Objective
The aim of the study was to evaluate the diagnostic yield of preoperative high serum total bilirubin (TB) for cases of appendicitis in conjunction with clinical and other laboratory findings.
Patients and methods
The current study included 417 children presenting with right iliac fossa pain. All patients underwent clinical examination and gave blood sample on admission for estimation of serum TB and C-reactive protein (CRP) and total leukocytic count (TLC) and underwent surgical exploration and management according to operative findings.
Results
Surgical exploration defined 134 cases of complicated appendicitis (CA), 219 cases of simple appendicitis, and 64 cases of noninflamed appendix. Mean preoperative TLC and serum CRP showed high sensitivity (88.7 and 83.6%, respectively) for detection of acute appendicitis (AA), despite the lower specificity of CRP for diagnosis (57.8%), whereas the specificity rate of elevated TLC was 71.9%. For discrimination between simple appendicitis and CA, elevated serum CRP showed higher specificity compared with elevated TLC (70.3 vs. 65.8%) despite the higher sensitivity of elevated TLC compared with elevated serum CRP (91.8 vs. 80.6%). Serum TB showed the highest specificity rate for defining cases of AA and CA (79.7 and 86.3%, respectively) despite the low sensitivity for both. Receiver operating characteristic curve analysis defined the severity of rebound tenderness in the form of significant, sensitive, and elevated TLC as the most significant specific predictor for AA. Serum TB greater than 1 mg/dl was the most significant specific predictor for the diagnosis of CA.
Conclusion
Combined estimation of TLC and serum CRP and TB improves the diagnostic yield by combining the high sensitivity of TLC and CRP with the high specificity of TB, allowing early detection of cases that could develop CA and enabling better decision for patient discharge.