Diagnostic accuracy of total leucocytic count and C-reactive protein in acute appendicitis

ABSTRACT

Early and accurate diagnosis of acute appendicitis [AAp] is still a difficult problem especially in patients with questionable symptoms and signs. The current study was designed to determine the accuracy of repeated total leucocytic counting [TLC] and measurement of serum C-reactive protein [CRP] level in the diagnosis of suspicious Ap and to compare this with the surgical clinical diagnosis. The study comprised 83 patients with acute abdominal pain, after clinical examination with special respect to localization of pain to right iliac fossa, and the presence of rebound tenderness and abdominal wall guarding, two blood samples were taken; the first [SI] at admission and the second one 4 hours later [32], for TLC and estimation of serum concentration of CRP. Histopathologic examination of the resected appendices disclosed normal appendix [NAp group] in 13 patients with 16% negative laparotomy rate while 66 patients had acute appendicitis [AAp group]. Abdominal wall guarding is the most specific clinicalfindingforAAp with a 95.2% sensitivity, 61.1% specificity and 88.6% accuracy rate. Ttiere was a significant increase in TLC and CRP value in AAp group compared to NAp group and in S2 sample versus SI. TLC of S2 sample was specific for AAp with a 98.5% sensitivity, 92.3% specificity and 97.5% accuracy rate. However, CRP showed a higher sensitivity and specificity in the presence of gangrenous or perforated appendix [Ap] There was a positive significant correlation between diagnosis of AAp and TLC S2 sample, [r=0.956, P<0.001]. Moreover, there was positive significant correlation CRP value in S2 sample and pain localization, and abdominal wall guarding [r=l, P<0.001] and the presence of rebound tenderness [r=0.937, <0.00l]. In conclusion, the increase in TLC is an early marker for appendiceal inflammation and its persistent elevation indicating AAp, whereas CRP level usually increases markedly only with complicated Ap. AAp seems to very unlikely in patients with a normal TLC and CRP value, even if clinical symptoms and signs indicated AAp