Chronic rhinitis in HTLV-1 carriers: a histopathologic study

The nasal histopathology of HTLV-1 carriers with chronic rhinitis is unknown. Objective: To describe the histopathological features of HTLV-1 carriers with chronic rhinitis. Materials and Methods: Biopsies of nasal mucosa of ten HTLV-1 carriers with chronic rhinitis (eight patients with allergic rhinitis and two patients with non-allergic rhinitis) were studied using a light microscope. Samples from ten patients with allergic rhinitis not infected with HTLV-1 were used as controls. Results: Subepithelial fibrosis was more pronounced in patients with allergic rhinitis infected with HTLV-1 (p=0.01), while the basement membrane thickness was greater in controls (p=0.03). There was a trend towards less eosinophilia and edema among those infected with HTLV-1, without statistical significance (p=0.2). For the lymphocytic infiltrate, there was no difference between infected and not infected patients with allergic rhinitis (p=1.0). Subepithelial fibrosis associated to moderate or small number of lymphocytes were found in the two HTLV-1 carriers with non-allergic rhinitis. Conclusions: This study suggests HTLV-1 may modify the histopathology of allergic rhinitis, especially by promoting subepithelial fibrosis, and may be related to chronic non-allergic rhinitis with lymphocytic infiltrate.