Evaluación de la Escala de Alvarado versus Score de Respuesta Inflamatoria de la Apendicitis, Hospital José Carrasco Arteaga 2018

BACKGROUND: Acute appendicitis is the main cause of non-traumatic acute abdomen worldwide, it is still a public health issue and the diagnosis can be challenging. When an atypical case is presented, is necessary to use diagnostic scores, like Alvarado Score, Modified Alvarado Score, RIPASA, among others. The aim of this study was to determine the test validity of Inflammatory Response Score versus Alvarado Score, for acute appendicitis diagnosis in 16 year old and older patients. METHODS: This is a descriptive, cross-sectional, validity test study, to compare AIR Score and Alvarado Score, with the Gold-Standard histopathology results. A sample of 292 patients that went under appendectomy at Hospital José Carrasco Arteaga during 2018 was studied. We considered sensitivity, specificity, positive predictive value (PPV), negative predictive value (VPN), ROC curve and Likelihood Ratio. RESULTS: 49.7% patients were young adults, 62.7% of the patients were male. Alvarado Score showed a 88.5% sensitivity, 29.6% specificity, PPV of 81.7%, 42.2% NPV, 1.23 LR+ and 0.38 –LR; compared to 94.7% sensitivity, 76.5% specificity, 93.5% PPV, 80.3% NPV, 4.02 +LR, 0.611 -LR for Appendicitis Immflamatory Response Score. ROC curve for AIRS was 0.897, higher than Alvarado Score (0.611); being AIRS a more precise diagnostic test than Alvarado Score. CONCLUSIÓN: AIRS showed higher sensitivity (94.7%) and specificity (76.5%) than Alvarado Score (88.5%, 29.6% respectively). Alvarado Score is sensitive enough for acute appendicitis diagnosis, but not specific enough to exclude the diagnosis. AIRS shows a higher Likelihood Ratio and ROC curve than Alvarado Score, but the posttest probability is low for identifying acute appendicitis cases.