Diagnostic accuracy of the Tzanakis score for acute appendicitis in a resource-limited setting: A tertiary hospital-based survey

Abstract

Background: The management of acute appendicitis remains challenging with high peri-operative morbidity and mortality due diagnostic delay or high negative appendicetomy rates due to aggressive surgical approaches. CT scan is accurate for pre-operative diagnosis but not available or affordable in all settings. There remains a need for an affordable yet accurate tool for diagnosing acute appendicitis in the resource limited setting. 

Methods: To determine the diagnostic accuracy of Tzanakis score in the preoperative evaluation of patients with acute appendicitis, we conducted a descriptive cross-sectional study at Mulago Hospital in Kampala, Uganda. Eligible consenting patients diagnosed with acute appendicitis consecutively underwent Tzanakis scoring and appendicectomy. Appencieal samples were sent for histological examination. Sensitivity, specificity, positive predictive value, negative predictive values, and diagnostic accuracy of the Tzanakis scoring system were calculated, relative to histological examination. 

Results: We enrolled 160 participants of mean age 30.4 years with male:female ratio of 2:1. The Tzanakis score had sensitivity of100% (95% CI 98-100), positive predictive value 97 % (95% CI 95-99), specificity of 64% (95% CI 31-89), negative predictive value of 100%, and overall diagnostic accuracy of 98% with 3% negative appendectomy rate. 

Conclusions: The Tzanakis score is found to be a sensitive and specific tool that should be considered for preoperative diagnosis of acute appendicitis in resource limited settings. 

Keywords: appendicitis; appendicectomy; acute abdomen; diagnosis; Tzanakis score; Uganda