title: Serological cross-reactions between Coxiella burnetii and Legionella micdadei.
abstract: Coxiella burnetii and Legionella micdadei are both gram-negative bacteria potentially responsible for identical clinical syndromes resembling upper respiratory infections. These infections, quite common in immunocompromised patients, are usually diagnosed by serology with a microimmunofluorescence assay. We found that 34.5% of Q fever patients had a significant titer of antibodies against L. micdadei. Cross-reactions involved immunoglobulin G antibodies and were demonstrated by a cross-adsorption study and protein immunoblotting. Western blot analysis performed after treatment with proteinase K indicated that cross-reactions were probably due to both protein and lipopolysaccharide antigens. It is critical that the existence of this cross-reaction be recognized, as misdiagnosis of either condition may lead to incorrect and ineffective treatment.
authors.affiliation: Unité des Rickettsies, Faculté de Médecine, CNRS EP J 0054, Marseille, France.
authors.forename: D
authors.initials: D
authors.lastname: Musso
authors.forename: D
authors.initials: D
authors.lastname: Raoult
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood; D001782:Blood Donors; D016997:Coxiella burnetii / Q000276:immunology*; D003429:Cross Reactions; D005602:France / Q000453:epidemiology; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D007875:Legionella / Q000276:immunology*; D007876:Legionellosis / Q000453:epidemiology / Q000276:immunology; D011778:Q Fever / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M