Distinct Distribution of Immunocytes in a Retropharyngeal Lymphadenopathy Associated with Kawasaki Disease: A Case Study Compared with Tonsillitis

Abstract

Objectives: Retropharyngeal lesions are often associated with Kawasaki disease (KD). A 4-year-old male first presented a peritonsillar and retropharyngeal abscess-like lesion. Surgical tonsillectomy was performed to avoid a risk of mediastinal abscess, but he fulfilled the diagnostic criteria of KD after the operation. This prompted us to perform a histological study on the KD tonsils.

Methods: The histopathology of the KD tonsil specimens were compared with hypertrophic tonsils obtained from 4 patients with chronic tonsillitis unrelated to KD assessed by the immunostainings.

Results: KD tonsils showed small lymphatic follicles and neutrophil infiltration in the peritonsillar muscle layer, with no evidence of vasculitis or abscess formation. The KD tonsils exclusively showed (1) predominant activated CD4+ T cells in the perifollicular interstitium, (2) sparse scattering of CD68+ monocytes/macrophages in the lymphatic follicles, and (3) polyclonal carcinoembryonic antigen-positive cells in the lymphatic follicles and venules with the high endothelial cells.

Conclusions: The uniquely distributed immunocytes suggest the inflammatory process of KD involving the pathogen-associated molecules.

Keywords: Cervical lymphadenopathy; Immune activation; Pathogen-associated molecular patterns; Vasculitis.