With some doctors you need to ask for the calprotectin test - they don't all know about it. My partners sister had to ask her GP for it last month - the GP said she'd never heard of it!
It is such an important test though as if your result is raised and you have long term gut issues then you should be referred on for further investigations.
If you are worried about whether it could be Crohns rather than IBS then I would ask for the calprotectin test.
Maybe look up the test - there is information readily available online that will explain how it works xxx
In terms of the blood tests, my inflammatory markers (ESR & CRP) were normal too. I was told by one GP that they would expect them to be raised if I had Crohns. (This isn't always true though and certainly wasn't for me). I was only referred for further tests because my calprotectin was high.
... By systemic, I meant symptoms any where else in your body rather than just the gut.
Everyone is different and not everyone will have the same as I did but to give you some idea, my symptoms, in addition to my gut issues, included:
peripheral joint pain, back, hip, rib pain, eyes affected, foggy head - couldn't focus or concentrate, ringing in my ears, acid reflux, a cough for months (from the reflux I think), ridiculous fatigue - I was having to go back to bed during the day, I couldn't drive my car, I couldn't even carry an empty shopping basket at the supermarket on one day - the fatigue would come on suddenly and knock me out. I had sore lymph nodes, mouth ulcers, would get a temperature. My joint pain was worse in a morning - I couldn't sit up to get out of bed, I had to roll out onto the floor and then couldn't stand up fully. The plantar surface of my heels was painful to walk on.
Bloods showed that I was anaemic too.
... as awful as all of this sounds, and was, I now have no symptoms. If it does turn out to be Crohns that you have, please know that it is treatable. xxx
My mums symptoms were different to mine. She had constipation issues rather than loose stools. She had nausea, loss of appetite, she lost a huge amount of weight. She had the extreme fatigue too. She was very ill and went through a tough time around the time of her diagnosis but now is very fit and active - she has no symptoms either.
If you are not satisfied with what your GP has said then do push for further tests to try to find out what is going on xxx