Healthcare-associated Intra-abdominal Infections

Patient Population: Pediatric
Condition Major Pathogens  First-choice Therapy Alternative Therapy Comments

Intra-abdominal infection, healthcare-associated, age > 1 month, and excluding infants with necrotizing enterocolitis 

Includes patients with any of the following risk factors for resistant or opportunistic organisms:  

Hospitalized for at least 48 hours before onset of signs/symptoms of intra-abdominal infection  

Significant medical comorbidities and/or healthcare exposure prior to onset of infection 

Infection developed post-operatively (signs/symptoms were not present prior to surgery) 

Refer to BCH SF Necrotizing Enterocolitis Pathway for NEC treatment recommendations 

If the above criteria do not apply and the patient’s signs/symptoms started prior to hospitalization (community-onset), refer to Appendicitis Clinical Algorithm (BCH OAK and BCH SF shared algorithm) 

Enteric gram- negative bacteria 

Pseudomonas aeruginosa, other resistant gram-negative bacteria 


Piperacillin-tazobactam (Zosyn) 100 mg piperacillin/kg/dose (max 4000 mg piperacillin/dose) IV q6h  

Penicillin allergy with lower risk for allergic reaction

50 mg/kg/dose (max 2000 mg/dose) IV q8h  


10 mg/kg/dose (max 500mg/dose) IV q8h  


Penicillin or cephalosporin allergy with higher risk for allergic reaction

15 mg/kg/dose (max 400 mg/dose)  IV q12h  


10 mg/kg/dose (max 500 mg/dose) IV q8h  

Consider ID consult especially if additional patient risk factors for antibiotic resistant infection, immunocompromised patient, severe manifestations or inadequate response to initial empiric therapy 

If a pathogen is isolated from a normally sterile site, therapy should be modified to treat the identified pathogen, but coverage of enteric gram-negatives and anaerobes should usually be maintained because intra-abdominal infections are usually polymicrobial. Consult ID for further recommendations if needed.  

Duration: If adequate source control, 4 days 

If source control procedure not performed, but favorable response to therapy, 5-7 days guided by clinical parameters (fever, leukocytosis, adequacy of gastrointestinal function)  



Mazuski JE, et al. The Surgical Infection Society revised guidelines on the management of intra-abdominal infection. Surgical Infections 2017;18:1-76. 

Pediatric Empiric Antimicrobial Therapy Guidelines

This is a subsection of the UCSF Benioff Children’s Hospitals Empiric Antimicrobial Therapy Guidelines, developed by the Pediatric Antimicrobial Stewardship Programs at each campus to inform initial selection of empiric antimicrobial therapy for children at the UCSF Benioff Children’s Hospitals and affiliated outpatient sites. 

These are guidelines only and not intended to replace clinical judgment. Modification of therapy may be indicated based on patient comorbidities, previous antibiotic therapy or infection history. Doses provided are usual doses but may require modification based on patient age or comorbid conditions. Refer to Pediatric Antimicrobial Dosing Guideline for further guidance on dosing in children, and Neonatal Dosing Guideline for infants < 1 month of age. Consult a pediatric pharmacist for individualized renal or hepatic dose adjustment. Durations provided are usual recommendations for patients who are responding appropriately to therapy. For additional guidance, please contact Pediatric Infectious Diseases (ID) or the Pediatric Antimicrobial Stewardship Program (ASP) at the campus where your patient is receiving care.  

For questions or feedback about these guidelines, please email primary content owners, Rachel Wattier, Pediatric ASP Medical Director at BCH SF and Prachi Singh, Pediatric ASP Medical Director at BCH OAK. 

The content of these guidelines was updated in July 2021. See Summary and Rationale for Changes (password login to Box needed) for detailed explanations of the content changes.