Acquired outside the healthcare setting
More than 48 hours after admission, recent hospitalization, dialysis, or resident of long term care facility
Late onset (more than 5 days after admission) is associated with more resistant microorganisms
Localized to single organ without perforation
Extending into the peritoneal space, with peritonitis
Antibiotic therapy in preceeding 90 days or immune-compromised
Modality depends on the clinical diagnosis
If a perforated viscus is suspected, plain X-ray (supine, upright, and lateral decubitus) should be done to look for free air
Ultrasound or CT is usually required to diagnose or characterize organ infections (e.g. cholecystitis, cholangitis, liver abscess) and abscesses
Source control is necessary; if symptoms present for a few days, can delay antibiotics if stable and pending source control procedure/specimen collection
Lack of clinical improvement should prompt further source control, rather than prolonging or changing antimicrobial therapy in the absence of culture results to support a change in antimicrobial management
Antibiotic recommendations below are empiric; tailor antibiotics to microbiology results