Structural and Immunological Characteristics of Chronically Inflamed Adenotonsillar Tissue in Childhood

Abstract

Recurrent or chronic adenotonsillar infections mainly affect children and frequently involve otherwise healthy subjects. Therefore, having excluded systemic immunological deficiencies, this disease may be due to a local dysfunction of the epithelial structures at either the rhino or oropharyngeal level. The aim of the present investigation was to analyze structural and immunological aspects of tonsils and adenoids in subjects who underwent adenotonsillectomy because of recurrent inflammatory episodes with fever. Histological studies and analyses of the cytokine patterns were carried out in palatine tonsils and adenoid samples from 105 patients who underwent adenoidectomy and bilateral extracapsular tonsillectomy for chronic inflammatory hypertrophy of these organs; 46 of the 105 cases examined presented hyperkeratosis of the crypt epithelium; in the remaining 59, the epithelium was hyperplastic with no signs of keratosis. Scanning electron microscopy revealed a continuous epithelial surface of polygon-shaped flattened cells with fissures towards the cryptic depressions. Titration of interleukin-1␤ and tumor necrosis factor alpha in serum and tissues demonstrated higher concentrations in the adenotonsillar specimens, whereas the rise in interleukin-6 was more modest.There are still some controversies among specialists in internal medicine, pediatrics, and otorhinolaryngologists concerning the diagnostic and therapeutic approach to recurrent and chronic inflammatory conditions of adenoids and tonsils in children.Over the last few decades, immunobiological techniques have allowed the identification of tonsillar cells responsible for inflammatory immune reactions (2, 5). Recurrent or chronic adenotonsillar infections mainly affect children and frequently involve otherwise healthy subjects. Therefore, having excluded systemic immunological deficiencies, this disease may be due to a local dysfunction of the epithelial structures, at either the rhino or oropharyngeal level.Several authors (4, 6, 8) have tried to explain why and how a modification in the balance between the local immunological function of the host and the infectious agents would lead to a clinical process characterized by recurrent inflammatory events.The complex histological configuration of the parenchyma is fundamental for the uptake and presentation of antigens to the subepithelial immunocompetent cells. This allows the whole organ to act as a functional unit and hence to play an important role in fighting microorganisms. It may therefore be hypothesized that persistent local inflammatory reactions in adenotonsillitis may, with time, lead to histomorphological changes and functional deficiencies in defense barriers (3).The aim of the present investigation was to analyze structural and immunological aspects of tonsils and adenoids in subjects who underwent adenotonsillectomy because of recurrent inflammatory episodes with fever. MATERIALS AND METHODS Patients.We selected 105 children affected by chronic inflammatory hypertrophy of palatine tonsils an...

Toll-like receptor expression in the human nasopharyngeal tonsil (adenoid) and palantine tonsils: A preliminary report

“…Furthermore, both tissues are enclosed in epithelial cells, which have been suggested to be a major source of proinflammatory cytokine production in adenoid and tonsil tissue. Epithelial cells express TLRs [4,5,18] and have been shown to be instrumental in innate immune responses, which influence the subsequent adaptive immune response [5,9,11,18]. Therefore, the nasopharyngeal and palantine tonsils are clearly capable of producing proinflammatory and antimicrobial molecules, which shape the immune response [5,12,13].…”

Enzymatic study of tonsil tissue alkaline and acid phosphatase in children with recurrent tonsillitis and tonsil hypertrophy

“…In our study, we identified two types of histological changes in the RT group. The first type was hypertrophied tonsils with a large number of follicles with bright and active germinal centres, which was previously shown in patients with tonsillitis [27][28][29]. In contrast, atrophic tonsils showed only one or two dark follicles, suggesting poor immunological activity.…”

The role of matrix metalloproteinases in recurrent tonsillitis

“…The pathogenic mechanism of tonsillar hypertrophy is unknown and lacks a proper infectious, immunological or environmental explanation [6]. Probable contributions of extracellular matrix turnover dysregulation to the tonsillar hypertrophy are also not still well known.…”

“…Several authors have tried to explain why and how a modification in the balance between the local immunological function of the host and the infectious agents would lead to a clinical process characterized by recurrent inflammatory events [6,[17][18][19]. Playing a central role in ECM turnover, MMPs proteolytically activate or degrade a variety of nonmatrix substrates including chemokines, cytokines, growth factors, and junctional proteins.…”