An Outbreak of Burkholderia (Formerly Pseudomonas) cepacia Respiratory Tract Colonization and Infection Associated with Nebulized Albuterol Therapy

15 May 1995 | Volume 122 Issue 10 | Pages 762-766

Objective: To investigate an outbreak of Burkholderia (formerly (Pseudomonas) cepacia respiratory tract colonization and infection in mechanically ventilated patients.

Design: A retrospective case–control and bacteriologic study.

Setting: Veterans Affairs medical center.

Patients: 42 mechanically ventilated patients who developed respiratory tract colonization or infection with B. cepacia and 135 ventilator-dependent controls who were not colonized and did not develop infections.

Measurements: Clinical and demographic data; benzalkonium chloride concentrations and pH levels in albuterol sulfate solutions; repetitive-element polymerase chain reaction (PCR)-mediated molecular fingerprinting on eight patient isolates and three environmental B. cepacia isolates that were available for study.

Results: 42 patients had B. cepacia respiratory tract colonization or infection. Observation of intensive care unit and respiratory care personnel showed faulty infection control procedures (for example, the same multiple-dose bottle of albuterol was used for many mechanically ventilated patients). More case patients (39 [92.9%]) than controls (95 [70.4%]; P = 0.006) received nebulized albuterol, and case patients (67.5 treatments) received more treatments than controls (18 treatments; P < 0.001). In-use albuterol solutions had pH values that were unstable, and benzalkonium chloride concentrations declined over time to levels capable of supporting bacterial growth. Medication nebulizers and in-use bottles of albuterol harbored B. cepacia. Molecular fingerprints of patient isolates and environmental B. cepacia isolates were identical using repetitive-element PCR. No further isolates of B. cepacia were identified after institution of appropriate infection control procedures.

Conclusions: Multiple-dose medications and reliance on benzalkonium chloride as a medication preservative provide a mechanism for nosocomial spread of microorganisms, particularly if infection control procedures are not carefully followed. Repetitive-element PCR is a useful fingerprinting technique for molecular epidemiologic studies of B. cepacia.

Author and Article Information

From the Veterans Affairs Medical Center, Baylor College of Medicine, and Texas Southern University, Houston, Texas.
Requests for Reprints: Richard J. Hamill, MD, Section of Infectious Diseases (111G), Veterans Affairs Medical Center, 2002 Holcombe Boulevard, Houston, TX 77030.
Acknowledgments: The authors thank Ann M. Doggett BS, ASCP, David Y. Graham, MD, and Loretta Carson, MS, for provision of bacterial strains; the employees of the Respiratory Therapy Department at the Houston Veterans Affairs Medical Center for their cooperation during this investigation; and Daniel M. Musher, MD, for his review of the manuscript.
Grant Support: By funds provided by the Department of Veterans Affairs.