Tuberculous hilar lymphadenopathy progressing after isoniazid administration

Right hilar lymphadenopathy was the only radiologic finding in an immunocompetent 19-year-old man with a positive whole blood interferon-γ enzyme-linked immunosorbent test (QuantiFERON-TB-2G). Because his initial treating physician did not notice the lung lesion on chest radiography, isoniazid (INH) monotherapy was begun with subsequent progression of the lymphadenopathy. We must take into consideration even hilar lymphadenopathy in patients with tuberculosis (TB) disease without detectable Mycobacterium (M.) tuberculosis organisms, because INH monotherapy may result in progression of the TB lesion.