Category Archives: Crohns Disease and Low Platelet Count; Azathioprine

The Difficult Patient

I like to think that I’m a good patient. I very rarely forget to take my medication; I always turn up for appointments; I try to enter the consulting room with a positive attitude and clutching a list of questions.

…but I’m also a difficult patient. I think it’s true of any IBD patient that we are “difficult” because it is likely that on first presentation to our GP our symptoms could have a number of possible explanations. At least more doctors are becoming aware of IBD as an avenue for investigation. It took 8 months for my positive diagnosis of Crohn’s disease, via “nerves” and “spastic colon” along the way.

The difficulty continued. My platelet count dropped dramatically (thrombocytopenia). The most likely explanation? “It was the azathioprine.” So I stopped the azathioprine, my platelets showed no improvement and I ended up having surgery to remove a stricture.

Azathioprine is known to potentially affect the blood which is why we should have regular blood tests when taking it. Although my platelet count was around the 70 mark (usual range 150 – 400), I was asymptomatic. If I cut myself I didn’t bleed any more than usual and after several visits to see the haematologist it was decided to park the issue as it wasn’t affecting any other treatment. I had been in remission and Crohn’s drug free since surgery.

But what if the Crohn’s started to flare again and my gastro consultant decided the best treatment would be to restart the Aza? I put this to him and he agreed that we should un-park the question and try to find out whether the drug was to blame.

Off to see the haematologist again and two bone marrow biopsies later it was decided that Aza was the probably the guilty party, had attacked my bone marrow which in turn suppressed platelet production. (…..not everyone agrees)

The second “difficulty” was when I started vomiting blood, an incident that I have mentioned many times before. Into our local A&E and then admitted as an in-patient. The consultants there were expecting to find an ulcer. To confirm their suspicions they shoved a camera down my throat and were surprised to find esophageal varices. A simple-to-treat ulcer was actually something a lot more sinister.

One ultrasound scan later and it was identified as portal vein thrombosis. Time to pass me back into the care of my usual hospital. Treatment would involve both a hepatologist and haematologist. At my first meeting with the hepatologist I asked what could have caused the blood clot in my portal vein. He said that the most likely explanation was that it resulted from peritonitis brought on by a perforated bowel over 30 years previously. I have to admit I still struggle with this explanation. Why did it take 30 years to come to a head? Result – beta blockers and proton pump inhibitors.

The haematologist suggested that I started taking blood thinners to combat the threat of further blood clots. I really didn’t want to take any more medication than strictly necessary so we did a risk analysis and concluded that it was 50/50 for and against. Result – no warfarin. Another issue successfully parked.

Then came the jaundice as a result of gallstones. I met with upper GI surgeons at both my local and Kings College hospitals. The usual treatment would be to whip out my gallbladder using keyhole surgery but, of course, my case is not so simple. Previous laparotomies have left scar tissue and adhesions that would preclude a keyhole operation. Then an MRCP scan showed that the varices, that had grown down my throat, had also grown around my gallbladder.  Aaah!

What have we concluded? The choices are to operate now to prevent a problem in the future “that might never happen” or to postpone the decision and review again in 6 months time. He was minded to go with this second option. I wholeheartedly agreed with him.

…and finally there’s the little matter of conflicting test results. As it was the subject of my last post I don’t intend to repeat it here but it leaves me with questions. Is the “wait and watch, let’s park that issue” a valid strategy or best option in this instance. If I asked for further investigations to be done would I simply be using up valuable NHS resources carrying out tests that might make no difference to, or even worsen, my QOL? Would it even be clear which further tests could be carried out? As I said in that previous post, curiosity is getting the better of me but I’m not going to lose any sleep over it. That’s one of the advantages of writing a blog. You can get all your thoughts down in one place and then, you guessed it, park them.

Maybe there are no clear cut answers but I’m starting to feel that my “difficult patient” status can only get worse as the ageing process kicks in. Oh for a simple life.

The Aza Conundrum

For nine years between (1999 to 2008), taking Azathioprine (Imuran) in varying doses between 150mg to 200mg/day successfully kept surgery at bay. Any Crohn’s flare-ups were dealt with by short courses of steroids. Then a series of routine blood tests showed that my platelets were dropping and it was concluded that Azathioprine was the most likely cause. I stopped taking it and within 2 years was undergoing major surgery.
I drew a graph to try and spot any correalation between the drug dose and the platelet count. I was expecting to see the count bounce back once I stopped taking Azathioprine and it did so the first time but when I started/stopped for the second time the platelets remained low. I’m guessing at that point the bone marrow was already damages. The only way to investigate further was to have a bone marrow biopsy.


In 2012 I went to see a haematologist and she explained some possible causes of a low platelet count :

increased destruction – the body is producing sufficient but something is destroying a number of them, possibly drug induced

decreased production – the body isn’t producing the right number in the first place which could be down to bone marrow failure.

We also discussed another factor – the implication of my enlarged spleen. Enlarged spleens can hold increased numbers of platelets and therefore the number released into the bloodstream is lower hence the lower count.

I had the bone marrow biopsy and afterwards received an email saying: “your bone marrow is being discussed with the histopathologist and we will write to you with the results. We will see you in clinic later in the year.” (I had to look up histopathologist – someone who carries out microscopic examination of tissue in order to study the manifestations of disease.)

I replied asking for an indication of what they had found. The response was that it would be easier to discuss the findings in clinic.
What did that mean? Nothing to worry about, it can wait, or it’s serious and we want to tell you face to face? Time for another short email along the lines “…I wonder if you could at least put my mind at rest that you haven’t found anything too serious….”

Within a few minutes this came back :
“We have reviewed your bone marrow in our multi-disciplinary meeting and there is nothing sinister to report. The findings suggest that your marrow is underproducing platelets rather than it being an immune cause that we had presumed secondary to your longstanding history of Crohn’s. This may be due to previous azathioprine use. We can discuss this in person and in more detail at your next appointment. In the meantime – I hope this reassures you.”

The appointment duly arrived. The haematologist started our conversation with: “Yours is not a simple case…..”. She had printed out the biopsy report that had been discussed at their MDM and the initial conclusion was that they were “in keeping with early/low myelodysplastic syndrome, histologically suggesting MDS-RCMD.” She knew that I would have looked this up on the internet and would have spotted the potential links with leukemia. That’s why the report hadn’t been emailed to me. [If I had Googled MDS I would have found the following – “The disease course is highly variable, from indolent to aggressive with swift progression to acute myeloid leukaemia (AML) in 30% of cases.” I think she was right to want to discuss it in person.]

She was not completely happy with this MDS conclusion because a bone marrow biopsy looks at two substances – the marrow itself and the aspirate (fluid). When the procedure was carried out the doctor was unable to obtain good aspirate slides as the blood in the samples kept clotting. After several attempts, but with little success, they had decided to concentrate on obtaining a good bone marrow core.

She described it as “like having a three piece jigsaw from which two of the pieces are missing.” At the next MDM they had discussed the results again and decided that, in my case, it was unlikely to be MDS but would recommend a further biopsy to get useable aspirate samples. “How would you feel about this?” I replied that I really wasn’t fussed. If it would help narrow down the diagnosis then the sooner the better. Next time they would use heparin, a blood thinner, with the sample needle as it should prevent the blood from clotting.

If the diagnosis wasn’t MDS then why the low platelets? The most likely cause was a combination of long-term Crohn’s and taking azathioprine. The biopsy had shown that the marrow was under-producing platelets rather than being over active and eating them up. I had been unaware that there was a potential link between Crohn’s and bone marrow.

The MDM had then gone on to discuss what the implications for treatment would be if it was/was not MDS. In either case the preferred course for treatment, at this stage, would be “do nothing” unless I was to have any procedures that could cause bleeding or that required surgery. A supply of platelets should be made available if either of these were needed. The difference in approaches would be in the monitoring regimes and we would discuss this further after the next biopsy results were available.

Back to reception to book up another biopsy and a three-month follow-up appointment.

In the meantime I had a routine gastroenterology appointment and I mentioned the need for a second bone marrow biopsy. Now you would think that a doctor who doesn’t bat an eyelid when sticking a camera up a patient would be pretty much hardened to all medical procedures, but the mere mention of the bone marrow biopsy was enough to make him squirm. He asked me if I was OK having the biopsy as it was the one test he really wouldn’t want to undergo himself! Strangely enough he wasn’t the first person to express that emotion.

A couple of weeks after the second biopsy I was back to see Haematology. When I went in for the pre-appointment blood test the phlebotomist asked me if I knew why she was also taking an “histological” sample. Since I didn’t know what “histological” meant I was of little help. (Of course I know now! It’s the anatomical study of the microscopic structure of animal and plant tissues).

The haematologist explained that one of the biopsy samples, which should have gone for histological testing, had either been mislaid or mislabelled so did not make it. This is why she had rung me a few weeks back to explain the situation. I’d forgotten about this. She had, however, looked at the other slides from that second biopsy and these were fine.

The missing sample had been discussed with the chief histologist and he suggested doing a specific type of blood test which had proved to be 60% effective in spotting problems, if there were any. The results would be available in a week’s time. The alternative was to have a third bone marrow biopsy but they didn’t want to put me through that again. I suppose I could have made a fuss about the missing slide but I couldn’t see what good it would do.

CURRENT SITUATION
When I saw the haematologist in February 2015 she described my bone marrow as being “a four cylinder engine running on only three” and therefore not delivering the right quantities of platelets.
What is the long-term prognosis for the thrombocytopenia? It should not affect the other issues I have – Crohn’s, potential PSC, PVT, but I must avoid the use of azathioprine in the future. It’s important not to get hung up on the numbers as I am asymptomatic and do not bleed profusely if I cut myself.

What could have caused the low platelets? There are no signs of marrow abnormalities that could point to a more sinister conclusion (leukaemia), therefore the cause is most likely to be drug-induced long-term use of azathioprine. The official description was “asympomatic thrombocytopenia. Therapy related secondary dysplasia on bone marrow morphology – most likely due to Azathioprine”.

Do I need treatment? No, but must look out for any signs of starting to bleed more easily. Monitoring? Six-monthly blood tests and outpatient appointments (which subsequently became annual and then dischargeded).

WHAT NEXT?
A couple of new issues have arisen – borderline thyroid level + possibility of cholecystectomy – so it seemed like a good idea to book another appointment with Haematology to discuss further. Watch this space