The formula Prometheus uses to determine IBD is pretty complicated; it's not simply a matter of seeing whether any of the values are above the references. You can be below the references in all categories but still have IBD. Increasing levels, above their reference levels, correlate with more severe disease and with complications. So it's not surprising for mild and/or early Crohn's to have no values above reference level.
I think I understand. Just received a copy from GI and I didn't understand it nor did the values look indicative of Crohn's although it was marked IBD Predicted and Crohn's Disease Predicted. This was the Prometheus IBD Serology 7 Test:
ASCA IgA - 12.6
ASCA IgG - 15.8
Anti OmpC IgA - 11.5
Anti-CBir1 - 20.5
AutoAntibody - <12.1
Pattern - Not detected
Sensitivity - Not detected
The sheet I received also had a box labeled General Test Information, wasn't sure if it was the test percentage in general, or percentages of each patient's results?
Sensitivity: IBD 93%, CD 88%, UC 93%
Specificity: IBD 95%, CD 98%, UC 97%
PPV: IBD 90%, CD 93%, UC 98%
NPV: IBD 90%, CD 93%, UC 98%
I haven't had a chance to speak with my GI about the test since I have to have nodules in the lungs checked out first before starting Remicade, so I probably have a few weeks before we meet.
It's been eight months since I had to seek attention after severe diarrhea, (diarrhea for 20 years), dehydration, fever, lethargy night sweats and cramping. In March a CT scan dx'd Crohn's but later, the Pill cam and SFTB series showed no signs. I had a fistula since Jan. 2006 but my GI and 2 colorectal surgeons basically didn't believe me, or said it had to abscess before they could locate it. In August I went to the Cleveland Clinic and they found two pouches communicating and an opening into the anus, without an abscess present. They had me in a week later for a fistulotomy. Either it didn't close completely, or I have a new abscess/fistula present that is abscessing now.
Previous blood work showed protein elevation and 99% my WBC was high, but the colonoscopy biopsy was negative. The endoscopy showed GERD/Reflux, Gastritis, but the positive CT scan was ignored. Symptom wise it's text book with few exceptions. I've sinced changed GI's and that is why I had the Prometheus test, but now after all this time I don't know what is considered enough info and what isn't. I've read too much and no procedure seems absolute without critics.