2022 Volume 44 Issue 3 Pages 199-204
Background. A paradoxical reaction is a phenomenon that causes a transient exacerbation of existing lesions or fever after the initiation of tuberculosis treatment, and it is often difficult to differentiate from other diseases. Case Presentation. A 35-year-old woman with Crohn's disease was referred to our hospital for the evaluation of fever and an abnormal shadow on chest radiography. She was diagnosed with pulmonary tuberculosis and miliary tuberculosis based on a positive sputum smear for acid-fast bacilli; and a positive polymerase chain reaction for Mycobacterium tuberculosis, and treatment with anti-tuberculous drugs was initiated. A negative sputum smear for acid-fast bacilli and the regression of the lesions were confirmed after the initiation of treatment. However, she developed worsening cough 15 months after the initiation of treatment. Furthermore, chest computed tomography revealed enlargement of the mediastinal lymph nodes, enlargement of the consolidation in the right lower lobe, and a bronchial polyp at the truncus intermedius. A sputum smear for acid-fast bacilli was positive. Bronchoscopic biopsy of each lesion was performed, and a histopathological examination revealed caseous necrosis and epithelioid cells; however, no acid-fast bacilli were detected in the biopsy specimens. We continued anti-tuberculosis treatment because we considered that these lesions had formed as a result of a paradoxical reaction. Treatment was discontinued when cultures of bronchoscopic specimens to detect acid-fast bacilli were confirmed to be negative. Conclusion. Physicians should be aware that paradoxical reactions can occur late in the course of treatment and may have multiple manifestations, and a histological diagnosis should be performed to exclude other diseases.
