Examination and identification of oral tuberculosis infections

Tuberculosis (TB) is a chronic, infectious granulomatous disease caused by Mycobacterium tuberculosisand less frequently by Mycobacterium bovis and atypical mycobacteria.۱ It ranks among the top ۱۰ causes ofdeath world-wide.۲ India accounts for nearly one third of the global burden of TB.۳ The average prevalence of allforms of the disease in the country is estimated to be ۵.۰۵ per thousand and average incidence of smear-positivecases, ۸۴ per lakh.Morgagni reported the first case of oral TB seen as lingual involvement in ۱۷۶۱. Based onreviews published before ۱۹۵۰, oral TB accounted for ۰.۱–۵% of all TB infections. With advances inchemotherapy and improvement in public health and hygiene, the rate deteriorated. However, nowadays, oralmanifestations are re-appearing alongside many forgotten extrapulmonary infections as a consequence of theemergence of drug-resistant TB and the emergence of Acquired Immuno-deficiency Syndrome (AIDS) Oral TBrarely occurs as a result of primary inoculation and invasion of mycobacteria owing to the cleansing effects ofsaliva, the relative paucity of lymphoid tissue and the action of antagonist commensals. It occurs morecommonly, secondary to pulmonary TB, which leads to increased concentration of mycobacteria in the oralcavity. A breach in the oral mucosa as a result of tobacco use, traumatizing dentures or poor oral hygiene leads tolocalization of the mycobacteria and infection. Oral TB may manifest as ulceration, swelling, granulomatousplaques and nodules. The varied presentation, similarity in clinical morphology to other oral conditions and rarityof occurrence make the diagnosis of oral TB challenging. The present article seeks to review the prevalence andpresentation of TB in the oral cavity and also report a unique case of gingival tuberculosis, histologicallymimicking plasma cell gingivitis, another rare condition of the oral cavity that occurs as a hypersensitivityreaction to antigens sourced in food flavoring agents and spices.

کلیدواژه ها:

OralTB ، Incidence ، prevalence ، presentation ، differential ، oral mucosa ، Mycobacterium