Tuberculosis infection following anti-TNF therapy in inflammatory bowel disease, despite negative screening

We present two patients with inflammatory bowel disease who, despite negative tuberculosis screening, developed a de novo tuberculosis infection after the start of anti tumor necrosis factor alpha treatment. We discuss current screening methods and their limitations, the approach after positive screening and the timing to resume anti-TNFα treatment after TB infection. We shortly mention the immune reconstitution inflammatory syndrome (IRIS), described in a few cases after the stop of anti-TNFalpha while treating the tuberculosis infection. We conclude with some remaining questions concerning tuberculosis in IBD patients.