RT Journal Article
SR Electronic
T1 Hypersensitivity pneumonitis and metalworking fluids contaminated by mycobacteria
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP 640
OP 647
DO 10.1183/09031936.00195009
VO 37
IS 3
A1 I. Tillie-Leblond
A1 F. Grenouillet
A1 G. Reboux
A1 S. Roussel
A1 B. Chouraki
A1 C. Lorthois
A1 J-C. Dalphin
A1 B. Wallaert
A1 L. Millon
YR 2011
UL http://erj.ersjournals.com/content/37/3/640.abstract
AB Metalworking fluids (MWF) are responsible for hypersensitivity pneumonitis (HP). The aim of the present study was to identify the antigen (Ag) responsible for MWF-associated HP, and to optimise serological diagnosis by definition of a threshold allowing discrimination between HP patients and asymptomatic exposed workers. 13 patients, who were workers at a car engine manufacturing plant, were suspected of MWF-associated HP. Microbial analysis of 83 used MWFs was carried out. Sera from 13 MWF-associated HP patients, 12 asymptomatic exposed workers and 18 healthy unexposed controls were tested to determine their immunological responses to three Ags, including Mycobacterium immunogenum. M. immunogenum was identified in 40% of used fluids by culture and confirmed by DNA sequencing. The threshold for differentiating MWF-associated HP patients from asymptomatic exposed workers was five arcs of precipitation (sensitivity 77% and specificity 92%), as determined by electrosyneresis (ES). Using ELISA methods with protein extract from M. immunogenum, a threshold leading to 92% sensitivity and 100% specificity was established. The detection of specific antibodies against M. immunogenum Ag at high levels in case sera suggests that M. immunogenum-contaminated MWF is responsible for MWF-associated HP. To discriminate MWF-associated HP patients from asymptomatic exposed workers, we suggest a five-arc threshold for ES and a 1.6-AU threshold for ELISA methods.