UTILIDAD DE LA RADIOGRAFÍA SIMPLE DE ABDOMEN PARA EL DIAGNÓSTICO DE APENDICITIS AGUDA EN LA SALA DE URGENCIAS DEL HOSPITAL GENERAL REGIONAL NÚMERO 1 QUERÉTARO

Abstract

OBJECTIVE: To determine the usefulness of plain abdominal radiography for the diagnosis of acute appendicitis by determining the sensitivity and specificity. MATERIAL AND METHODS: A cohort study to a diagnostic test using the sampling technique to share in the emergency department of HGR1 Queretaro in the period from March to December 2010, calculating sample size with the formula for a trial study diagnostic, with confidence level of 95%. Patients older than 17 who were admitted with clinical symptoms compatible with acute appendicitis who underwent plain abdominal radiography and laboratory studies to assess Alvarado score are classified, with surgery between 9 and 10 points correspondent to Group A. Taking into account 3 considered positive radiological signs, entering the Group B who were not positive and Alvarado score of less than 9, using as gold standard histopathology, institutional informed consent, attached to the statements of the 18 Assembly Helsinki WorldMedical. LAST RESULTS: The sensitivity of plain radiography for the diagnosis of appendicitis was 69%, specificity 47%, and radiographic finding most frequent sentinel loop with 64.5%, psoas erased 61.5% and scoliosis Analgesic 58% (134p) in group A. 115 cases were detected true positives and 106 true negatives. En the group B was found more frequently coprostasis in 56% followed by loop guard in 35%, average age 35 years. CONCLUSIONS: The plain abdominal radiograph has low specificity and sensitivity for detecting acute appendicitis, its usefulness lies in finding at least 3 radiological signs suggestive of the disease in 58% of patients with high likelihood of Alvarado score, is affordable and so economically but not justified its use in the emergency room HGR1 Querétaro.