Ultrasonographic characteristics of neonatal appendicitis: a case series

Background: Neonatal appendicitis is a rare but critical condition that presents diagnostic challenges due to its nonspecific symptoms and clinical manifestations. Early and accurate diagnosis is crucial for reducing the high mortality rates associated with this condition. Abdominal ultrasonography plays a pivotal role in identifying characteristic signs of appendicitis in neonates. This study aimed to investigate whether neonatal appendicitis can be diagnosed with abdominal ultrasonography by identifying its specific signs.

Methods: This study reviewed 20 consecutive cases of neonatal appendicitis confirmed through surgery at a National Medical Center. Preoperative abdominal ultrasonography was analyzed for direct and indirect signs of appendicitis.

Results: Our study included neonates with a mean age of 13.0 ± 7.1 days. The appendix was identifiable in 13 out of 20 cases (65%). The mean outer diameter of the appendix was 4.6 ± 1.8 mm. Eight cases had appendix diameter ≥ 4 mm. Fluid accumulation within the appendiceal cavity was noted in 6 (30%) patients, and peri-appendiceal fluid accumulation was detected in 5 (25%) patients. Ultrasonography revealed appendiceal perforation in 12 out of 16 cases (75%). The indirect signs of neonatal appendicitis included right lower quadrant (RLQ) abscess, pneumoperitoneum, and thickening of the intestinal wall and mesentery in the RLQ.

Conclusion: Most cases of neonatal appendicitis may be diagnosed through abdominal ultrasonography by identifying both direct and indirect signs. Future studies with larger patient cohorts are needed to improve ultrasonographic diagnosis of neonatal appendicitis.