Primary mediastinal lymph node tuberculosis diagnosed using endobronchial ultrasound-guided transbronchial needle aspiration: Literature review and case report

Tuberculosis bacilli can enter the human body through the respiratory system, digestive system, or skin and mucous membranes, with the respiratory tract representing the primary point of entry. Once inside the body, tuberculosis bacilli can enter the bloodstream and attack other organs, including the lymphatic system. One manifestation associated with lymphatic tuberculosis infiltration is the presence of large hilar and mediastinal lymph nodes, which are common in children and classified as primary tuberculosis. A diagnosis of primary tuberculosis in adults is often overlooked by doctors due to its low frequency. When a single enlarged mediastinal lymph node is observed, most doctors suspect other causes, especially malignancy. Determining the correct diagnosis for enlarged hilar and mediastinal lymph nodes can be difficult because diagnostic interventions in this area are challenging to perform. We report a clinical case of primary lymph node tuberculosis in an adult, confirmed by endobronchial ultrasound-guided transbronchial needle aspiration. We aim to provide doctors with a more comprehensive approach for diagnosing this disease.