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Updated: Aug 15, 2025

A 3D Human Lung Tissue Model for Functional Studies on Mycobacterium tuberculosis Infection
Published on: October 5, 2015
A buccal mucosa ulcer as the first sign of tuberculosis
Paulo S S Pina1, Celso A Lemos1, Suzana C O M de Sousa1
1Department of Stomatology, Faculty of Dentistry, Universidade de São Paulo (USP), Sao Paulo, SP, Brazil.
Abstract:
Tuberculosis (TB) is an infectious disease caused mostly by Mycobacterium tuberculosis. Oral lesions caused by this disease are not common, and most of them represent secondary involvement of the initial pulmonary focus. Therefore, the discovery of lung tuberculosis because of the investigation of oral lesions is rare. This paper reports a case of a 61-year-old male patient who presented with a painfully ulcerated lesion in labial commissure and buccal mucosa, without any comorbidities or symptoms associated. An incisional biopsy was performed, and histopathology showed a chronic granulomatous lesion extending to involve the underlying muscle. Based on these findings, investigation for tuberculosis was suggested. Chest radiography displayed excavated macronodular lesions suggestive of an inflammatory-infectious/granulomatous process of bronchogenic dissemination. The search for acid-alcohol-resistant bacillus in sputum was positive. After using drug therapy for tuberculosis for 3 months, there was a total regression of the oral lesions, in addition to weight recovery in the period. Thus, in patients with isolated oral mucosa lesions, we must consider the possibility of oral manifestation of systemic diseases, even without typical clinical signs and symptoms.
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