Heterophile antibodies produce spuriously elevated concentrations of cardiac Troponin I in patients with Legionella pneumophila.
We found an unusually high positive rate for cTnI in patients recently infected with Legionella pneumophila. The aim of this study was to examine the possible origin of increased cTnI levels and to test if it could be associated with the immune response to legionellosis. The cTnI was above the cut point in 46.7% of patients infected with legionellosis when measured with reagent lot number RF421A. A strong correlation between high cTnI measurements and positive serologic values for legionellosis was found. With a revised formulation of cTnI reagent, lot number RF421C, the positive rate decreased by over 10-fold to 3.3%. We conclude that the revised lot of cTnI reagent minimized interference by heterophilic antibodies produced in response to legionellosis.
García-Mancebo
M Lucía
ML
Servicio de Análisis Clínicos, Hospital Universitario Virgen de la Arrixaca, Ctra. Madrid-Cartagena S/N, 30120 El Palmar (Murcia), Spain.
Agulló-Ortuño
M Teresa
MT
Gimeno
Juan R
JR
Navarro-Martínez
M Dolores
MD
Ruíz-Gómez
Joaquín
J
Noguera-Velasco
José A
JA
D000328:Adult; D000368:Aged; D000910:Antibodies, Heterophile / Q000097:blood*; D005260:Female; D006801:Humans; D007118:Immunoassay; D016952:Legionella pneumophila / Q000276:immunology*; D007876:Legionellosis / Q000276:immunology; D008297:Male; D008875:Middle Aged; D019210:Troponin I / Q000097:blood*
D000910:Antibodies, Heterophile; D019210:Troponin I