Treatment outcomes of tonsillectomy were investigated in 5 Japanese patients with anaphylactoid purpura, all of whom had a history of chronic tonsillitis. The patient group was composed of 2 males and 3 females and the age ranged from 18 to 51 years with a median age of 28 years. The patients were followed for 6 months to 10 years after tonsillectomy. All of the skin lesions disappeared in one patient, 80% of those in 3 patients, and 50% in one, during the follow-up period. To determine the histological characteristics of the tonsils, the T-nodules, B-lymphoid follicles, and the areas of mixed T- and B-cells were quantitatively identified on the tissue section stained by CD20 antibody. The areas were compared with those of each of the 5 tonsils obtained from age-matched patients with recurrent tonsillitis and with IgA nephropathy. The area of Tnodules was significantly larger in both tonsils from patients with anaphylactoid purpura and with IgA nephropathy compared to those from patients with recurrent tonsillitis. These clinical and histological data remind us that anaphylactoid purpura may be an entity of tonsil-related diseases such as IgA nephropathy.
