An outbreak of Pseudomonas aeruginosa infections associated with flexible bronchoscopes.
BACKGROUND
Endoscopes, including bronchoscopes, are the medical devices most frequently associated with outbreaks of nosocomial infections. We investigated an outbreak of Pseudomonas aeruginosa infections after bronchoscopic procedures.


METHODS
Microbiologic results were reviewed to determine the rates of recovery of P. aeruginosa from bronchoalveolar-lavage specimens. Environmental samples from endoscopes and the endoscopy suite were cultured. Medical records were reviewed to identify infections in the 14 days after a bronchoscopy.


RESULTS
The rate of recovery of P. aeruginosa from bronchoalveolar-lavage specimens obtained with use of endoscopy-suite bronchoscopes increased from 10.4 percent at base line to 31.0 percent during the outbreak (relative risk, 2.97; 95 percent confidence interval, 2.28 to 3.90). Cultures of samples from three bronchoscopes grew P. aeruginosa, whereas cultures of samples from the environment, instrument-cleaning machines, and gastrointestinal endoscopes did not. The three bronchoscopes had been part of a nationwide recall. A total of 414 patients underwent bronchoscopy during the outbreak, and there were 48 respiratory tract and bloodstream infections among 39 of these patients (9.4 percent). In 32 infections (66.7 percent), P. aeruginosa was confirmed as a potentially causative organism. Exposure to a potentially contaminated bronchoscope may have had a role in the death of three patients. The rate of recovery of P. aeruginosa returned to base line after the instruments were removed from service.


CONCLUSIONS
This large outbreak of P. aeruginosa infections related to bronchoscopy was apparently caused by a loose biopsy-port cap in the bronchoscopes. Instrument safety and surveillance methods for bronchoscopy must be improved, and better recall procedures are needed for medical devices.
Srinivasan
Arjun
A
Department of Hospital Epidemiology and Infection Control, Johns Hopkins Medical Institutions, Baltimore, Md, USA.
Wolfenden
Linda L
LL
Song
Xiaoyan
X
Mackie
Karen
K
Hartsell
Theresa L
TL
Jones
Heather D
HD
Diette
Gregory B
GB
Orens
Jonathan B
JB
Yung
Rex C
RC
Ross
Tracy L
TL
Merz
William
W
Scheel
Paul J
PJ
Haponik
Edward F
EF
Perl
Trish M
TM
D000046:Academic Medical Centers; D015142:Baltimore; D020680:Bronchoscopes / Q000382:microbiology*; D004196:Disease Outbreaks; D004866:Equipment Contamination; D004867:Equipment Design; D004868:Equipment Failure; D006746:Hospital Bed Capacity, 500 and over; D006801:Humans; D011552:Pseudomonas Infections / Q000209:etiology*; D011550:Pseudomonas aeruginosa / Q000145:classification / Q000302:isolation & purification*