False negatives with FCP test

[Optimistic]

My son's latest Fcp just came in at 45 (normal is up to 120 with this lab). All other bloods were fine and he is assymptomatic other than some weird joint stuff occasionally. He sees dr in a few weeks and I'm not sure if he will order a scope after doing two in last 18 months. He gets a lot of monitoring because he is on SCD and omeprazole only and we want to be ready to pivot quickly to plan B if needed.

I keep reading about Crohn's patients who are appear to be doing well and then they learn inflammation is simmering or worse. I know about FCP studies for sensitivity and specificity in children and adults but I'm still not sure I can rest easy. Has anyone had a normal FCP and learn soon via scope or symptoms there was a problem? How much can I trust FCP? His levels were never crazy high even when at his worst.

 

[Clash]

At his worst result Chase's FC was 1700. The next after tweaking meds was done the same week as scope and MRI and they all correlated to simmering inflammation, FC was 300+.

After surgery he had an fc and scope the fc was 48(maybe 46?) and visually scope was clear but biopsies showed active inflammation and granulomas throughout.

 

[Maya142]

M's last FCP was 200, which isn't very high. However, a couple months ago it had been 26 and then 45 and since it was going up and she had some belly pain, we scoped.

We found visible inflammation (and two ulcers) in her TI, cecum and ascending colon. Everything else looked good.

Her highest FC was around 480. In her case, we know it can be as low as 26, so the moment we saw it rise, we acted. We are also watching carefully since she is now only on Imuran for her Crohn's.

Has he ever had an FC before? Do you know what is his normal or high for him?

 

[crohnsinct]

first can I say bravo to you for managing things minimally with diet but being very smart and monitoring things carefully! I am beyond impressed.

Second, you know I am obsessed with Fcp! No lab is perfect. However, Fcp has much less incidence than say crp or sed rate as coming up low and still finding inflammation. I think in all my time here there has only been maybe one person who had normal fc and been scoped and found active inflammation.

That said, Fcp can swing pretty widely day to day. Sometimes hundreds of points. This is why when we used it for t we pulled a test ever 8 weeks. Easier to spot trends that way and flesh out any weird outliers.

Sounds like you are in a good place but I always prepare myself for that "microscopic inflammation" talk

Fwiw. I had Fcp of 150 and had microscopic inflammation.

 

[Optimistic]

Maya - so M's was 200 at same time of scope? When it was in 40s did she have symptoms and how long was that before the scope?

Clash - how long after surgery was 40s score and then how long until the scope that showed the inflammation?

Yes Crohnsinct I'm always ready for that talk. I just read about Clash's son and now I am wondering. And he does take omaprozole as an off label treatment for the inflammation he had in duodenum. And of course there are studies now that show long term high doses is a problem but we are not changing anything. Risks and rewards, balance and all of that.

W has had many fC tests. My favorite was time he had to give a sample In lab bathroom while his siblings and I all waited and waited. The thing that worries me is at his worst in ICU it was 250. So his high isn't too high. Some labs say 50 is in range of trouble and if he is in 40s which is where he stays, that is close, right? I know we shouldn't try to solve problems we don't have yet and I should be only grateful but I don't want to be naive and stupid. I know now he had Crohn's for several years before the flare that led to diagnosis. Plus two different Drs have said he is medically unusual (presented so horribly initially compared to now) and that is something you don't want to be, good or bad.

 

[Maya142]

No symptoms when she was in the 40s. That FC was done in December. Then the FC that was 200 was done in April. Scope was June 1st.

She has had some belly pain (lower right side) and some diarrhea and urgency, mostly in the last month and a half or so.

We are planning to increase her Imuran dose and added Entocort.

I can see why you're worried if his FC was 250 when he was in the ICU! But honestly, the only other way to really "see" what's going on is to do a scope or MRE.

No easy answers .

 

[Optimistic]

I'm sorry about M. I hope the pain and urgency (and of course that inflammation) are alleviated by the entocort and increased Imuran. Steroids were wonder drugs here - until it was time to wean.


I think I'll just push for a scope and plan that will happen each year.

I'm off now to google what FC scores "regular" people get.

Crohnsinct - what did they decide caused your issue?

 

[my little penguin]

Regular people get below 50 ( for some labs )
And below 160 other labs

Ds ends up with a scope a year typically because other things don't show much
And we are left wondering

 

[Maya142]

I should add that between December and April, we took M off an anti-TNF (Simponi) and switched to a different class of biologic for her AS. We knew her CD flaring was a risk.

She actually does not have that many symptoms and really just had occasional belly pain when we decided to check her CD, which made us feel very grateful that we caught it early.

I think since he's not on any meds, better to be safe and check things out, though scopes are really no fun!

What are his joint symptoms? Joint issues can flare at the same time as Crohn's or independently (or of course, be completely unrelated to the Crohn's!).

Fwiw, my older daughter who has AS but not Crohn's (and is always on NSAIDs) has always had an FC under 50. We have checked several times because of the family history.

 

[Clash]

The fc that was 48 was 9 months after surgery if I remember right and the fc was a couple weeks before the scope. Like I said, visually his scope looked great it was only when the biopsies came back that we knew that at the cellular level there was inflammation and granulomas.

 

[crohnsinct]

Most studies to test the feasibility and reliability etc of FCP state normal should be under 50 for "regular people". However, most labs are now using the 160's cut off. So regular people under 160.

There is also the theory that FC is more reliable for colonic disease than small bowel, although our doc doesn't subscribe to that theory and my girls disprove it.

You have to know your kid. More than a few people here have charted their kid's sed rate and can tell way before they go over normal that they are heading into a flare. The issue is, what is normal for your kid.

The best thing to do is to pull an FC right before prep and see how it correlates to the scope results.

For O with the 150 FCP and the microscopic inflammation, we did nothing. Then in fall she crept up to 450 and was a little symptomatic...upped mtx 2.5 mg's. FC came down to 250 in a few months and decreased MTX. Our doc seems comfortable with FC sitting at just above normal. I feel comfortable with weekly scopes and daily fcp:ylol:

 

[Catherine]

From our experience the lower level you can get for faecal calprotectin is <19 and above 50 is high.

So less <19 meaning no imflammation at all. These are results for myself and my youngest daughter.