[Gangrenous and perforating appendicitis in a provincial hospital: a 48-month retrospective study. Clinical and microbiological aspects, course and postoperative morbidity].

The appendectomy for gangrenous or perforated appendicitis is made more serious by a very high frequency of infection. The antibiotic prophylaxis should be able to reduce the frequency of such complications. We have considered retrospectively the patients who underwent appendectomy for gangrenous and perforated appendicitis in the period from June 1st, 1986 to May 31st 1990 in the Ivrea-Castellamonte hospital (Province of Turin), focusing our attention on certain microbiological and clinical variables in relation to the post-operative course. The average age of the 43 patients admitted to the study, 25 male adults and children and 18 female adults and children, was 27.4; the pediatric number totalled 22 subjects of which 14 male; the group of 21 adults included 11 males. 7 adults presented concomitant pathologies. The average stay in bed was 10.7 days (12.9 for the adults--8.6 for the children); 61.9% of the adults had a stay of more than 10 days, 72.7% of the children less than 10 days (P less than 0.05). The incidence of the infective complications in the whole group was 25.6% (33.3% of adults against 18.2% of children); infection of surgical wounds was observed in 18.6% of the cases (28.6% of the adults against 9% of children). The pre-operative antibiotic prophylaxis was activated in 22 patients (11 adults, 11 children) and the antimicrobic treatment was continued in the post-operative phase for an average of 7.3 days in the case of the adults and 5.9 days in the case of the children. Of the 21 patients not subjected to prophylaxis (10 adults, 11 children) all received post-operative antibiotic therapy (an average of 8 days for the adults, 7.8 days for the children). The incidence of septic complications in the group subjected to antibiotic prophylaxis was 18.2% as against 33.3% of the group not subjected; the incidence of infection of the wound being 13.6% against 23.8%. The per-operative cultures of pus coming from the peritoneum cavity were positive in 83.7% of the cases (53.5% mixed aerobe-anaerobe cultures). The microorganism most frequently isolated were: Escherichia coli (27.7%), Bacteroides fragilis (7.9%), other Bacteroides spp. (20.8%), among the positive gram aerobes the Streptococcus milleri (6.9%) prevails; the most common association is the between Bacteroides spp. and Enterobacteria (19 cases); in a good 17 cases the enterobacteriaceae is represented by the Escherichia coli; the Bacteroides, E. coli and Streptococcus association is, however, observed in 10 cases. Our study confirms the usefulness of the peri-operative antibiotic prophylaxis in the cases of a gangrenous or perforated appendicitis.