Alvarado score; validity in diagnosing acute appendicitis

ABSTRACT

To determine the validity of Alvarado score in diagnosing acute appendicitis keeping histopathology of appendix as gold standard. Cross sectional [Validation] study. Department of Surgery Combined Military Hospital Rawalpindi from April 2009 to October 2009. 90 patients with clinical suspicion/diagnosis of acute appendicitis were included in study. All were divided into two groups on the basis of Alvarado score. Group I with score 7-10, who underwent open appendicectomy. Group ll [a] with 5-6, who were observed in hospital. Group ll [b] with< 4 were discharged. In all operated cases appendix was sent for histopathology. Alvarado score was compared with histopathology [gold standard] Male to female ratio was 3.51. Mean age was 25.34. Alvarado score had overall 88.13% sensitivity, 70.96% specificity, 85.24% PPV. 75.86% NPV and 16.90% negative appendicectomy rate. Whereas in male patients it had 90.74% sensitivity, 75% specificity, 92.45% PPV, 70.58%NPV and 6.89% negative appendicectomy rate. In female it had 60% sensitivity, 66.66% specificity, 37.5% PPV, 83.33%NPV and 38.46% negative appendicectomy rate. Alvarado score is very accurate for acute appendicitis in male patients. Patients with score 4 can safely be discharged home. USG should be performed routinely in female patients to improve the diagnostic accuracy of Alvarado score