Acute appendicitis is the most common pediatric surgical emergency, and a complicated disease associated with greater morbidity and resource use. However, institution-level cost data from Central and Eastern Europe remain limited. This study aimed to quantify the direct hospitalization costs of pediatric acute appendicitis in Western Romania and to assess whether disease severity, postoperative complications, and selected diagnostic or therapeutic factors were associated with higher inpatient costs. We conducted a single-center retrospective study including 1,535 pediatric admissions for acute appendicitis treated surgically between 1 January 2016 and 31 December 2025 at Louis Turcanu Children’s Hospital, Timisoara, Romania. Of these, 501 (32.6%) were classified as complicated appendicitis, and 971 (63.3%) patients were male. Median age was 11.08 years (IQR 8.58–14.50). Median length of stay was 6 days (IQR 4–8) overall, but was significantly longer in complicated than in non-complicated appendicitis (8 [7–11] vs. 5 [4–7] days). Median total hospitalization cost was 2,160 RON (IQR 1,406–3,356) overall, increasing from 1,710 RON (IQR 1,187–2,541) in non-complicated cases to 3,364 RON (IQR 2,432–4,618) in complicated cases. Cluster analysis identified four cost profiles; the highest-cost cluster had a median cost of 3,810 RON and the greatest proportion of complicated cases. Admissions with complications also had higher median costs than those without complications (3,441 vs. 1,806 RON) and longer hospitalization (8 vs. 5 days). Complicated pediatric acute appendicitis, therefore, imposes a substantially greater hospitalization burden, with disease severity and length of stay as the principal cost drivers.
