310.7: Spleen preservation attenuates GVHD in multivisceral transplant recipients.

Abstract

Purpose: The immunological benefits of the spleen are well acknowledged, but splenectomy is often performed in recipients of multivisceral transplantation. Technical reason and the lack of room in the abdominal cavity are the key arguments to justify removal of the native spleen. We aimed to analyze the beneficial role of the spleen in MVTx recipients in a series of pediatric intestinal transplantation. Patients and methods: A total of 103 IT (55MV, 25SB, 22CLSB, 3MMV) were performed in 84 patients (male-60%-, mean age 5.3yrs) between 1999 and 2018. Mean time on the waiting list was 272days waiting list mortality was 25%. Main indications for the transplant on the first instance were short bowel syndrome (69%), motility disorders(12%) and epithelial diseases(9.5%). For the present study we included only pediatric (<18 years) cases that underwent multivisceral transplantation. Patients were divided patients in three groups, native spleen preservation, native spleen removal and spleen graft inclusion. We analyzed survival, GVHD, hemolytic disorders. Results: From the whole series, only 55 patients were included, all of them received a multivisceral graft. The spleen was included in the graft in 18.1% of patients, splenectomy was performed in 40%, in several of them after failed attempt of preservation; and native spleen was preserved in 41.8% Rejection in different forms was more frequent in patients who preserved the spleen, 4% presented humoral rejection, and acute cellular rejection was two times and chronic rejection four times more frequent compared with patients who underwent splenectomy. None of the patients with the spleen included in the graft presented humoral or chronic rejection, PTLD was also (1.8 times) more frequent in this group. The proportion of GVHD was significantly lower in the group of spleen preservation compared to splenectomy and graft spleen (RR 2.75, OR 3.33) (p<0.05). We also found a trend towards less hemolytic disorders in patients with spleen preservation. Conclusion: Native spleen preservation demonstrated to attenuate the occurrence and severity of GVHD in pediatric MVTx recipients. This technique should be considered in all patients, although technical difficulties, prolonged ischemia of the graft and other factors can preclude the success of the procedure.