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CHAPTER SUMMARY FROM THE PHARMACOTHERAPY HANDBOOK
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For the Chapter in the Schwinghammer, Handbook (not Wells Handbook anymore) please go to Chapter 43, Intra-Abdominal Infections.
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KEY CONCEPTS
Most intra-abdominal infections are “secondary” infections that are polymicrobial and are caused by a defect in the gastrointestinal (GI) tract that must be treated by surgical drainage, resection, and/or repair.
Primary peritonitis is generally caused by a single organism (Staphylococcus aureus in patients undergoing chronic ambulatory peritoneal dialysis [CAPD] or Escherichia coli in patients with cirrhosis).
Secondary intra-abdominal infections are usually caused by a mixture of bacteria, including enteric gram-negative bacilli and anaerobes, which enhance the pathogenic potential of the bacteria.
For peritonitis, early and effective IV fluid resuscitation and electrolyte replacement therapy are essential. A common cause of early death is tissue hypoperfusion precipitated by inadequate intravascular volume.
Treatment is generally initiated on a “presumptive” or empirical basis and should be based on the likely pathogen(s), local resistance patterns, and severity of illness.
Antimicrobial regimens for secondary intra-abdominal infections should include coverage for enteric gram-negative bacilli and anaerobes. Antimicrobials that may be used for the treatment of secondary intra-abdominal infections depending on severity of illness and microbiology data include: (a) third-generation cephalosporin (ceftriaxone) with metronidazole, (b) piperacillin–tazobactam, (c) a carbapenem (imipenem, meropenem, doripenem, or ertapenem), or (d) a quinolone (levofloxacin or ciprofloxacin) plus metronidazole or moxifloxacin alone.
Treatment of patients with peritoneal dialysis-associated peritonitis should include an antistaphylococcal antimicrobial such as a first-generation cephalosporin (cefazolin) or vancomycin as well as an agent with significant gram-negative activity such as a third-generation cephalosporin or aminoglycoside; intraperitoneal administration is preferred.
The duration of antimicrobial treatment should be 4 days after achievement of source control for most secondary intra-abdominal infections.
Patients treated for intra-abdominal infections should be assessed for the occurrence of drug-related adverse effects, particularly hypersensitivity reactions (β-lactam antimicrobials), diarrhea (most agents), fungal infections (most agents), and nephrotoxicity (aminoglycosides).
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Preclass Engaged Learning Activity
Find one published article that is a prospective study documenting an antimicrobial stewardship intervention and identify a potential intervention to impact the appropriate use of antimicrobial agents in intra-abdominal infections.
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Intra-abdominal infections are those contained within the peritoneal cavity or retroperitoneal space. The peritoneal cavity extends from the undersurface of the diaphragm to the floor of the pelvis and contains the stomach, small bowel, large bowel, liver, gallbladder, and spleen. The duodenum, pancreas, kidneys, adrenal glands, great vessels (aorta and vena cava), and most mesenteric vascular structures reside in the retroperitoneum. Intra-abdominal infections may be generalized or localized, complicated or uncomplicated, and community or healthcare-associated. Uncomplicated intra-abdominal infections are confined within visceral structures, such as the liver, gallbladder, spleen, pancreas, kidney, or female reproductive organs, while complicated intra-abdominal infections involve anatomical disruption, extend beyond a single organ, and yield peritonitis and/or abscess. Peritonitis is ...