Recurrent and chronic inflammations of Waldeyer's ring in childhood: infectious,structural and immunological features

摘要

Objective: To evaluate certain infectious, structural and immunological aspects of the adenoids and tonsils in patients submitted to adenotonsillectomy due to chronic inflammation or massive hypertrophy. Materials and methods: In the first phase, bacterial flora and lymphocytic population were analyzed in the tonsils and adenoids removed from 19 children; in the second phase, histological studies and analysis of the cytokine pattern were carried out in palatine tonsils and adenoids from 105 patients submitted to adenoidectomy and bilateral extracapsular tonsillectomy. Results: The presence of Haemophilus influenzae, Streptococcus pneumoniae and S beta-hemolytic was comparable in both tissues; the most frequently isolated pathogen being H. influenzae. A higher percentage of T3 and T4 lymphocytes was observed in adenoids than in the tonsils. Histologically, of the 105 cases examined, 46 presented hyperkeratosis of the crypt epithelium; in the remaining 59, the epithelium was hyperplastic with no signs of keratosis. A comparison of findings, in serum and tissues, showed a higher concentration of interleukin (IL)-1 p and tumor necrosis factor-alpha (TNF-a) in the adenotonsillar specimens, whereas the rise in IL-6 was more modest. Conclusions: The impaired immunological reactivity of the tonsils would appear to be mediated by a change in the epithelial compartment which results in impaired antigen uptake rather than by the lymphatic compartment which only reacts to the repeated stimuli. The high levels of cytokines lead, with repeated infectious stimuli, to activation and proliferation of endothelial cells and fibroblasts which result, with time, in the progressive replacement of immunologically active tissue with fibrotic tissue which is, therefore, immunologically silent.