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Contamination of the nebulization systems used in the prophylaxis with amphotericin B nebulized in lung
V Monforte1, A Román, J Gavaldà
1Department of Pneumology, Hospital General Universitari Vall d'Hebron, Universitat Autònoma de Barcelona, Spain. vmonforte@vhebron.net
Abstract:
The contamination of nebulizer may be the origin of respiratory infections. The aim of this study was to determine the incidence of contamination in nebulizers used to nebulize amphotericin B in lung transplant (LT) patients and the relationship with bacterial isolation in sputum culture. A prospective, cross-sectional study was conducted with 41 LT patients who were administered amphotericin B with a jet nebulizer. Samples were taken from the nebulizers (prior to nebulization). Sputum culture was carried out and patients were asked whether or not they followed a cleaning and disinfection protocol (washing and brushing with soap and water followed by subsequent disinfection with the Milton method after each nebulization). Contamination was defined as such when potentially pathogenic bacteria were isolated in the nebulizer. Seventeen of the 41 nebulizers (41.4%) were contaminated. In 7 of the 17 cases (41.1%) contamination was polymicrobial. The most common microorganism was Pseudomonas aeruginosa. Fourteen of the 41 patients (34.1%) presented positive sputum cultures, most common was P aeruginosa. In 10 patients (24.3%) pathogenic bacteria was isolated both in the nebulizer and in the sputum. In four of these patients (9.7%) the species was the same. The cleaning and disinfection protocol was carried out by 16 of the 41 patients (39.0%). In 2 of the 16 patients (12.5%) who were following the protocol the nebulizer was contaminated, compared to 15 of 25 patients (60.0%) whose nebulizer was not contaminated (P < .05). Two of the 16 patients (12.%) who were following the protocol presented positive sputum culture compared to 12 of 25 (48.0%) who did not (P < .05). In conclusion, the contamination of the nebulizing systems is frequent when no strict cleaning and disinfection protocol is followed. Patients who did not follow the protocol presented a greater isolation of pathogenic bacteria in the sputum.
Insights
Nebulizer contamination is common in lung transplant patients, increasing respiratory infection risk. Strict cleaning protocols significantly reduce nebulizer contamination and bacterial growth in sputum cultures.
Area of Science:
- Medical Microbiology
- Infectious Diseases
- Pulmonary Medicine
Background:
- Nebulizer use is common in treating respiratory conditions, particularly in immunocompromised patients like lung transplant recipients.
- Contaminated nebulizers can serve as a reservoir for pathogenic bacteria, potentially leading to healthcare-associated infections.
- Amphotericin B nebulization is used in lung transplant patients, necessitating an understanding of associated risks.
Purpose of the Study:
- To determine the incidence of nebulizer contamination in lung transplant patients receiving amphotericin B.
- To investigate the relationship between nebulizer contamination and bacterial isolation in sputum cultures.
- To assess the effectiveness of cleaning and disinfection protocols in preventing contamination.
Main Methods:
- A prospective, cross-sectional study involving 41 lung transplant patients undergoing amphotericin B nebulization.
- Nebulizer samples were collected pre-nebulization for bacterial culture.
- Sputum cultures were performed, and patients reported adherence to cleaning and disinfection protocols.
Main Results:
- 41.4% of nebulizers showed contamination, with Pseudomonas aeruginosa being the most frequent pathogen.
- 34.1% of patients had positive sputum cultures, predominantly P. aeruginosa.
- Patients not adhering to cleaning protocols had significantly higher rates of nebulizer contamination (60.0%) and positive sputum cultures (48.0%) compared to those who did (12.5% and 12.5%, respectively).
Conclusions:
- Nebulizing systems frequently become contaminated when proper cleaning and disinfection protocols are not followed.
- Adherence to strict cleaning and disinfection significantly reduces nebulizer contamination and the isolation of pathogenic bacteria in sputum.
- Implementing and enforcing rigorous cleaning protocols is crucial for preventing respiratory infections in lung transplant patients using nebulizers.
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