Apoptotic Colitis in a Liver Transplant Recipient: A Case of Solid Organ Transplant-Associated Graft-Versus-Host Disease.

Solid organ transplant-associated graft-versus-host disease (SOT-GVHD) is a rare but often fatal complication following liver transplantation. A 67-year-old man who underwent deceased donor liver transplantation subsequently developed progressive high-volume diarrhea and severe cytopenias with minimal initial cutaneous involvement. Colonic biopsy demonstrated apoptotic colitis with minimal lamina propria inflammation, suggestive of lower gastrointestinal (GI) GVHD. Donor-recipient chimerism analysis revealed significant donor-derived chimerism in peripheral blood and colonic tissue, confirming the diagnosis of SOT-GVHD. Maintenance immunosuppression was stopped to restore recipient immune function and eliminate donor-derived lymphoid cells; however, there was no clinical improvement. He was subsequently treated with high-dose systemic steroids, resulting in transient improvement. Despite this, he developed worsening diarrhea and pancytopenia, consistent with steroid-refractory GVHD, and passed away. This case emphasizes the need for a high index of suspicion for SOT-GVHD in liver transplant recipients presenting with gastrointestinal symptoms and cytopenias, even in the absence of significant early cutaneous manifestations. Histopathology and donor chimerism analysis of the involved tissue can aid in early diagnosis. Initial therapeutic approaches vary significantly, both withdrawing immunosuppression to elicit a host-versus-graft response and augmenting immunosuppression with systemic steroids have been described. Regardless, SOT-GVHD is associated with a high rate of mortality. Novel approaches for early diagnosis, prevention, and treatment are needed.