Subphrenic abscess. The new epidemiology.

Recent changes in the etiology, topography, and bacteriology of subphrenic abscess are identified in 93 patients treated between 1955 and 1975. Gastric and biliary tract operation account for 52% of abscesses. Appendicitis is now responsible for only 8% of subphrenic infections, in contrast with the 40% of previous reports. Colonic surgery (19%) and trauma (8%) are increasing in importance. Left-sided abscesses occur in 40%, and multiple space abscesses in 20% of patients. The bacterial flora consists of multiple strains of aerobic and anaerobic organisms. Since 1970, the aerobes have been Escherichia coli (96%), Klebsiella (21%), and Proteus (38%); anaerobes include Bacteroides (83%), cocci (50%), and clostridia (50%). The mean interval from the preceding operation until drainage of the subphrenic abscess was 5.5 weeks. Overall mortality was 31%, with higher mortalities for multiple space involvement (39%) and for abscesses developing after emergency procedures (35%). Recommendations based on this data are: (1) antibiotics selected should be effective against anaerobes, and (2) transperitoneal drainage is frequently indicated because of the increase in multiple abscesses and the need to evaluate the first operation.