献腎移植後のATN期間中に発生した拒絶反応の診断と治療成績

Abstract

1)心停止ドナーより体内局所灌流冷却後に摘出された68腎の腎移植後の生着率は1年, 3年, 5年でそれぞれ95.4%, 93.8%, 81.4%であった. 2)術後の透析不要(I群)は16例, 51例はATNのために術後の透析を要した.うち, 41例はATN期間中の拒絶反応を認めなかったが(II群), 他の10例は拒絶反応を併発し治療を要した(III群). 3)III群のATN期間はII群のATN期間よりも有意に長期化し, 血清クレアチニン値もIII群で最も高く, II群, I群の順に低下した.5年腎生着率は, I群, II群では共に85%を越えていたが, III群では59.3%であった. 4)III群で拒絶反応は移植腎生検の組織診断を根拠になされており, 現時点では病理診断に優るものはなく, 超音波ドップラーや腎血管シンチグラフィー, MRIなどではATNと拒絶反応の鑑別が困難である

Diagnosis of acute rejection (AR) is difficult during acute tubular necrosis (ATN), and a delay of rejection treatment could result in negative impacts on the renal transplant outcome. At our center, 68 cadaveric kidneys were transplanted during the past 7 years. The 1-, 3- and 5-year graft survival rates were 95.4%, 93.8% and 81.4%, respectively. After the transplants, 16 patients had immediate graft function (G-I), 51 patients experienced ATN for 12.0 +/- 9.3 days, and one patient had a non-functioning graft due to diffuse arteriolar thrombosis caused by DIC in the donor. During ATN, 41 patients had no rejection episodes (G-II) and 10 patients had ARs (G-III). Nine patients were treated with bolus steroid and one with steroid and OKT-3. Although scintigraphic and sonographic examinations were routinely employed, only the histopathological findings of needle biopsies were helpful for the diagnosis of AR during ATN. When the transplant outcome was compared, the serum creatinene level was highest in G-III and lowest in G-I (1.48 vs 1.06 mg/dl, p < 0.05). The posttransplant ATN period was also longer in G-III compared to G-II (23.9 vs 9.1 days, p < 0.005). The 5-year graft survival rate was 85.2% in G-I, 88.0% in G-II and 59.3% in G-III. We conclude that routine serial renal biopsies should be scheduled when ATN develops after the cadaveric renal transplant, since only the histopathological diagnosis is reliable during ATN.