Difficulties in indicating appendectomy; diagnosis of appendicitis in patients with normal white blood cell count

Abstract

Objectives: Even after 130 years have passed since the first appendectomy, diagnosing acute appendicitis can still be challenging. The objective of this study was to investigate clinical, imaging and laboratory findings of patients diagnosed with acute appendicitis in order to determine whether white blood cell count is helpful in the diagnosis. Materials and Methods: Parameters of Alvarado score, patients’ complaints, physical examination and laboratory findings were recorded. Appendiceal diameters of patients detected with ultrasound (US) were also recorded. Results: Of the 98 patients, 89 patients (91%) had an appendiceal diameter wider than 8 mm and 9 patients (9%) had an appendiceal diameter of 8 mm and smaller in the preoperative US. Pathology was normal in 8 out of 9 patients (89%) with a diameter of 8 mm and below; and 9 out of 89 patients (9%) with a diameter above 8 mm (p<0.05). Sensitivity and specificity of the 8-mm cut-off was 99% and 47% respectively. Positive and negative predictive values were 90% and 89% respectively. Conclusion: Distribution of pathology results with respect to appendiceal-diameters revealed that there was an obvious threshold between normal and pathology-proven appendicitis. This outcome highlights the importance of imaging in the diagnosis.

Keywords

• Appendicitis,Diagnostic ultrasound,White blood cell count

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