Using ultrasonographic features in pediatric Crohn's disease activity index severity.

Background: The diagnosis and follow-up of Crohn's disease (CD) often require invasive instrumental examinations, which carry a high risk of iatrogenic injury. This study aimed to determine the frequency of ultrasound features in each stage of the Pediatric Crohn's Disease Activity Index (PCDAI).

Methods: This cross-sectional study included 22 pediatric patients with Crohn's disease. Disease activity was assessed using the PCDAI. The state of CD activity was categorized into four groups: remission (PCDAI scores less than 10), mild (PCDAI scores of 10-27.5), moderate (PCDAI scores of 30-37.5), and severe (PCDAI scores > 40). Clinical data collected included the thickness of the ascending colon loop, the thickness of the ileal loop, the number of lymph nodes, the short-axis diameter of lymph nodes (mm), spleen span, presence of free fluid, fistulas, liver echogenicity, vascularity around the loops, lumen narrowing, terminal ileum compression, mesenteric fat hypertrophy, intestinal wall and mesenteric fat echogenicity, and Superior Mesenteric Artery indices. These data were documented for analysis.

Results: As disease activity progressed from mild to severe, intestinal wall echogenicity, fat echogenicity, mesenteric fat, vascularity, and lumen narrowing significantly increased (P < 0.05). The mean ileal loop thickness also significantly increased (P = 0.005), rising from 2.12 ± 0.58 in mild cases to 4.49 ± 1.43 in severe cases. However, the mean ascending colon loop thickness, the number of lymph nodes, the short-axis diameter of lymph nodes, and spleen span were not statistically significant (P > 0.05). Changes in the superior mesenteric artery indices across the different PCDAI phases were also not statistically significant (P > 0.05).

Conclusions: Ultrasound is a convenient and reproducible tool for monitoring CD activity in pediatrics. This study demonstrated significant findings, including the increase in intestinal wall echogenicity, fat echogenicity, mesenteric fat hypertrophy, vascularity, and lumen narrowing as the disease activity progressed from mild to severe. Particularly, the mean ileal loop thickness showed a significant increase in the severe phase compared to the mild phase.