Prospective evaluation of RT-PCR on sputum versus culture, urinary antigens and serology for Legionnaire's disease diagnosis.
Legionnaires' disease (LD) is a severe disease associated with community and hospital-acquired pneumonia, frequently under diagnosed. The main aim of our study was to determine the value of PCR for the diagnosis of LD in routine clinical practice.



In a prospective study, from March 2007 to April 2010, the value of PCR on non-invasive respiratory specimens (NIRS) was compared to those of the other available tools for LD diagnosis in patients hospitalized for pneumonia.



Among 254 consecutive cases of pneumonia included, 24 cases were LD (19 confirmed and 5 probable) representing the first documented microbiological etiology. Molecular diagnosis of LD was performed on NIRS by using 16S rRNA PCR, and secondarily mip PCR, with no discrepant results between the 2 methods: it was found positive in 14 cases and led to identify 2 supplementary probable cases of LD. Based on clinical and at least 2 positive LD tests, PCR yielded a better diagnostic value than antigen urinary test (12 vs 10 cases).



These results revealed that molecular diagnosis of LD on NIRS is reliable and may contribute to better identify cases of LD.
GIMAP EA 3064 (Groupe Immunité des Muqueuses et Agents Pathogènes), COMUE of Lyon, 42023 Saint-Etienne, France; Infectious Diseases Department, University Hospital of Saint-Etienne, 42055 Saint-Etienne Cedex 02, France.
Elisabeth
E
Botelho-Nevers
GIMAP EA 3064 (Groupe Immunité des Muqueuses et Agents Pathogènes), COMUE of Lyon, 42023 Saint-Etienne, France; Laboratory of Infectious Agents and Hygiene, University Hospital of Saint-Etienne, 42055 Saint-Etienne Cedex 02, France.
Florence
F
Grattard
Emergency Unit, University Hospital of Saint-Etienne, 42055 Saint-Etienne Cedex 02, France.
Alain
A
Viallon
GIMAP EA 3064 (Groupe Immunité des Muqueuses et Agents Pathogènes), COMUE of Lyon, 42023 Saint-Etienne, France.
Séverine
S
Allegra
Reference National Centre for Legionella, Centre de Biologie et Pathologie Est, Hospices Civils de Lyon, Lyon, France.
Sophie
S
Jarraud
GIMAP EA 3064 (Groupe Immunité des Muqueuses et Agents Pathogènes), COMUE of Lyon, 42023 Saint-Etienne, France; Laboratory of Infectious Agents and Hygiene, University Hospital of Saint-Etienne, 42055 Saint-Etienne Cedex 02, France.
Paul
P
Verhoeven
Emergency Unit, University Hospital of Saint-Etienne, 42055 Saint-Etienne Cedex 02, France.
Adrien
A
Marcuccilli
GIMAP EA 3064 (Groupe Immunité des Muqueuses et Agents Pathogènes), COMUE of Lyon, 42023 Saint-Etienne, France; Infectious Diseases Department, University Hospital of Saint-Etienne, 42055 Saint-Etienne Cedex 02, France.
Fréderic
F
Lucht
GIMAP EA 3064 (Groupe Immunité des Muqueuses et Agents Pathogènes), COMUE of Lyon, 42023 Saint-Etienne, France; Laboratory of Infectious Agents and Hygiene, University Hospital of Saint-Etienne, 42055 Saint-Etienne Cedex 02, France.
Bruno
B
Pozzetto
GIMAP EA 3064 (Groupe Immunité des Muqueuses et Agents Pathogènes), COMUE of Lyon, 42023 Saint-Etienne, France; Infectious Diseases Department, University Hospital of Saint-Etienne, 42055 Saint-Etienne Cedex 02, France; Laboratory of Infectious Agents and Hygiene, University Hospital of Saint-Etienne, 42055 Saint-Etienne Cedex 02, France. Electronic address: philippe.berthelot@chu-st-etienne.fr.
Philippe
P
Berthelot
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000942:Antigens, Bacterial / Q000652:urine*; D001431:Bacteriological Techniques; D005260:Female; D006801:Humans; D007159:Immunologic Tests; D016952:Legionella pneumophila / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D007877:Legionnaires' Disease / Q000175:diagnosis* / Q000382:microbiology; D008297:Male; D008875:Middle Aged; D025202:Molecular Diagnostic Techniques; D011446:Prospective Studies; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*; D013183:Sputum / Q000382:microbiology*
D000942:Antigens, Bacterial; D012336:RNA, Ribosomal, 16S
Bacteriological methods; Diagnosis; Legionella pneumophila; Legionellosis; Legionnaires' disease; PCR; Pneumonia