Pigeon Breeder's Disease and P Blood Groups

Abstract

To the Editor: In an editorial entitled “P1 Blood Group, Pigeon Antigens, and Respiratory Disease” in the December 1976 issue (Chest 70:694, 1976), I suggested that individuals without the P1 antigen (P2 blood phenotype) may have a greater risk of respiratory disease and that this hypothesis should be tested among individuals selected for respiratory disease, rather than for handling of birds. In their reply to that editorial, Radermecker and Bruwier have tried to test this hypothesis by studying pigeon breeders who (unlike the previous study by Radermecker et al1Radermecker M Bruwier M Francois C et al.Anti-P1 activity in pigeon breeders serum.Clin Exp Immunol. 1975; 22: 546-549PubMed Google Scholar) were not selected for respiratory disease. The results of the present study by Radermecker and Bruwier indicate that 18 percent (ten) of 56 P1-negative pigeon breeders had anti-P1 antibody and that the proportion with precipitins to pigeon serum was nearly identical in P1-positive (13 percent [27/212]) and in P1-negative (16 percent [9/56]) individuals. Furthermore, Radermecker and Bruwier observed that pulmonary disease was equally reported among P1-positive and P1-negative individuals. These investigators concluded that the P1 blood phenotype does not play a role in the occurrence of respiratory complaints among pigeon breeders. It is of interest to note that the newly reported data, which are based on unselected pigeon breeders, are in disagreement with the original data of Radermecker et al,1Radermecker M Bruwier M Francois C et al.Anti-P1 activity in pigeon breeders serum.Clin Exp Immunol. 1975; 22: 546-549PubMed Google Scholar which were biased toward significant pulmonary disease (since the breeders studied were ascertained through a respiratory disease clinic1Radermecker M Bruwier M Francois C et al.Anti-P1 activity in pigeon breeders serum.Clin Exp Immunol. 1975; 22: 546-549PubMed Google Scholar). Although the incidence of P1-negative breeders was essentially identical in the original series (23 percent)1Radermecker M Bruwier M Francois C et al.Anti-P1 activity in pigeon breeders serum.Clin Exp Immunol. 1975; 22: 546-549PubMed Google Scholar and in the new unselected series (21 percent [56/268]), the incidences of anti-P1 antibody and of precipitins to pigeon serum are significantly lower among pigeon breeders in the unselected series, when compared to the original series1Radermecker M Bruwier M Francois C et al.Anti-P1 activity in pigeon breeders serum.Clin Exp Immunol. 1975; 22: 546-549PubMed Google Scholar (anti-P1Radermecker M Bruwier M Francois C et al.Anti-P1 activity in pigeon breeders serum.Clin Exp Immunol. 1975; 22: 546-549PubMed Google Scholar antibody, χ2 [Yates] = 2.74 and P < 0.05 [onetailed] precipitáis, χ2 [Yates] = 5.43 and P < 0.01 [onetailed]). The decreased incidence of antibodies to the P1 antigen and pigeon serum among the breeders in the unselected series suggests a lesser degree of immunization and less respiratory exposure to antigen in the newly studied group. In addition, although the individuals studied were questioned with regard to respiratory disease, it was not reported if any had respiratory complaints sufficiently severe to require attendance at a respiratory disease clinic. Thus, although Radermecker and Bruwier have found an equal incidence of “respiratory disease” among P1-positive and P1-negative individuals in the present series, it is not clear whether there is a difference in the degree of severity between the breeders in the unselected series and the original one.1Radermecker M Bruwier M Francois C et al.Anti-P1 activity in pigeon breeders serum.Clin Exp Immunol. 1975; 22: 546-549PubMed Google Scholar The current study of Radermecker and Bruwier does not direct itself to the question raised originally in my editorial, which is the possible relationship between the P1-negative phenotype and significant respiratory disease, but rather asks the following questions: (1) are unselected pigeon breeders as immunized as those selected for respiratory disease; and (2) does the P1 blood phenotype play a role? The answer appears to be that unselected pigeon breeders are not as immunized as those selected by attendance at a respiratory disease clinic. The original hypothesis, as stated previously, can only be tested by studying individuals selected for specific respiratory disease and matched to suitable controls, and not by studying individuals with vaguely defined clinical conditions. An individual attending a respiratory disease clinic can be expected to have more severe respiratory disease than a person with respiratory complaints who does not attend a clinic. Pigeon Breeder's Disease and P Blood GroupsCHESTVol. 72Issue 4PreviewTo the Editor: Full-Text PDF