Infectious Diseases in Critical Care Medicine

can be achieved most simply by avoiding the unnecessary treatment of colonized respiratory
secretions or urine (6,7,10). Other important measures to minimize the evolution of MDR
GNBs is not to use antibiotics in place of abscess drainage or to “cover” surgical drains. Lastly,
all of the efforts to prevent, limit, or eliminate MDR GNB strains will be futile if not combined
with an effective infection control containment program that will limit the spread of these
organisms within the CCU and the institution (1,2,14,25–30).
Clinicians should differentiate colonization from infection before considering empiric
antimicrobial therapy in non-critically ill patients in the CCU. In general, colonization should

Table 1 Antimicrobial Therapy of Susceptible and MDRP. aeruginosa, K. pneumoniae,andA. baumannii

Susceptible strains MDR strains

.P. aeruginosa
Serious systemic infection Meropenem If meropenem susceptible:
Cefepime Meropenem
Cefoperazone If meropenem resistant:
Piperacillinamikacin Doripenem
Colistin
Polymyxin B
CAB only?PO Levofloxacin Fosfomycin
.K. pneumoniae
Serious systemic infection Tigacycline Tigecycline
Levofloxacin Colistin
Moxifloxacin Polymyxin B
3 rdgeneration (except ceftazidime)
Cefepime
Carbapenems
CAB only?PO Levofloxacin Fosfomycin
.A. baumannii
Serious systemic infection Meropenem Sulbactam/ampicillin
Ertapenem Colistin
Polymyxin B
Doripenem
CAB only?PO Fosfomycin Fosfomycin

Abbreviations: CAB, catheter-associated bacteriuria; MDR, multidrug resistant; PO, by mouth.

Table 2 Clinical Significance ofP. aeruginosa, K. pneumoniae,andA. baumannii

Organism Colonization Common Infections in Normal Hosts

Infections in Compromised

Hosts

.P. aeruginosa .Respiratory secretions
(ventilated patients)
.Urine (CAB)

.Nosocomial urosepsis

(following urologic

instrumentation)

.Burns
.Bronchiectasis/cystic
fibrosis (CAP)
.Wounds .NP/VAP .Febrile neutropenia
.Aqueous medications/
irrigant solutions
.K. pneumoniae .Respiratory secretions
(ventilated patients)

.NP/VAP

.CVC infection

.Alcoholics (CAP only)

.Urine (CAB)
.Aqueous medications/
irrigant solutions
.A. baumannii .Respiratory secretions
(ventilated patients)

.NP/VAP (sporadic

outbreaks only)

.NP/VAP (sporadic

outbreaks only)

.Urine (CAB) .CVC infections .CVC infections

.Wounds

.Aqueous medications/

irrigant solutions

Abbreviations: CAB, catheter-associated bacteriuria; CAP, community-acquired pneumonia; CVC, central venous
catheter; NP, nosocomial pneumonia; VAP, ventilator associated pneumonia.

518 Cunha