What histological features are characteristic of Crohn's disease?

Transmural inflammation and fissuring ulcers are definitive characteristics of Crohn's disease. This condition affects any part of the gastrointestinal tract but is most commonly seen in the terminal ileum and colon. The inflammation in Crohn’s disease penetrates through the full thickness of the bowel wall (transmural) rather than being confined to the mucosa and submucosa, as seen in some other conditions like ulcerative colitis.

Fissuring ulcers are a result of this transmural inflammation and can lead to complications such as the formation of strictures or fistulas. These ulcers are often deeper and more irregular than those found in other gastrointestinal diseases, making them a significant histological hallmark of Crohn's disease.

The other options do not accurately describe the features of Crohn's disease. The absence of neutrophils and ulcers does not reflect the disease's inflammatory nature, while being limited to the mucosa and submucosa pertains more closely to ulcerative colitis. Finally, the absence of inflammation contradicts the nature of Crohn's disease, which is characterized by chronic inflammatory processes throughout the bowel wall.