**Question:** Which of the following is the earliest sign of ulcerative colitis on double-contrast barium enema study?

**Core Concept:** Ulcerative colitis is a type of inflammatory bowel disease (IBD) that affects the colon, causing inflammation and ulceration. Double-contrast barium enema study is a diagnostic procedure used to visualize the colon and identify abnormalities such as ulcers or inflammation.

**Why the Correct Answer is Right:** In the context of ulcerative colitis, the earliest sign on a double-contrast barium enema study would typically be the presence of ulcers within the affected colon. These ulcers can appear as areas of increased contrast uptake, which can be indicative of mucosal inflammation and damage.

**Why Each Wrong Option is Incorrect:**

A.
B.
C.

Incorrect options A, B, and C are likely referring to the presence of inflammation or abnormalities like strictures, but the specific focus here is on the earliest sign, which is ulcers.

**Clinical Pearl / High-Yield Fact:**

The presence of ulcers on a double-contrast barium enema study can serve as a crucial indicator of ulcerative colitis, especially when combined with other clinical and endoscopic findings.

**Correct Answer:**

D. Ulceration

The correct answer is D, "Ulceration," as it represents the earliest identifiable sign of ulcerative colitis on a double-contrast barium enema study. This finding is indicative of mucosal inflammation and damage due to the disease process.