Three cases are described showing a seasonal exacerbation of their nephrotic syndrome in association with an atopic trait and grass pollen allergy. The first patient has a history of four consecutive seasonal relapses each requiring steroid therapy. Following a course of desensitization injections he has now been free of relapse for 3 consecutive years. The second patient has also had a recurrent steroid-sensitive nephrotic syndrome often associated with the pollen season and allergic rhinitis. In this patient a course of cyclophosphamide has reduced his tendency to relapse. The third patient who has been on continuous prednisone therapy shows a seasonal increase in proteinuria.
Serum changes in the first two patients include: a seasonal rise in total and grass pollen specific IgE; the continued presence of grass pollen specific IgG throughout the year but with a reduction during the pollen season in association with a more pronounced fall in the total IgG level; a depression in the C3 level in association with each major relapse; a mild rise in the I-K titre and a positive result in the C1q test for circulating complexes. A renal biopsy performed on the first patient when in relapse showed minor histological changes only and IgG. IgM, IgA, IgD, IgE, C3 and fibrinogen were undetectable by immunofluorescent examination. The probable mechanism for the development of proteinuria in these patients is discussed.