Keep it Simple, Laboratory Parameters to Predict Complicated Acute Appendicitis in Children Younger Than Five Years.

Background: The clinical presentation of acute appendicitis in the youngest age lacks specific signs and symptoms, and it is difficult to obtain an accurate clinical diagnosis. Once the diagnosis is made, it is necessary to determine if the appendicitis is simple and able to be managed non-surgically, or complicated, therefore requiring surgery. Together with the clinical picture and imaging, routine laboratory values play a vital role in this decision. The aim of this study is to evaluate routine blood in their ability to differentiate between complicated and uncomplicated acute appendicitis.

Method: A retrospective analysis was conducted from a single pediatric surgery department of all children 5 years of age or younger who underwent surgery for acute appendicitis between the years 2010-2020.

Results: 728 children were diagnosed with acute appendicitis, and 42 children were under the age of 5 years. There was a significant difference in the C-reactive protein, white blood cell count, neutrophil/lymphocyte ratio, and platelet/lymphocyte ratio in the complicated group versus the uncomplicated group. The value of these together for prediction complicated appendicitis were 84.8% sensitivity, 80.9% specificity, 82.8% positive predictive value, and 72.8% negative predictive value. These values were all higher than both the Alvarado score and the PAS (  <  .05).

Conclusions: C-reactive protein, neutrophil/lymphocyte ratio, and platelet/lymphocyte ratio are simple laboratory parameters that can help identify complicated versus uncomplicated appendicitis in children 5 years old or younger. These universal parameters may help guide the treatment and decision to operate on a difficult to diagnose population.