RESUMO
OBJECTIVE: Little is known about the positive predictive value of diagnostic tools for severe acute appendicitis (AA). Our objective was to study a retrospective cohort of patients with AA, emphasizing its laboratory and radiologic features, to establish risk factors for more severe cases of AA. METHODS: A retrospective cohort study with patients with AA confirmed by biopsy was performed. In each case, examinations were reviewed, data were compared, and laboratory and radiologic findings were established to identify risk factors for severe AA. RESULTS: During the studied period, 405 children, with a mean age of 120 months, were evaluated. Most of the patients were boys (63.2%). C-reactive protein was the best parameter for the diagnosis of perforated AA, with a sensitivity of 88% for values above 173 mg/dL. A total of 64.4% of the patients underwent abdominal ultrasound, and 26% had normal results. CONCLUSIONS: Acute appendicitis is a disease with a wide spectrum of complications; thus, it is important to recognize the markers associated with severe cases of AA. High levels of C-reactive protein were the best markers associated with perforated appendicitis, and ultrasound was requested in most of the cases but was not helpful in most of them.