[Appendiceal diverticulitis: A possible diagnosis in acute abdomen].

Diverticulosis of the appendix is an uncommon disease with an incidence in appendectomy specimens that ranges between 0.004% and 2.1%. Diverticula may cause the inflammatory process, although occasionally they are findings that are not directly related with the acute appendiceal symptoms. Symptoms of appendiceal diverticulitis are difficult to distinguish from acute appendicitis. It is usually diagnosed as an incidental finding in the surgical specimens from interventions due to acute abdomen and associated with the finding of appendicitis. We present a case of diverticulosis in a 54-year-old woman who complained of abdominal pain over the course of the previous 3 days, which was initially located in the right iliac fossa (RIF) and accompanied by fever. Examination detected abdominal pain and guarding in the RIF with positive Blumberg sign. No acute phase reactants were observed in the blood sample. Abdominal ultrasound of the RIF showed a tubular structure with a sac-like end measuring 8 mm in thickness, with an adjacent hypoechoic area and increased echogenicity of the adjacent mesentery with a small formation of free fluid (Fig. 1). With the diagnosis of an acute appendiceal condition, we operated by means of a McBurney incision and observed the cecal appendix with diverticula along its entire length. Those that were situated at the more distal end presented signs of inflammation, with important mesenteric thickening. Appendectomy was performed. The postoperative recovery was uneventful and the patient was discharged on the third postoperative day. The pathology study of the specimen reported diverticulosis of the vermiform appendix, accompanied by mucocele and abscesses rich in eosinophils. No appendicular parasites were identified (Fig. 2). The presence of diverticula in the cecal appendix was described for the first time by Kelynak in 1893. The appearance of diverticulosis of the appendix is exceptional, with a mean incidence of around 1%. Diagnosis is usually incidental, generally during the pathology study of the appendix. Appendiceal diverticulitis is an inflammatory clinicopathological disease that is different from acute appendicitis; it is more common in men around the fifth decade of life and presents a higher mortality rate. Morphologically, there are 2 main subtypes of diverticula: true and false. True or congenital diverticula are caused by abnormal intestinal permeability in the solid phase. Meanwhile, pseudodiverticula, false diverticula or acquired diverticula (mean incidence 1%) are caused by increased pressure on the least resistant points of the c i r e s p . 2 0 1 5 ; 9 3 ( 6 ) : e 4 9 – e 5 1