Non Pathological Appendicitis

Appendicitis is one of the most common and challenging surgical emergencies, and can lead to appendicular perforation and peritonitis, which are associated with high mortality and morbidity. Making the decision for a surgical operation based only on the patient’s signs and symptoms results in removing non pathological appendices (negative appendectomy) in 15% to 30% of cases.(1, 2)
For this reason, a number of diagnostic modalities have been proposed, including laparoscopy, clinical scoring systems, ultrasonography, CT scans and MRI.
Alvarado score as a representative for clinico-laboratory scoring system has been chosen in this study as it's easy to be done rapidly in emergency unit, well tested and widely available scoring system.(3)

Radiological

Using Alvarado score 7 as cutoff value yielded sensitivity of 76.19%, specificity of 59.46%, positive predictive value of 76.19%, negative predictive value of 56.46% with overall accuracy of 70% while Alvarado cutoff 6 had a sensitivity of 87.30, specificity of 48.65, positive predictive value of 74.32, negative predictive value of 69.23% and overall accuracy of 73%.In comparison to other authors, we find out that Alvarado score below 5 has a very high sensitivity to rule out appendicitis up to 99% as described in a meta-analysis published by Ohle, et al., in which 42 studies between January 1986 and April 2011 were enrolled and studied.(12) In contrary in the same meta-analysis they showed a sensitivity of 82 % and specificity of 81 % on using Alvarado score 7 as cutoff for diagnosing appendicitis which is higher than our current study results.(12)In a study published by Tade; sensitivity was 100% as scores below 5 and specificity of 100% at Alvarado score

Ultrasound in our study has an overall sensitivity of 73.02%, specificity of 100%, positive predictive value of 100%, negative predictive value of 68.52% and overall accuracy of 83%.In a study carried out by Nasiri, et al., ultrasound had 71.2% sensitivity, 83.3%specificityand 72.4% accuracy(1), while in the study carried out by Gokce, et al., showed sensitivity of 69%, specificity of 60%and accuracy of 67%.(9)Khanal, et al.,in his study had a sensitivity of 85.7% and specificity of 100%, positive predictive value of 100%, negative predictive value of 6.7% and accuracy of 85.9% for ultrasound.(17)Gracey, et al., in their 3 year study documented an overall sensitivity of 93.8% and specificity of