[Predictive factors of gangrenous post-appendectomy intra-abdominal abscess. A case-control study]

Acute appendicitis is the most frequent surgical urgency in children. Frequently, it can be complicated with an intraabdominal abscess that will require a longer and expensive treatment. Our aim is to know if it is possible to predict this complication before its beginning.

Retrospective case-control study with patients treated between 2011 and 2016, paired according to their own characteristics (age, sex and weight), clinical aspects (symptoms, time of their onset, physical examination) and type of appendicitis (gangrenous). The main variable was the appearance of an intraabdominal abscess in the postoperative period (cases). Univariate and multivariate analysis were performed, with a statistical significance level of p < 0.05.

We included 54 cases and 108 controls. The occurrence of intraabdominal abscess was significantly associated with preoperative hyponatremia (p < 0.001), elevated CRP (p < 0.05), appendix perforation (p < 0.001) and wound infection (p < 0.001). The multivariate analysis dismissed the value of the CRP as an abscess predictor but showed association in the other three variables cited before. There was no association with the presence of generalized peritonitis at the intervention or the type of surgical approach.

Appendix perforation, infection of the surgical wound and hyponatremia at diagnosis are predictive factors for the appearance of a postoperative intraabdominal abscess after acute gangrene appendicitis. We believe that early identification would favor the secondary prevention of this complication and the decrease of its morbidity.