Over the period of 4 years from 1993 to 1996 the authors recorded a 6% incidence of patients with periappendicular mass (PM) in a group of 786 patients with acute appendicitis. The aim of the study is to compare the two methods in the management of patients (operation – A, conservative treatment – B) by applying the same criteria. In the subacute phase of the disease 22 patients (group A) were operated on, while 24 patients (group B) were successfully treated conservatively, with recommendation of elective appendectomy after 6 months. In group A indication for operation was PM in 7 patients, diagnostic problems (tumour, hydronephrosis) or complications (peritonitis, intestinal obstruction) in 15 patients. Antibiotic therapy was nearly the same in both group. Peritoneal drainage in postoperative care was performed in 10 patients of group A for 4.7 days on the average. In this group, secondary wound healing was recorded in 3 patients. In group B, elective appendectomy was performed only in 12 patients (50 %). In 2 patients, however, a diagnostic error was revealed, i.e. Crohn’s disease and an ovarian cyst had been suspected to be a periappendicular mass. Conservative treatment with subsequent elective appendectomy after 6 months seems to be an effective method in the treatment of patients with a typical clinical picture and well bordered periappendicular mass. Appendectomy in the subacute phase of the disease appears to be a safety technique of PM treatment in patients with complications or diagnostic problems.

        Key words: appendicitis – periappendicular mass – subacute appendicitis – appendectomy