Intra-abdominal Infections

Question 1

Antimicrobials for acute pancreatitis

Answer 1

General – Antibiotics are NOT recommended. c. Pancreatic necrosis confirmed by computed tomography (CT) scan and suspected to be infected (sterile necrosis does NOT require antibiotics) v. Some experts suggest that more than 50% threshold of necrotic tissue should be used. vi. Initiation in those who deteriorate after 7–10 days of hospitalization: CT-guided fine needle aspiration for culture is recommended to guide therapy.

Antibiotic management recommendations a. Antipseudomonal β-lactam including piperacillin/tazobactam, meropenem, imipenem/cilastatin; cefepime plus metronidazole

Therapy duration recommendations: 10–14 days (most randomized controlled trials used 14 days); may be dictated by additional sequelae e. Antibiotic therapy in patients with infected necrosis may reduce mortality compared with surgery alone (50% reduction) or potentially reduce the need for subsequent surgical intervention in stable patients (e.g., conservative antibiotic management)

Question 2

Antibiotics for acute appendicitis

Answer 2

Rupture risk is less than 2% if managed within 36 hours of beginning of symptoms; 12-hour delay beyond increases risk of rupture to 5% or greater. Less than 6% of patients will have bacteremia
6. Management a. Surgical intervention (with or without antibiotics) versus conservative antibiotic management i. Antibiotic therapy with a suspected rupture is typically a 4-day course,

Appendicitis Acuta (APPAC) trial published in 2015 challenged the surgical paradigm.
Randomized controlled trial of open appendectomy (n=273) versus antibiotic therapy alone (n=257) with ertapenem 1 g x 3 days, followed by levofloxacin plus metronidazole x 7 days
Noninferiority was not met; however, the results are examined as follows:
(a) 27.3% of patients in the antibiotic arm required surgery at 1 year (thus, 72.7% did not
require further surgery at 1 year).

Question 3

Diagnosis of peritoneal dialysis-related peritonitis

Answer 3

PD fluid with >100 cells/mm3 with neutrophil predominance

Question 4

Empiric antibiotics for PD-related peritonitis

Answer 4

IP-administered cefazolin or vanco plus (aminoglycoside or cefepime)

Question 5

STOP-IT trial design

Answer 5

Patients with complicated intra-abdominal infection with source control randomized to:
Abx until 2 days after resolution of F/WBC/ileus (up to 10 days)
4 +/- calendar days

Primary outcome: composite of SSI, IAI, death

Question 6

STOP-IT trial results

Answer 6

Primary outcome similar between groups, median duration 4 vs 8 days