Lung and peripheral blood T lymphocytes IFN-γ production in infliximab-associated pulmonary tuberculosis.

We present the pattern of cellular immune response at both the levels of the diseased lung and peripheral blood in a case of pulmonary tuberculosis following infliximab treatment for Crohn's disease. A 40 year-old man who had received two courses of infliximab (5 mg/kg) was admitted with intermittent fever, cough and dyspnoea. Diagnosis of active pulmonary tuberculosis with positive sputum culture for Mycobacterium tuberculosis was made. At the time of diagnosis, CD3 lymphocytes from peripheral blood showed a moderate presence of cells producing IFN-γ (20%) and broncho-alveolar lavage (BAL) cells exhibited low levels of IFN-γCD3 lymphocytes (3.2%) After antitubercular treatment an increase in the percentage of CD3 lymphocytes producing IFN-γ (48%) was found on BAL cells whilst, on peripheral blood, a decrease in the percentage of IFN-γ producing CD3 lymphocytes was observed. This observation suggests a possible immune pathway responsible for development of anti-tumor necrosis factor-α-associated tuberculosis. © 2005