Long-term Changes in Spleen Volume After Living Donor Liver Transplantation in Pediatric Recipients

Background. Living donor liver transplantation (LDLT) is a definitive procedure for splenomegaly caused by liver cirrhosis and portal hypertension, but splenomegaly persists in some patients. The aim of this study was to clarify the long-term changes in the spleen volume after LDLT. Methods. The 13 pediatric patients who survived for >8 years after LDLT were retrospectively analyzed. We calculated the spleen volume/standard spleen volume (SV/SSV) ratio by automated computed tomography (CT) volumetry. We assessed the spleen volumes before LDLT, at roughly postoperative week (POW) 4, at postoperative year (POY) 1, at POY 5, and at POY 10. Results. With regard to SV as evaluated by CT volumetry, there were no consistent trends, with median values as follows: before LDLT, 282.5 (71-641) cm(3); POW 4, 252 (109-798) cm(3); POY 1, 222.5 (97-948) cm(3); POY 5, 263.5 (123-564) cm(3); and POY 10, 377 (201-1080) cm(3). In contrast, the SV/SSV ratio decreased chronologically as follows: before LDLT, 5.0 (0.7-6.0); POW 4, 3.7 (2.3-4.3); POY 1, 2.2 (1.7-6.3); POY 5, 1.7 (1.1-5.4); and POY 10, 1.4 (1.1-6.9). In the remote phase after LDLT, many cases showed a trend toward an improved SV/SSV ratio, but splenomegaly was prolonged without improvement in 3 cases (23.1%) with portal vein complications and advanced fibrosis. Furthermore, all 3 cases showed a decreased platelet count due to hypersplenism. Conclusion. Splenomegaly requires a long time to demonstrate an improvement. In cases without an improvement of splenomegaly, we should suspect abnormalities in the graft liver and portal hemodynamics.