VALIDITY OF MODIFIED ALVARADO SCORING SYSTEM (MASS) IN THE DIAGNOSIS OF ACUTE APPENDICITIS

Validity of Modified Alvarado Scoring System

Abstract

Objective: To determine the validity of Modified Alvarado Scoring System (MASS) in the diagnosis of acute
appendicitis.
Study Design: Cross sectional validation study.
Place and Duration of Study: Department of Surgery Combined Military Hospital (CMH) Kohat Pakistan, from Nov 2013 to Oct 2014.
Material and Methods: A total of 248 patients fulfilling the inclusion criteria were enrolled in the study after
getting the informed written consent. Modified Alvarado Score of all patients was calculated on a proforma
which included migratory right iliac fossa pain, anorexia, nausea/vomiting, tenderness in right iliac fossa,
rebound tenderness, elevated temperature and leucocytosis (>10 x 109/L). Surgeries were performed by residents and consultant surgeons. Decision to operate upon was not only on the MASS of the patients rather it was on overall clinical condition of the patients using different scoring systems. Where required aid of different laboratory investigations, ultrasonography, CT scan and laparoscopy was also taken. After surgery histopathological examination of resected specimens was performed. Pre operative modified alvarado score and post operative histopathological results were endorsed on a proforma. A two by two table was used to determine the sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of MASS.
Results: Out of total 248 patients, 183 (73.8%) patients were males and 65 (26.2%) were females. Male to female ratio was 2.8:1. Sensitivity of MASS in this study was 89.39%, Specificity 84.06%, positive predictive value 93.57%, negative predictive value 75.32% and diagnostic accuracy was 87.90%.
Conclusion: Modified alvarado score is a highly sensitive test with fair degree of specificity for the early diagnosis of acute appendicitis especially in the adults. It is particularly helpful for young doctors and in the peripheral hospitals where more sophisticated investigations are not available.