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Antimicrobial approach to intra-abdominal infections in adults

Miriam Baron Barshak, MD
Section Editor
Stephen B Calderwood, MD
Deputy Editor
Allyson Bloom, MD


Infections within the abdominal cavity typically arise because of inflammation or disruption of the gastrointestinal tract. Less commonly, they can arise from the gynecologic or urinary tract. Abdominal infections are usually polymicrobial and result in an intra-abdominal abscess or secondary peritonitis, which may be generalized or localized (phlegmon).

The approach to antimicrobial selection and administration for intra-abdominal infections in adults is discussed here. The general and surgical management of these infections are discussed in detail elsewhere. (See "Management of acute appendicitis in adults" and "Acute colonic diverticulitis: Medical management" and "Acute colonic diverticulitis: Surgical management" and "Acute cholangitis" and "Treatment of acute calculous cholecystitis" and "Acalculous cholecystitis: Clinical manifestations, diagnosis, and management" and "Overview of gastrointestinal tract perforation".)

The approach to management of abscesses within specific intra-abdominal organs (such as the liver or kidney) are also discussed in detail separately. (See "Pyogenic liver abscess" and "Invasive liver abscess syndrome caused by Klebsiella pneumoniae" and "Renal and perinephric abscess" and "Management and complications of tubo-ovarian abscess" and "Posthysterectomy pelvic abscess".)

Spontaneous peritonitis and peritonitis associated with peritoneal dialysis are also discussed elsewhere. (See "Spontaneous bacterial peritonitis in adults: Treatment and prophylaxis" and "Microbiology and therapy of peritonitis in continuous peritoneal dialysis".)


Intra-abdominal infections usually arise after a breach in the normal mucosal defense barrier that allows normal bowel flora to inoculate the abdominal cavity. The precise microbiological spectrum depends on the precise gastrointestinal source (ie, small versus large bowel).

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Literature review current through: Nov 2017. | This topic last updated: Mar 14, 2016.
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