Clinical features and treatment outcomes of infantile appendicitis: a multicentre study

Appendicitis in infants is a life-threatening condition that is seldom studied. Our purpose was to conduct a comprehensive evaluation of appendicitis in this age group. This was a multicenter retrospective study. Patients aged under one year with surgically confirmed appendicitis during January, 2010 to May, 2022 were identified from four institutional databases. The patients were grouped as neonates or older infants based on their age at the onset of symptoms associated with acute appendicitis. The study encompassed 98 infants, with median age of 66.5 (IQR, 13.8-176.0) days. Neonates were more likely to exhibit abdominal distension (64.9%) and fever (56.8%), while older infants more frequently presented with fever (88.5%) and vomiting (49.2%). Most patients (76.5%) were misdiagnosed during their initial clinical encounter, with a -rate was 3.1% (3 deaths), with neonates exhibiting a rate of 5.4%, and older infants 1.6%. Compared to older infants, neonates showed a higher incidence of appendiceal perforation (OR, 2.9; 95%CI, 1.1-8.1), mechanical ventilation (OR, 9.5; 95%CI, 3.1-29.2), and ICU admission (OR, 16.1; 95%CI, 5.6-45.7). However, there were no significant differences in mortality rates, 30-day readmission rates, and surgical complications between the two groups.

Although most infants with appendicitis were misdiagnosed during the first clinical encounter, the observed mortality rates were considerably lower than previously reported. While neonates and infants over 28 days displayed differing clinical presentations and disease severity, their outcomes were similar.

• Appendicitis in infants is a critical yet underemphasized health concern, often misdiagnosed at initial clinical encounters due to its atypical presentation and non-specific symptoms. • The mortality rates in the neonates with appendicitis was 23% during the past decades.

• The neonates and older infants displayed differing clinical presentations and disease severity. The treatment outcomes were similar. • The mortality rate for infantile appendicitis (3.1%) was significantly lower than historically reported.