Do you clean or contaminate your bronchoscope?

Nosocomial transmission of imipenem-resistant Pseudomonas aeruginosa following bronchoscopy associated with improper connection to the Steris System 1 processor

OBJECTIVE

To assess nosocomial transmission of imipenem-resistant Pseudomonas aeruginosa (IRPA) following bronchoscopy during August through October 1998.

DESIGN

Traditional and molecular epidemiological investigation of a case series.

SETTING

University-affiliated community hospital.

PATIENTS

18 patients with IRPA bronchial-wash isolates.

INTERVENTIONS

We reviewed clinical data, performed environmental cultures and molecular analysis of all IRPA isolates, and observed disinfection of bronchoscopes.

RESULTS

Of 18 patients who had IRPA isolated from bronchoscopic or postbronchoscopic specimens, 13 underwent bronchoscopy for possible malignancy or undiagnosed pulmonary infiltrates. Following bronchoscopy, 3 patients continued to have IRPA isolated from sputum and demonstrated clinical evidence of infection requiring specific antimicrobial therapy. The remaining 15 patients had no further IRPA isolated and remained clinically well 3 months following bronchoscopy. Pulsed-field gel electrophoresis revealed that all strains except one were >95% related. STERIS SYSTEM 1 had been implemented in July 1998 as an automatic endoscope reprocessor (AER) for all endoscopes and bronchoscopes. Inspection of bronchoscope sterilization cycles revealed incorrect connectors joining the bronchoscope suction channel to the STERIS SYSTEM 1 processor, obstructing peracetic acid flow through the bronchoscope lumen. No malfunction warning was received, and spore strips remained negative.

CONCLUSIONS

The similarity of diverse connectors and limited training by the manufacturer regarding AER for bronchoscopes were the two factors responsible for the outbreak. Appropriate connections were implemented, and there was no further bronchoscope contamination. We suggest active surveillance of all bronchoscopy specimen cultures, standardization of connectors of various scopes and automated processors, and systematic education of staff by manufacturers with periodic on-site observation.

Infection control in the bronchoscopy suite. A review

Bronchoscopy can occasionally transmit disease. Infection control in the bronchoscopy suite is especially important because of the risk of transmitting HIV or tuberculosis. Many case reports, patient series, and small studies have been published, but little comprehensive guidance is available for clinicians who wish to learn more about the problem and prevent it. We review the literature and describe three ways in which bronchoscopy can cause disease: by transmitting infections between patients, by transferring microorganisms within a patient, and by triggering coughing that can cause airborne infection of patients or health-care workers. Recommendations for infection control are listed; they include installing powerful air filters, using disposable bronchoscope suction valves, manually cleaning all equipment before disinfection, controlling patient coughing, and in some cases, giving patients prophylactic antibiotics.

Molecular markers for the investigation of Mycobacterium gordonae epidemics

Mycobacterium gordonae was isolated as a light growth from bronchoalveolar aspirates from nine patients over 12 months. All patients were in one hospital, and had been bronchoscoped for suspected malignancy. None of the patients had symptoms or radiographic findings of mycobacterial infection. The isolates were characterized by biochemical tests and molecular hybridization. Random amplified polymorphic DNA analysis (RAPD) was used to test whether the strains had a common origin. All the isolates generated four to eight fragments, and almost all presented distinct RAPD patterns. Antimicrobial resistance patterns to six agents confirmed that the isolates were unrelated. Thus epidemiologically unrelated strains of M. gordonae can exist as contaminants in the same department over a relatively short time frame. RAPD analysis is easy to perform, gives rapid results, and can be used for epidemiological analysis of M. gordonae isolates.