Total selective deficiency of serum and secretory IgA associated with farmer's lung.

We present a case of total IgA deficiency associated with farmer's lung. The IgA deficiency is combined with the IgE one. IgA are absent both in the serum and in the bronchial secretions; they are present on the surface of B-lymphocytes, also after the enzymatic surface digestion and resynthesis test is performed. With intravenous perfusion of human gamma globulins, during repeated courses, IgA reach a normal level and exceed it, despite the IgA concentration in the perfused compound is very low and despite the fact that injected gamma globulins are not detectable with electrophoretic method. IgA never appear in the bronchial secretion. The association between both IgA and IgE deficiency, with this pulmonary disease, differential diagnostics, and therapeutical features, are discussed.