Detection of salivary and seric IgG and IgA antipooled pigeon sera activities in patients with pigeon breeder's disease

Abstract

Pigeon breeder's disease (PBD) is an interstitial lung disease induced by exposure to pigeon antigens. Search of antipigeon antigen antibodies (APSA) in serum or bronchoalveolar lavage is generally used for auxiliary diagnostic purposes. However, APSA can be present in a number of exposed but asymptomatic individuals as well as in patients with other interstitial lung diseases who live in areas where keeping pigeons is a common domestic habit. In this study, saliva was evaluated as an alternative means to serum for APSA detection by ELISA using pooled pigeon sera as antigen. Serum and saliva samples obtained from 17 patients with PBD, 14 with idiopathic pulmonary fibrosis (IPF), 19 asymptomatic relatives (AR) exposed to pigeon antigens, and 27 clinical healthy voluntary subjects (CHVS) were tested for IgG and IgA APSA. Our results showed that both fluids obtained from PBD patients exhibited a significantly higher specific IgG antibody activity compared to the other groups. Serum optical density (O.D.) values for PBD were 1.187 +/- 0.738 vs. 0.024 +/- 0.033, 0.255 +/- 0.471, and 0.204 +/- 0.346 for CHVS, AR and IPF, respectively (P < 0.05). Salivary O.D. for PBD were 0.801 +/- 0.447 vs 0.010 +/- 0.011, 0.104 +/- 0.151, and 0.22 +/- 0.447 (P < 0.05). In contrast, serum specific IgA did not discriminate between PBD and IPF patients. In addition, although the PBD group exhibited the highest values of IgA salivary APSA, high levels were also observed in saliva specimens from CHVS, a group of normal individuals who deny pigeon exposure. These findings suggest that measurement of IgG salivary APSA can play a role in the evaluation process of patients with pigeon breeder's disease.