Case 340.

A 36-year-old woman with an otherwise unremarkable medical history was diagnosed with moderate to severe Crohn disease and was started on infliximab. One year later, infliximab was discontinued due to intolerance, and the patient began azathioprine and mesalazine treatment, achieving stable disease. Eight months after discontinuing infliximab, during a Crohn disease flare-up, an urgent abdominal CT examination was performed, partially documenting the lung bases, as shown in Figure 1. The patient maintained her therapy, with remission of the flare-up. Sixteen months after discontinuing infliximab and 8 months after initial abdominal CT, she presented to the emergency department with pleuritic chest pain and occasional dyspnea. She was afebrile, and her physical examination and routine laboratory test results were unremarkable. Chest CT was performed (Fig 2). The patient was started on analgesics and referred to a pulmonology appointment, where biopsy of the lesion was recommended. One month after chest CT, while awaiting the biopsy results, the patient again presented to the emergency department with recurring similar symptoms after a brief period of symptomatic improvement. Physical examination and laboratory test results remained unremarkable. This visit prompted a new chest CT examination (Fig 3).