Hepatic abscess: changes in clinical, bacteriologic and therapeutic aspects

Clinical, bacteriologic and therapeutic aspects of 53 patients with hepatic abscess seen from 1961 to 1973 are reviewed. Of these abscesses, 50 were pyogenic and 3 amebic in etiology. The mortality was 63 per cent; the greatest number of cases (38) and the greatest mortality (79 per cent) occurred in patients over 50 years of age. Thirty-five patients had macroscopic abscesses; in the remaining 18 the abscesses were microscopic in size. The most common causes of pyogenic macroscopic abscess were biliary tract infection (11 cases), direct extension from contiguous sites of infection (8 cases) and nonpenetrating trauma (5 cases). The causes of microscopic abscesses were biliary tract infection (9 cases), systemic bacteremia (8 cases) and pylephlebitis (1 case). Although the diagnosis was often obscure with nonspecific clinical and laboratory findings, the hepatic scintiscan and abdominal angiography were positive in all cases in which the abscesses were greater than 1 cm in diameter. Bacteria of bowel origin (particularly Escherichia coli, other Enterobacteriaceae and anaerobes) were the common etiologic agents. Staphylococcus aureus was implicated predominantly in children with bacteremia. Prolonged antibiotic administration and aggressive surgical drainage are the cornerstones of effective therapy.