Role of leukocyte count, neutrophil percentage, and C-reactive protein in the diagnosis of acute appendicitis in the elderly.

Leukocyte count, neutrophil percentage, and C-reactive protein (CRP) have been shown to give valuable information in the diagnosis of acute appendicitis. However, whether these laboratory tests have the same clinical applicability in the elderly as in young patients remains unclear. This retrospective study aimed to clarify the role of these tests in the diagnosis of acute appendicitis in patients aged 60 years or over. Eighty-five consecutive elderly patients underwent appendectomy for suspected acute appendicitis during a 30-month period. Histologically verified appendicitis was found in 77 of the 85 patients (90.6%). There was no significant difference in leukocyte counts or CRP values between patients with acute appendicitis and those with a normal appendix. The sensitivities of leukocyte count, neutrophil percentage, and CRP in the diagnosis of acute appendicitis were 71.4 per cent, 88.3 per cent, and 90 per cent, respectively, while the specificities were 37.5 per cent, 25 per cent, and 37.5 per cent, respectively. Of 77 patients with acute appendicitis, only two had all three tests simultaneously normal. In conclusion, patients with normal results in all three tests are highly unlikely to have acute appendicitis and should be evaluated with extra caution before surgery.