Hyperbilirubinemia, Leucocytosis and Differential Neutrophil Count in Appendicular Perforation-A Comparative study

Appendicular perforation is the main source of morbidity, and mortality inthe otherwise benign course of acute appendicitis. Inflammatory markers such as total leucocyte count(TLC) and differential neutrophil count (NC) have been investigated for their potential to predict complications in appendicitis, along with newer markers such as serum bilirubin (SB). This study aims to compare the utility of these laboratory investigations, individually or when combined, for the diagnosis or exclusion of this condition.

A prospective study of 116 patients of clinically diagnosed acute appendicitis was performed. Patients were grouped on the basis of histopathological examination of appendectomy specimens into two groups-acute uncomplicated appendicitis (AA) and complicated appendicitis (PA). The pre-operative investigations were correlated and compared using various statistical methods, ROC curve analysis and likelihood ratios.

ROC curve analysis showed SB to have excellent discriminatory power in cases of the appendicular perforation (AUC-0.95, CI-95%), for both diagnosis (+LR 12.21) and exclusion (−LR 0.10). Both TLC and NC showed good sensitivity (72.7% and 77.3% respectively) but poor specificity (28.7% and 48.9% respectively) for differentiating PA from AA. AUC was 0.58 for both, signifying no clinically useful discrimination. Combination of TLC to SB showed improvement in specificity (97.9%) but had low sensitivity (72.7%).

Hyperbilirubinemia provides the highest diagnostic accuracy for PA. TLC and NC did not provide any discriminatory value for PA. SB can be an invaluable adjunct to clinical decision making for identifying the severity of acute appendicitis