Unusual Presentation of Orofacial Granulomatosis Leading to the Incidental Diagnosis of Idiopathic Pulmonary Fibrosis: A Case Report.

Orofacial granulomatosis (OFG) is a rare chronic inflammatory disorder characterized by non-caseating granulomatous inflammation involving the oral and maxillofacial region. Its heterogeneous clinical presentation and overlap with systemic granulomatous diseases often make diagnosis challenging. We report the case of a 54-year-old woman presenting with a four-month history of progressive mandibular mucosal hypertrophy mimicking an epulis-like lesion. Clinical examination revealed multiple pedunculated, firm, painless mucosal lesions localized to the anterior mandibular ridge in a fully edentulous patient, without lip swelling or fissured tongue. Histopathological analysis demonstrated non-caseating granulomatous inflammation composed of epithelioid histiocytes, lymphocytic infiltrates, and Langhans-type multinucleated giant cells. A comprehensive multidisciplinary evaluation was performed to exclude systemic granulomatous diseases, including Crohn's disease, sarcoidosis, hypersensitivity reactions, infectious diseases, and Melkersson-Rosenthal syndrome. High-resolution computed tomography (HRCT) revealed bilateral basal and subpleural reticulations, architectural distortion, and ground-glass opacities consistent with a probable usual interstitial pneumonia (UIP) pattern. Pulmonary function testing demonstrated a restrictive ventilatory defect with reduced diffusing capacity of the lungs for carbon monoxide (DLCO). Following multidisciplinary assessment and the exclusion of alternative etiologies, a diagnosis of idiopathic pulmonary fibrosis (IPF) was established according to American Thoracic Society/European Respiratory Society (ATS/ERS) criteria. This finding was considered incidental and unrelated to the oral lesions. Management included systemic corticosteroid therapy, followed by surgical excision of the fibrotic lesions using an electrosurgical approach to facilitate prosthetic rehabilitation. Postoperative evolution was favorable, with no recurrence after two years of follow-up, although pulmonary function progressively deteriorated due to IPF. This case highlights the diagnostic challenges associated with atypical OFG presentations and emphasizes the importance of a rigorous multidisciplinary approach to exclude systemic diseases while avoiding inappropriate causal associations.