Posttransplantation lymphoproliferative disorder

A 29-year-old woman with cystic fibrosis presented with abdominal pain, which had worsened over 3 days, together with low-grade fever and chills. The pain, which radiated from the central to the lower abdomen, increased with movement and had been present since bilateral lung transplantation 4months earlier. She had occasional nausea and nonbilious vomiting. The medical history included laparotomy for postoperative small bowel obstruction, diabetes mellitus, and osteoporosis. Medications included metoclopramide, lactulose, prednisone, tacrolimus, azathioprine, valacyclovir, itraconazole, cotrimoxazole, alendronate, lansoprazole, pancreatic enzymes, insulin, calcium, folate, and a multivitamin. Examination was normal except for mild periumbilical tenderness. Laboratory tests revealed mild anemia and a slight nonanion gap acidosis. Two small duodenal ulcers were discovered at EGD. Biopsy specimens revealed mild duodenitis with superficial ulceration. At