An Uncommon Case of Graft vs Host Disease Colitis After Lung Transplant

Abstract

A 50 year-old Caucasian man was hospitalized four weeks after bilateral lung transplant for pulmonary sarcoidosis, with four days of abdominal pain, vomiting and diarrhea. His immunosuppression consisted of prednisone, mycophenolate mofetil (MMF) and tacrolimus, as well as post-transplant infection prophylaxis. His physical exam showed tachycardia, abdominal tenderness to the midepigastric area without rebound or guarding, hyperactive bowel sounds, and without hepatomegaly. His labs were only significant for elevated transaminases (AST 101, ALT 269). Stool studies including culture, C. difficile, viral and parasitic serologies were negative. Colonoscopy showed severe inflammation with ulceration, pseudomembranes, erythema, and denuded mucosa in the right colon and terminal ileum. Pathology showed severe active colitis, crypt drop out, and severe cryptitis. Immunohistochemical stains were negative for CMV and HSV. The presence of donor lymphocyte chimerism in the patient's peripheral blood confirmed the diagnosis of graft versus host disease (GVHD). IV methylprednisolone was started for 10 days but the patient's diarrhea persisted. He received one dose of infliximab then transitioned to extracorporeal photophoresis (ECP) for steroid resistant GVHD. A follow-up colonoscopy showed complete healing of the colonic mucosa. GVHD typically occurs 20-100 days after organ transplantation and is categorized by immunocompetent donor T cells attacking immunosuppressed host cells. GVHD is characterized by skin, liver, and gastrointestinal symptoms such as abdominal pain, vomiting, diarrhea, and intestinal bleeding. Drug-induced colitis (i.e. MMF), inflammatory bowel disease, or infectious colitis can mimic GVHD colitis. Pathologic evaluation of intestinal tissue can differentiate between these etiologies. Rectal biopsies have the highest sensitivity for diagnosis, even with endoscopically normal mucosa. Initial treatment consists of IV systemic steroids, with consideration for budesonide to treat gastrointestinal symptoms. Steroid refractory disease is treated with biologics, further immunosuppression, monoclonal antibodies, or ECP. There are only 11 cases of GVHD after lung transplant reported in the literature with high mortality rates. Death is typically due to pancytopenia and sepsis. GVHD is a rare complication after lung transplant, therefore extra vigilance is required to make the diagnosis and initiate treatment promptly.