Human Papillomavirus Infection as a Rare Etiological Factor in Moderate Squamous Dysplasia of the Trachea.

We report the case of a 42-year-old, non-smoking male admitted with right upper-lobe pneumonia. Chest computed tomography (CT) demonstrated findings consistent with an infectious process. For further evaluation, serial bronchoscopies with biopsy sampling were performed. Histopathological examination revealed moderate squamous dysplasia of the tracheal epithelium, and subsequent immunohistochemical testing detected human papillomavirus (HPV) genotype 45. This case underscores the value of integrating imaging, endoscopic assessment, and molecular diagnostic techniques in the evaluation of atypical pulmonary lesions and highlights the potential role of HPV infection in airway epithelial dysplastic changes.