伊藤 泰平

<p>The aim of the present study was to reveal the long-term outcomes of pancreas transplantation and to elucidate the risk factors that affect pancreatic graft survival in Japan.<br/>We retrospectively analyzed a total of 246 cases of pancreas transplantation. After the exclusion of cases involving graft loss resulting from perioperative complications, the cases of 233 patients who underwent pancreas transplantation were divided into two groups: the simultaneous pancreas and kidney transplantation (SPK) group (n=188) and the pancreas transplantation after kidney and pancreas transplantation alone (PT) group (n=45) ; each group was analyzed to determine the factors associated with pancreatic graft survival.<br/>The pancreatic graft survival rates at 1, 5, and 10 years after transplantation were 86.8%, 82.9%, and 74.9%, respectively, in the cases of SPK; and 85.1%, 42.2%, and 31.7%, respectively, in the cases of pancreas transplantation after kidney and pancreas transplantation alone, which amounted to a significant difference （P=4.81×10^‐5）. Episodes of rejection made pancreatic survival significantly lower in both groups. A multivariate analysis using Cox proportional hazards regression revealed that the preoperative period of diabetes （hazard ratio, 1.065; 95%CI, 1.009-1.125; P=0.02341） was significantly associated with pancreatic graft survival in the SPK group. HLA-A mismatch （hazard ratio, 2.153; 95%CI, 1.073-4.321; P= 0.03101） was the only factor associated with pancreatic graft survival in the PT group. Although the difference did not reach statistical significance, it was suggested that induction therapy with a T-cell depleting antibody would improve the rate of pancreatic graft survival in both groups.<br/>In spite of the severe shortage of donors in Japan, simultaneous pancreas and kidney transplantation should be performed for type 1 diabetes patients with end-stage renal failure in the earlier stage, and HLA-A matching should be considered when selecting recipients to improve the rate of pancreatic graft survival in the PT group.</p>

膵臓移植における造影超音波検査(CEUS)の有用性について検討した。膵臓移植症例に対し、移植直後、術後1、3、5、7、14、21、28日目に造影超音波検査を行った。CEUS導入初期7例では、移植直後において、Doppler超音波検査で移植膵脾静脈内の血流を検出できたのは1例であったのに対して、CEUSでは全例検出可能であった。また2例で脾静脈内に血栓を認めた。抗凝固療法を強化、延長するのみで、抗血栓療法、intervention、手術などの追加治療をすることなく、静脈血栓は時間経過とともに溶解し、完全に消失した。CEUSは移植膵静脈血栓のスクリーニングに有用で、血栓形成を認めた症例でも、CEUSで静脈灌流を確認することで十分保存的に経過観察可能であることが判明した。膵臓移植後のCEUSで膵実質内の組織灌流を評価すると、移植直後の組織灌流に症例によってかなりばらつきがあることが判明した。膵臓移植直後のCEUSから求められるΔTp(V-P)による移植膵組織内灌流は移植後の膵内分泌機能を反映していることが明らかとなった。