question on diagnosis terminology

Is there a distinction between the "severity" part of the UC diagnosis and the part that describes how much of the colon is affected?

In other words, could you have "mild to moderate" pancolitis?

To me, they seem distinct, i.e. that the severity relates to how deep the ulcerations are in the tissue, but I've never asked.

Also, speaking of depth, is a CT scan the only way to determine how much of the lining of the colon (in terms of depth) is affected or could a colonoscopy show that?

Okay as long as I'm asking technical questions, here's one more -- have you ever examined the results of a complete blood count done during a flare? I just had one and my white blood cells are elevated (no big surprise) but so are my platelets, and my lymphocytes and monocytes are elevated. I think this is all consistent with a UC flare but I'm curious (I got the results yesterday but my doc is out of town until next week so I can't ask him just yet).

Here are my numbers for your reference.

I am in a severe flare since April 20th.

CRP 1.2

Neutrophils %, automated count	76	41 - 79	%
Lymphocytes %, automated count	16	13 - 44	%
Monos %, auto	7	5 - 14	%
Eosinophils %, automated count	0	0 - 6	%
Neutrophils auto count	4.9	2.1 - 7.4	K/uL

My numbers are normal except for Hgb and Hematocrit as due to bleeding I am anemic...

WBC COUNT	6.4	3.5 - 12.5	K/uL
Red blood cells count	4.00	4.10 - 5.70	M/uL
Hgb	11.9	13.0 - 17.0	g/dL
Hematocrit	35.5	39.0 - 51.0	%
MCV	89	80 - 100	fL
RDW, RBC	13.1	12.0 - 16.5	%
Platelets count	319	140 - 400	K/uL