be different to the food you might be eating in the States, Europe, Australia, Asia or anywhere else on the planet.

In October 2018 I wrote this post about researchers at City University of Hong Kong who were developing a way of testing for histamine using your mobile phone and a sensor.  Well, today I had the joy and privilege of meeting one of the researchers, Victor Lau, while he was on a short trip to the UK.  I have been excited all week waiting to meet Victor and was not disappointed.  He was absolutely lovely and has given me permission to talk about our meeting and the home histamine testing device.

Hong Kong practically lives on fish and seafood but food standards aren’t as good as they might be, so since 2016 the researchers have been working on a way to test for histamine in seafood for use in the commercial food industry.  The research is Government funded so not driven by profit.  Until I emailed them back in October they had never heard of Histamine Intolerance or Mast Cell Diseases and are now hugely interested in our plight.  Victor made a point of telling me that it’s not through any desire to make money out of us – they genuinely love the idea of helping patients and when the device becomes available to buy they will keep the cost as low as they possibly can.

I have to stress that the current device is a prototype and still being refined.   There’s a long way to go to reach a saleable product, not least because the results have to be rigorously accurate if you’re dealing with sick people and allergic reactions and then the device would need the relevant Governmental approval, however I’m assured that we’re only talking 3-4 months before a working prototype would be available for me to test 😮

The equipment needed for the current testing system is as follows:

  • An app for your phone.  They gave me the app and it was a doddle to install on my Android phone.
  • The testing device, which is about half the size of a mobile phone.
  • Some testing strips – these slot into the side of the testing device and you place your food sample on the strip.
  • Some food to test, preferably something which can be formed into a liquid when mixed with water.
  • Some distilled water.
  • Some weighing scales able to measure in individual grams.
  • A dropper.

Here’s a picture of today’s set-up:

This is how the testing currently works:

  • Place a sterile pot on the weighing scales.
  • Measure out 1gram of food into the pot.
  • Add the same amount of distilled water.
  • Mix together until you have a liquid thin enough to pass through a dropper.
  • Open the app on your phone – it gives you guided instructions as to how to conduct the test.
  • Using a dropper, place 2 drops of the food mixture onto the end of the testing strip (that’s the small orange-coloured strip sticking out of the right side of the device in the middle left of the picture).  Wait 2 minutes for this to be measured and registered.  Wipe off.
  • Add 2 drops of distilled water onto the testing strip to re-calibrate.
  • Repeat another 4 times, alternating food and water.
  • An average histamine content will be calculated from these 5 samples.
  • At least, I’m hoping I’ve got the technique correct – I’m no scientist and it was all new to me!  I’ll show the guys this post and they can correct me if I’ve got something wrong.

Victor about to weigh tea!

The process is a little time consuming, taking about 10 minutes per food item, but it’s really easy to do.  Currently it’s not something you’d be able to do in a restaurant, but I don’t care so long as I can test the food I eat at home!  Speaking of which, Victor asked me to take some food samples along to be tested.  They’d never tried the device on anything other than seafood, so were as excited to see the results as I was!  However, the device is currently only calibrated to test for histamine above 100ppm (parts per million), which is a safe level for healthy people but of course not for those of us who have to follow a low histamine diet – we need to be able to test for 20ppm at the very least and Roy Vellaisamy, Victor’s colleague in Hong Kong who I spoke to today on the phone, assures me this should be possible.  So bear in mind today we could only say if a food was below 100ppm or above 100ppm but not give a precise figure.

I miss tomatoes sooooooo much, so the first food tested was tinned, chopped tomatoes from Tesco.  They tested above 100ppm so there’s no way you could include them in a low histamine diet 😦  However, I’d also taken with me a fresh tomato and this tested below 100ppm!  We’ve no idea, though, how much below – it could be 10ppm or 99ppm so tomatoes are still not a food I’ll be eating until I know for sure how much histamine they contain.  Interestingly, Victor re-tested the fresh tomato a couple of hours after I left, which by this time had been out of the fridge and in a warm environment for several hours.  It now tested above 100ppm, which on the surface looks as if histamine had formed rapidly in the warm environment in which Victor was testing.  However, it may not be quite that cut and dried.  We only know it initially tested below 100ppm, but we don’t know by how much – it could actually have been 99ppm.  And in the second test, we only know it tested above 100ppm, but again we don’t know by how much – it could just be 101ppm.  Of course, on the other hand it could be that it tested as low as 30ppm on the initial test, but after being kept at room temperature for several hours it had reached histamine levels of 190ppm!  The ability to test precise levels of histamine in a food sample is something which would be vital to us if the device were to be useful to us as a patient population.

The next food I wanted to test was a good old British brew (well, actually, my tea was organic black Clipper tea from some far off land 😉 ).  I was gutted when this tested above 100ppm (and that’s without adding milk) but I have to be honest and say I still don’t think I can give my daily cuppa up.  Histamine is a bucket effect, and as long as my bucket is low from eating foods low in histamine the odd cup of tea shouldn’t fill the bucket too much and tip me over the edge and into a reaction.  That’s my excuse anyhow and I’m sticking to it 😉

By this time my train home was almost due, so I had to leave my other samples with Victor to test in my absence.  I’d taken some Quorn mince and some cocoa powder, so I’ll let you know the results when I have them.

Today has felt like a watershed day for those of us with HIT and/or MCAD.  I can’t stress enough how interested both Roy and Victor are in our situation, how generous and lovely they are being with me and how much they genuinely want to help.  It certainly makes a change from the usual way we rare disease patients are treated.  I told Victor that HIT seems to be much more recognized in Germany than here in the UK, and he luckily has a close colleague who lives in Germany whom he can find out more from.   For my part, I gave him Dr Seneviratne’s details being as though he’s the leading HIT & MCAD doctor in the UK and is so knowledgeable on all things histamine.

Victor stressed that they want to make a device which is useful to us, so if any of you have any questions please do comment below this post and I’ll forward them all.  I have every faith that, with a bit of tweaking, the device could be brilliant for us – the ability for you to be able to test the food you eat, and for me to be able to test the food I eat, would be awesome and something I didn’t even dream would be possible.  Not only that, but Victor thought it wouldn’t be too difficult to develop the device to test for things other than histamine – nuts, for example, or gluten!  All that would be needed is a separate testing strip whose receptors bind to gluten instead of histamine – the rest of the testing kit, ie the app and device, would remain the same.  Imagine the possibilities in our modern world where food allergies are rampant!

Watch this very exciting space 🙂





Home testing for histamine

Back in October I wrote in this post about some researchers from Hong Kong who were in the process of inventing a sensor which works with your mobile phone to test for histamine in foods.  There are a handful of other researchers around the world who are also working on ways to test for histamine in foods, but the Hong Kong group seemed to be the closest to development so I contacted them to find out more.

They had principally built the device for use in the food industry, so that supermarkets and food manufacturers could test their foods for spoilage, but when I told them about MCAS and HIT patients they were extremely interested in our plight – they didn’t know there was a patient population out there who were desperate for a way to test for histamine in foods and had never considered selling the device to the general public.

They were still working on a prototype but asked me if I’d like to test it and give them feedback.  Is the Pop Catholic?!  I said I’d love to, but by Christmas had heard nothing from them.  Last week I emailed the team again who replied straight away to apologise for not being in touch.  Apparently they had had some issues with the chip inside the sensor device, and one of the researchers was currently in Taiwan liaising with another company to produce the chip.  He did, however, send me a video of the device and asked for my comments.  I’m not sure how much I’m allowed to say as obviously there is the competition to think about, but the device looks straight forward enough to use if a little fiddly.  It isn’t the case of sticking a probe into a food item and taking a reading which is what I’d kind’ve had in mind, but once I’d got my head around the fact it will be more complex than that I still think it’s going to be usable by the public, at least in a home environment if not in restaurants or on the run.  They are hoping to streamline some parts of the process before it becomes generally available.

One of the researchers is coming over to London in February and asked for a meeting with me, but unfortunately he’ll be in London and I’m not sure I feel up to travelling 600 miles just to have a half hour meeting :-/  I was hoping one of my good friends who lives nearer the capital would be able to attend instead, but unfortunately she’s really unwell at the moment and doesn’t feel up to it.  It feels like a hugely wasted opportunity 😦

Obviously I’ll keep you all informed of developments.  Any chance to test for histamine in foods would be a massive bonus in mine, and many of your, lives.  The first thing I’d look at is tomatoes………….how I miss them……..closely followed by tea!


The Truth About Histamine in Foods

As regular readers know, for several weeks (it feels like forever!) I’ve been trying to work out the accuracy of the Low Histamine Food Lists found online.  What I discovered was really shocking.  The fact is, there is virtually no reliable data on which to base any kind of Amine-related food list and it appears that most lists are based on hunches, speculation or research so old the authors are dead.  It may turn out that these hunches are absolutely accurate: nutmeg really is high in histamine and so are pumpkins.  Or it might turn out that we’ve all been avoiding these foods for absolutely no good reason.

The whole subject of histamine is really quite complex.  What started out as a single article turned into an entirely new section of my blog called ‘Low Histamine Food Info’ which contains several new pages – just hover over the tab in the menu and you will see the pages listed.

If you’re feeling lazy and want direct links to the new pages here you go:

Please Read This First!

What is Histamine?

Diet & Histamine Intolerance

Diet & Mast Cell Disease

Histamine & Food: The Evidence

Histamine & Drugs (which is still being written, bear with me I’ll let you know when it’s available)

These pages are then followed by the existing Low Histamine Food List and Low Histamine Shopping List pages which remain largely unchanged.

I stress that the information in this new section isn’t exhaustive – there are a couple of companies which test for amines in food which I don’t have access to (although I question their accuracy) so I’ve only looked at free research which can be found online.  It is also only a personal interpretation of the data and I don’t claim to be any kind of expert at deciphering statistical analysis.  I’m just a sick girl, lying in my bed going round in circles trying to work out what any of this stuff means 😉

So, my friends, knock yourself out and have a read.  I’ll be interested to hear what you think and if you can add anything to the information please do let me know.

Dr Seneviratne Lecture

I was diagnosed with MCAD and HIT by Immunologist Dr Seneviratne who, IMHO, is the only person in the UK to see if you have suspected Mast Cell Activation Disorder.  He gave a lecture at EDS UK’s 2014 conference on mast cell disease and histamine intolerance and the link to EDS and other conditions such as POTS, and EDS UK have now placed a video of the lecture in the member’s section of their website.

Below is a summary of the salient points of Dr S’s talk, most of which were discussed with me at my appointment with him in 2013.

The immune system is made up of 3 components: white cells, antibodies and complement (which helps both the white cells and antibodies to work).  Mast cells are a type of white cell which, historically, the body used to fight parasites.  However, in modern times we now come into contact with very few parasites and the mast cell hasn’t got much to do.  Consequently in some people it can start to misbehave, reacting to things it shouldn’t because it’s basically a bit bored (my words, not his!).

As an immunologist Dr S worked predominantly with people who had either allergies or immuno-deficiency, ie the immune system was having an IgE reaction to things like animal dander/pollen/nuts or under-reacting to things it should be fighting.  However, he kept seeing patients who had immune reactions, particularly to foods, chemicals and drugs, but who didn’t fit the diagnostic criteria for either allergy or immuno-deficiency.

These patients were usually diagnosed with multiple chemical sensitivity but most doctors believed the symptoms were psychosomatic as conventional allergy tests showed they weren’t actually allergic to anything, with normal IgE results, normal tryptase levels and a normal amount of mast cells.  The mast cells were, however, obviously ‘twitchy’ and reacting willy nilly to environmental situations they should just be ignoring.

Other Consultants around the world were seeing the same thing and, around 10 years ago, collaborated to introduce Mast Cell Activation Syndrome for these patients.  This is now a recognised disease entity with strict diagnostic criteria.

About four years ago, Dr S began getting referrals of patients with MCAS from colleagues working in other fields and realized he was seeing a lot of people with both Ehlers-Danlos (hypermobile type) and/or POTS.  There appears to be a link between these two diseases and MCAS but as yet no-one knows why.

Mast cells produce around 30 chemicals when they react, including histamine, prostaglandins and cytokines.  Historically, histamine has been extremely difficult to measure as it starts to break down immediately after it leaves the body.  Conventional histamine tests, where the sample sits on someone’s desk for hours, then is transported to a lab where it often isn’t tested for days on end, gives very unreliable results.  Dr S, therefore, only uses one lab to test histamine following very strict protocols.  This test measures:

  • plasma histamine
  • urinary histamine
  • spot methyl histamine/creatinine ratio
  • histamine releasing antibody

He also measures serum tryptase.  In some people, all these tests will be normal yet they will still have symptoms of mast cell activation.   In the past 12 months, Dr S has therefore arranged for serum PGD2, 24 hour urine PGD2 and leukotriene samples to be sent to the Mayo Clinic in America for testing, which often show evidence of mast cell activation even when histamine levels are within the normal range.  He also recommends a gene test for the C-kit mutation because around 10% of people with MCAS will have a faulty C-kit gene (responsible for histamine activation).

Current drug treatment options for people with MCAS are poor and much more work is needed to find more effective medications.  Current treatment consists of:

  • Second generation H1 antihistamines, which should be given in high doses, up to 4 times the level used to treat conventional allergies.  Doctors aren’t used to prescribing higher than normal doses of antihistamines, however it is safe and if they do a Google search they will see information confirming this.  Do not use first generation H1 antihistamines, such as Piriton (chlorpheniramine) as they cross the blood brain barrier and can cause serious side effects if used long term, particularly in children.
  • Mast cell stabilizers such as Sodium Chromoglygate (Nalcrom) or Ketotifen.
  • Monteleucast, which blocks leukotrienes.  This is used as a first line of treatment in the USA, but as it only blocks leukotrienes and not other mast cell mediators, Dr S prefers to try mast cell stabilizers first.
  • If all else fails, patients often try supplements such as Quercetin.  However, as there is no literature available on their safety and efficacy Dr S doesn’t prescribe these himself.
  • Following a low histamine diet is important.

Histamine Intolerance (HIT) is a totally separate disease to MCAS, although it can produce almost identical symptoms.  HIT is due to low levels of DAO in the gut.  DAO is used to ‘mop up’ the histamine we all produce when we digest food, plus any histamine contained in the food itself.  When DAO is low it can’t deal effectively with this digested histamine, which builds up in the body to produce toxicity.  Some people have MCAS only.  Some people have HIT only.  While others have both MCAS and HIT.

Some patients will test negative for histamine, PD2 and leukotrienes yet still have mast cell activation symptoms.  Mast cells produce around 30 mediators and we currently only test for a handful of these.  If all evidence points towards MCAS, Dr S will do a trial of antihistamines and mast cell stabilizing drugs and see how the patient responds.  It is recognized, however, that many people with MCAS tolerate drugs poorly, if at all.

As a patient it’s brilliant to see that, finally, MCAS is being recognised and the link between mast cell activation and EDS has been discovered.  However, there is a long way to go in terms of educating the mainstream medical profession on mast cell activation and this will include turning long held beliefs on the way the immune system and mast cells work on its head.  We also have to find more effective treatments, particularly for those of us who have mast cell reactions to currently available drugs.  “The journey of a thousand miles begins with one step.”