TABLE 2.

International guidelines allowing empirical dual-coverage therapy against Pseudomonas aeruginosa^a

Guideline (reference)	Organization	Yr	Recommendations
Management of adults with hospital-acquired and ventilator-associated pneumonia (9)	IDSA, ATS	2016	For VAP, 2 antibiotics with anti-P. aeruginosa activity are recommended if any of the following are present: (i) a risk factor increasing the likelihood of Gram-negative bacterial infection or antimicrobial resistance, (ii) >10% resistance of Gram-negative bacterial isolates on a hospital unit to an agent being considered for monotherapy, (iii) the lack of availability of local antimicrobial susceptibility rates for the ICU, and (iv) an increase in the risk of Gram-negative bacterial infection because of structural lung disease (i.e., bronchiectasis or cystic fibrosis). For HAP, 2 antibiotics with anti-P. aeruginosa activity are recommended if any of the following are present: (i) risk factors increasing the likelihood for P. aeruginosa or other Gram-negative bacterial infection, and (ii) patients are at high risk for mortality (e.g., need for ventilator support and septic shock).
Guidelines for the management of adult lower respiratory tract infections (10)	ESCMID, ERS	2011	The use of 2 antibiotics with anti-P. aeruginosa activity is recommended for CAP patients requiring ICU or immediate care when risk factors for P. aeruginosa infection are present.
Use of antimicrobial agents in neutropenic patients with cancer (11)	IDSA	2010	Additional antibiotics with anti-P. aeruginosa activity may be added for management of complications (e.g., hypotension and pneumonia) or if antimicrobial resistance is suspected or proven.
Prevention and treatment of cancer-related infections (12)	NCCN	2017	Initial combination therapy should be considered for febrile patients at high risk for P. aeruginosa infections. Combination therapy may also be considered in complicated or resistant cases.
European guidelines for empirical antibacterial therapy for febrile neutropenic patients (13)	ECIL	2013	A deescalation treatment approach with the empirical use of 2 antibiotics with anti-P. aeruginosa activity may be considered if one of the following criteria are present: (i) known prior colonization or infection with resistant pathogens, (ii) complicated presentation (e.g., severe sepsis, septic shock), (iii) high rates of resistant nonfermenters on the basis of local epidemiology, or (iv) carbapenem use within the past month.
Diagnosis and management of prosthetic joint infection (14)	IDSA	2013	The use of 2 antibiotics with anti-P. aeruginosa activity may be considered on the basis of the clinical circumstances of the patient.
Clinical practice guidelines for the diagnosis and treatment of native vertebral osteomyelitis in adults (15)	IDSA	2015	The use of 2 antibiotics with anti-P. aeruginosa activity may be considered.
International guidelines for management of sepsis and septic shock (16)	SSC	2016	Supplemental use of an agent with activity against Gram-negative bacteria is recommended for critically ill septic patients at high risk of infection with multidrug-resistant pathogens (including P. aeruginosa).
Combination antibiotic therapy for empirical and definitive treatment of Gram-negative bacterial infections (17)	SIDP	2011	The use of 2 antibiotics with anti-P. aeruginosa activity is reasonable for empirical treatment of suspected health care-associated infections, particularly when risk factors for multidrug-resistant organisms are present.

^aDefinitions: ATS, American Thoracic Society; CAP, community-acquired pneumonia; ECIL, European Conference on Infections in Leukemia; ERS, European Respiratory Society; ESCMID, European Society of Clinical Microbiology and Infectious Diseases; HAP, hospital-acquired pneumonia; ICU, intensive care unit; IDSA, Infectious Diseases Society of America; NCCN, National Comprehensive Cancer Network; SIDP, Society of Infectious Diseases Pharmacists; SSC, Surviving Sepsis Campaign; VAP, ventilator-associated pneumonia.