Usefulness of à la carte antigens for bird fancier’s lung serodiagnosis: total dropping extract and/or dropping’s microflora antigens

Abstract

Bird fancier's lung (BFL) is a pulmonary disease caused by inhalation of avian proteins. The involvement of the microorganisms of droppings has been assumed in the past and this idea still persists today. Our study aimed to compare by immunoprecipitation assay the detection of antibodies against both droppings and microorganisms in the sera of patients (n=15) and asymptomatic exposed controls (n=18). We found that 14/15 BFL patients had negative serological results for isolated microorganisms of the droppings, only one positive against Enterobacter sakasakii. Serological arguments were in accordance with diagnosis in 87 % of cases by testing à la carte antigens from each bird dropping versus 20 % using the standard antigenic panel. Otherwise, the microorganisms antigens issued from dropping flora were negative in 93 % of cases. Consequently, it's preferable to use the total extract from the patient's bird droppings to establish the serodiagnosis of the disease.

Hypersensitivity pneumonitis: A new strategy for serodiagnosis and environmental surveys

“…The technique of electrophoresis that is using six antigens, extracted from micro-organisms isolated in contaminated hay, allowed us to diagnose FLD patients with a positive predictive value of 73% and a negative predictive value of 85% [39]. Similarly for BFL diagnosis, it was shown that serological arguments were in accordance with diagnosis in 87% of cases using antigens from the patient's birds versus 20% using a commercial antigenic panel or "homemade" antigens [60,61]. A recent comparison of dropping extracts from three bird species showed cross reactions between bird species and some highly specific antigens [62].…”

“…A recent comparison of dropping extracts from three bird species showed cross reactions between bird species and some highly specific antigens [62]. For rare bird species, using total extract from the bird's feces is often the most efficient way to diagnose BFL [60]. The crucial factor influencing the performance of serology methods is to test the accurate offending antigens.…”