Legionella prevention nosocomial patients "at risk": towards zero risk?

Mr. Reyrolle, S. Guards, S. Coudrais, J. Droguet, G. Lina, R. Girard, S. Jarraud


Prevention of nosocomial Legionnaires cases remains a public health concern because mortality can exceed 20% for immunocompromised patients. When water is colonized a hospital when it opens the risk can be significant as was the case in 2001 at the George Pompidou European Hospital. The construction of a new building in a hospital requires a multidisciplinary reflection and implementation of preventing bacterial colonization measures of water systems from the building design. The law theoretically allows to manage risk as it requires noL.pneumophila in patients at high risk services (HR) (2). No regulations exist for L pneumophila non- water hospitals.

Objective: The aim of this work was to prevent the risk of bacterial colonization with Legionella for a new building of Hematology 42 rooms at Centre Hospitalier Lyon.

Methods: The building was built with the Waterclean system (CIAT). CATREL the procedure of carrying out purges and monitoring of bacterial colonization from impoundment was applied (1). For analytical monitoring of cold water (EF) and hot water (DHW) the Legionella were quantified by crop (NFT 90-431) and by PCR (NFT 90-471), the total flora 22 ° C to 37 ° C and the presence of Pseudomonas aeruginosa (ISO 16266) were analyzed. Monthly or bi-monthly analyzes were implemented on 12 points from impoundment in December 2010 until the arrival of patients in September 2011. After the arrival of patients, monitoring continued. The diagnosis of legionellosis for patients is achieved by detection of urinary antigen (Now Legionella ), culture and PCR for respiratory samples.


The environment: the bacterial flora was present for Legionella by culture, no Lp was détectéesauf rare Lanisa , PCR results were 10 3 2x10 4 UG / L L. spp and L. pneumophila.

The cases of legionellosis: in March 2012 was diagnosed by PCR and sequencing L anise on a lung sample. The patient also had a co-infection with H1N1et aspergillus , he died.

Following the event, showers and faucets of the 42 rooms have been secured with terminal filters. Daily purges were implemented. Analytical monitoring only PCR Legionella every 15 days is made ​​with the aim of having results PCR L spp Lp <LD.

The installed filters reduce flow and may increase the biofilm, they can be removed if the PCR analysis are consistent with the agreement of the LRA.

Conclusion: The legislation defines absence of L pneumophila in water systems for HR patients, but this study shows that L anisa is pathogenic even if only the presence of DNA is detected. For services with HR patients, regular monitoring of the RU and the ECS in PCR with LSPP and Lp thresholds should help manage risk.


Full conference title: 

Réunion Interdisciplinaire de Chimiothérapie Anti Infectieuse
    • RICAI 32nd (2012)