Pregnancy Complications and Impact on Kidney Allograft After Kidney Transplantation in IgA Nephropathy.

Pregnancy in kidney transplantation (KT) recipients has been challenging because of the high risk of maternal, fetal, and renal complications. Although patients with immunoglobulin A nephropathy (IgAN)-chronic kidney disease (CKD) are at a high risk for hypertension in pregnancy (HIP), the maternal risk in KT recipients with IgAN as the etiology remains unclear. We retrospectively reviewed the medical records of pregnant KT recipients who delivered at our hospital. The incidence of maternal and fetal complications and the impact on kidney allografts between the group with IgAN as the primary kidney disease and the group with other primary diseases were compared. The analysis included 73 pregnancies in 64 KT recipients. The IgAN group had a higher incidence of HIP than the non-IgAN group (69% vs. 40%, p = 0.02). IgAN as primary kidney disease and interval from transplantation to conception were associated with HIP (OR 3.33 [1.11-9.92], p = 0.03, OR 0.83 [0.72-0.96], p < 0.01, respectively). The 20-year graft survival or prevention of CKD stage 5 in group with IgAN was lower than that in the group with other primary disease (p < 0.01). KT recipients should be informed of the risk of HIP and possibility of long-term worsening of postpartum renal function.

Immunological risk and complement genetic evaluations in early onset de novo thrombotic microangiopathy after living donor kidney transplantation: A Japanese multicenter registry.

BACKGROUND: Thrombotic microangiopathy (TMA) after kidney transplantation (KTx), particularly early onset de novo (dn) TMA, requires immediate interventions to prevent irreversible organ damage. This multicenter study was performed to investigate the allogeneic clinical factors and complement genetic background of dnTMA after KTx. METHODS: Perioperative dnTMA after KTx within 1 week after KTx were diagnosed based on pathological or/and hematological criteria at each center, and their immunological backgrounds were researched. Twelve aHUS-related gene variants were examined in dnTMA cases. RESULTS: Seventeen recipients (15 donors) were enrolled, and all dnTMA cases were onset within 72-h of KTx, and 16 of 17 cases were ABO incompatible. The implementation rate of pre-transplant plasmaphereses therapies were low, including cases with high titers of anti-A/anti-B antibodies. Examination of aHUS-related gene variants revealed some deletions and variants with minor allele frequency (MAF) in Japan or East Asian genome databases in genes encoding alternative pathways and complement regulatory factors. These variants was positive in 8 cases, 6 of which were positive in both recipient and donor, but only in one graft loss case. CONCLUSIONS: Although some immunological risks were found for dnTMA after KTx, only a few cases developed into TMA. The characteristic variations revealed in the present study may be novel candidates related to dnTMA in Japanese or Asian patients, but not pathogenic variants of aHUS. Future studies on genetic and antigenic factors are needed to identify factors contributing to dnTMA after KTx.

Long-term prolonged-release tacrolimus outcomes in living donor kidney transplantation: The Japan Academic Consortium of Kidney Transplantation study-II.

OBJECTIVES: To evaluate the 10-year efficacy and safety of a prolonged-release tacrolimus-based combination immunosuppressive regimen on longer-term outcomes in living donor kidney transplantation. METHODS: Data from Japanese living donor kidney transplant recipients (n = 410) maintained on continuous prolonged-release tacrolimus-based immunosuppression from 2009-2013 were analyzed with a median follow-up of 9.9 years. RESULTS: A prolonged-release, tacrolimus-based combination regimen provided death-censored graft failure and all-cause death rates at 10 years of 7.0% and 6.8%, respectively. In multivariable analyses, acute and chronic rejection and 'throughout' (new-onset plus preexisting) diabetes mellitus were risk factors for death-censored graft failure. Recipient age ≥ 65 years, throughout diabetes mellitus and malignancy were common risk factors for all-cause death. Throughout diabetes mellitus was the most common risk factor for both death-censored graft failure and all-cause death. Additional analyses showed 10-year cumulative rates of death-censored graft failure were 14.0% and 5.4% for recipients with or without preexisting diabetes mellitus, respectively (log-rank test: p = 0.009). All-cause death rates were 12.7% and 5.4% in the preexisting and non-diabetes mellitus groups, respectively (log-rank test: p = 0.023). CONCLUSIONS: In this real-world, retrospective, living donor kidney transplantation study, a prolonged-release tacrolimus-based immunosuppressive combination regimen provided 10-year death-censored graft failure rates of 14.0% and 5.4% in diabetes mellitus and non-diabetes mellitus patients, respectively; Similarly, 10-year all-cause death rates were 12.7% and 5.4% in diabetes mellitus and non-diabetes mellitus patients, respectively. To our knowledge, the data in this study are the first to provide 10-year transplant outcomes in living donor kidney transplant recipients under prolonged-release tacrolimus-based regimen.

The interaction between post-transplant anemia and allograft function in kidney transplantation: The Japan Academic Consortium of Kidney Transplantation-II study.

BACKGROUND: The interaction between post-transplant anemia (PTA) and allograft function in kidney transplantation has not been evaluated directly. PTA, defined by WHO/AST criteria, was investigated in 1307 adult kidney transplant recipients between 2000 and 2015 (median follow-up, 7 years). METHODS: We investigated the impact of hemoglobin (Hb) on graft failure (non-censored for death) and their interactions, time-dependent Cox model, and subgroup analysis were used. RESULTS: PTA prevalence was 43.6% at 7 years and varied according to allograft function, recipient sex, and follow-up period. Decreased Hb considering the time-varying effect was associated with an increased risk of graft failure (hazard ratio = 1.83, 95% CI 1.66-2.02, P < 0.001). In subgroup analysis, allograft function (post-transplant time-averaged estimated glomerular filtration rate and cut point: 45 mL/min/1.73 m2) had significant interaction (P = 0.032). The 7-year graft failure rate in recipients with PTA and high eGFR was 7.7% (HR 1.52, 95% CI 1.25-1.84), whereas in those with PTA and low eGFR was 19.9% (HR 2.00, 95% CI 1.74-2.31). CONCLUSIONS: The unfavorable impact of PTA was significantly enhanced by low allograft function. PTA is likely to be associated with graft failure due to interaction with allograft function. Therefore, we should consider both Hb level and allograft function while determining the treatment strategy.

Post-donation satisfaction in kidney transplantation: a survey of living donors in Japan.

BACKGROUND: No studies using a valid, standardized method to measure post-donation satisfaction levels among living kidney donors (LKDs) have been published. METHODS: Donor satisfaction levels were measured using the Japanese version of the Client Satisfaction Questionnaire-8 (CSQ-8), a validated, self-report questionnaire. To identify factors related to post-donation satisfaction levels, we compared donors' sociodemographic and psychological characteristics and health-related quality of life (HRQoL), using the Short Form-36 Health Survey (SF-36), as well as recipients' clinical characteristics and SF-36 scores between donors with and without low satisfaction. In addition, donors' perceptions of the donation results and transplant procedure were assessed using measures that we developed. RESULTS: The mean (standard deviation [SD]) CSQ-8 score for the 195 participants was 26.9 (3.4). Twenty-nine (14.9%) respondents with total scores < 1 SD below the mean CSQ-8 score were placed into the low satisfaction group. Multiple logistic regression analysis demonstrated that lower perceptions of receiving adequate information prior to transplantation (odds ratio [OR] = 0.17; 95% confidence interval [CI] = 0.079-0.379; p < 0.001), lower optimism according to the Life Orientation Test (OR = 1.24; 95% CI = 1.045-1.470; p = 0.014), and increased serum creatinine levels in the paired recipient (OR = 0.05; 95% CI = 0.250-1.011; p = 0.054) independently increased the odds of having less satisfaction with donation. CONCLUSIONS: Our findings suggest that careful pre-donation education and more detailed informed consent may be needed, especially in LKDs with low constitutional optimism.

Higher immunoglobulin A nephropathy recurrence in related-donor kidney transplants: The Japan Academic Consortium of Kidney Transplantation study.

OBJECTIVE: To investigate the 10-year biopsy-proven recurrence rates and risk factors for immunoglobulin A nephropathy recurrence in kidney transplant recipients. METHODS: We included 299 kidney transplant recipients from 1995 to 2015, who had biopsy-proven underlying immunoglobulin A nephropathy and underwent zero-hour biopsy. The primary end-point was recurrence of immunoglobulin A nephropathy. We compared clinical, treatment and graft failure among those with and without recurrent immunoglobulin A nephropathy. A time-to-recurrence analysis was carried out using the competing risk analysis and time-dependent Cox model. RESULTS: Of 299 recipients, 80 had recurrent immunoglobulin A nephropathy (66.3% with clinical biopsy and 33.7% with protocol biopsy, post-transplant biopsy rate: 90.6%). The 10-year recurrence rate was 34.3% (95% confidence interval 27.6-41.1). Related-donor transplantation (hazard ratio 2.28, P = 0.009) and post-transplant increased proteinuria (hazard ratio 1.59, P < 0.001) were identified as potential risk factors for immunoglobulin A nephropathy recurrence. The 10-year rates were 41.5% in related donor recipients and 16.3% in unrelated donor recipients. There was no conclusive evidence that the calcineurin inhibitor, antimetabolites, basiliximab and rituximab reduce immunoglobulin A nephropathy recurrence. Immunoglobulin A nephropathy recurrence was associated with an increased risk of death-censored graft failure (hazard ratio 5.29, 95% confidence interval 1.39-20.17, P = 0.015). However, related donor itself was not associated with an increased risk of graft failure. CONCLUSIONS: The present results have clinical implications in that the signs of recurrent immunoglobulin A nephropathy should be evaluated carefully in recipients receiving related-donor transplants. There is a need for further studies related to genetic and/or familial interactions in kidney transplant recipients with immunoglobulin A nephropathy and related donors.

Once-daily vs twice-daily tacrolimus for de novo living kidney transplantation patients including ABO/HLA compatible and incompatible: A randomized trial.

Tacrolimus (TAC) is available as a twice-daily capsule (TAC-BID), once-daily capsule (TAC-QD), and once-daily tablet. Recipients with ABO-incompatible/anti-human leukocyte antigen (HLA)-incompatible transplantation were excluded in previous trials and have thus not been evaluated. We conducted a 5-year trial to determine whether TAC-QD is noninferior to TAC-BID for transplant outcomes. Adults who underwent de novo living kidney transplantation were randomly assigned (62 TAC-QD; 63 TAC-BID). We did not exclude ABO-/HLA- incompatible transplantation. TAC was initiated 7 days preoperatively (0.10 mg/kg/d). Mycophenolate mofetil, methylprednisolone, and basiliximab were administered. The primary endpoint was graft failure (non-censored for death). We performed a noninferiority test. The noninferiority margin was 10% in risk difference. Five-year graft failure rates were 6.5% and 9.5% for TAC-QD and TAC-BID, respectively (noninferiority, P = 0.009). The estimated glomerular filtration rates were similar between the groups (noninferiority, P < 0.001). TAC-QD did not have point estimates of risk difference above the inferiority margin in any assessed endpoints. However, a tendency of interaction was observed between biopsy-proven acute rejection and the follow-up period. In a living kidney transplant population with 40% of patients with ABO/HLA incompatibility, the effect of TAC-QD was not appreciably worse on various clinical transplant outcomes than that of TAC-BID over 5 years.

Interstitial fibrosis is the critical determinant of impaired renal function in transplant glomerulopathy.

AIM: Transplant glomerulopathy (TG) is a feature of chronic antibody-mediated injury in the glomerular capillaries in renal transplant recipients. TG is generally associated with proteinuria; however, renal function at the diagnosis of TG varies. This study aimed to determine which morphological abnormalities are associated with renal function and proteinuria at the diagnosis of TG. METHODS: A total of 871 renal transplantations were performed at Tokyo Women's Medical University between 2005 and 2013. TG was diagnosed in 127 biopsies from 58 (6.7%) recipients. Renal function was evaluated by the estimated glomerular filtration rate (eGFR). Proteinuria was assessed by a dipstick test: positive for +1 and over. RESULTS: At diagnosis, of 127 biopsies, 72, 37, and 18 had mild, moderate, and severe TG (Banff cg). The severity of TG was not associated with decreased eGFR at the time of biopsy (cg1: 36.1 ± 14.8, cg2-3: 38.8 ± 14.5 mL/min per 1.73 m(2) , P = 0.25), whereas the severity of interstitial fibrosis (IF) (Banff ci) was significantly associated with decreased eGFR (ci0-1: 42.75 ± 13.32, ci2-3: 27.69 ± 11.94 mL/min per 1.73 m(2) , P < 0.0001). The multivariate analysis revealed that IF was the only independent risk factors for decreased eGFR (OR = 4.38, P = 0.0006). Meanwhile, TG was identified as the only independent risk factor for the incidence of proteinuria (OR = 2.67, P = 0.014). CONCLUSION: Interstitial fibrosis was a critical determinant of impaired renal function at the diagnosis of TG. The severity of TG was significantly associated with proteinuria, but did not contribute to renal dysfunction.

The presence of antibodies against the AD2 epitope of cytomegalovirus glycoprotein B is associated with acute rejection after renal transplantation.

The aim of this study was to evaluate the association between antibodies against cytomegalovirus (CMV) glycoprotein B (gB) and acute rejection after transplantation. Seventy-seven consecutive renal transplant recipients in a D + /R+ setting were studied. Biopsy-proven rejection occurred in 35% of the recipients. Among these recipients, 85% had antibodies against CMV gB. The rate of acute rejection was significantly higher in recipients with antibodies against gB than in those without them. Antibodies against gB can be a useful predictor of acute rejection in renal transplant recipients in a D + /R+ setting.

[A CASE OF TESTICULAR TUMOR DIAGNOSED DUE TO ACUTE SCROTUM].

A 32-year-old man visited the emergency department complaining of the right scrotal pain, which occurred suddenly during sexual intercourse. Palpation revealed induration and tenderness on the caudal side of the right testis. Ultrasonography revealed a mosaic-like mass on the caudal side of the testis and no difference in blood flow between the right and left testes. The patient underwent a thorough examination the next day. Although the blood test did not show elevated tumor marker levels, testicular MRI revealed a mass with heterogeneous signal in the right scrotum. Subsequently, the patient was referred to another hospital for surgery. The pathological examination revealed a mixed germ cell tumor: seminoma (60%), teratoma (20%), and embryonal carcinoma (20%). One year postoperatively, the patient has had no recurrence. Testicular tumors are rarely discovered in acute scrotum, and few such cases have been reported. Torsion of the tumor, hemorrhage, necrosis, rupture, and infection have been reported as mechanisms of occurrence. When acute scrotum is diagnosed, testicular tumor should be considered as a differential diagnosis.

A Case Report of Successful Renal Transplantation After Surgically Treated Type A Aortic Dissection.

BACKGROUND: Aortoiliac lesions can influence the results of kidney transplantation and increase technical difficulties during surgery. Aortic dissection (AD) is a rare and infrequently reported event before transplantation, whereas immediate optimal perfusion is paramount for kidney transplantation. Thus, adequate blood flow imposed by the flow from the true lumen must be considered when choosing a target inflow vessel. CASE PRESENTATION: A 67-year-old man on dialysis with end-stage renal disease caused by immunoglobulin A nephropathy was referred for kidney transplantation. He had successfully undergone conventional Stanford type A AD surgery 3 years ago. Pretransplant contrast-enhanced computed tomography angiography revealed termination of the distal intimal flaps within the common iliac arteries. Dilation of the descending aorta was also observed. Based on the meticulous vascular assessment, including consultation with the cardiovascular surgery department, the right internal iliac artery (IIA) was considered usable for anastomosis. He underwent living unrelated kidney transplantation from his 66-year-old wife. The patency and blood flow in the right IIA were also verified using intraoperative findings. Without any special procedure, we used a side-to-end arterial anastomosis between the donor renal artery and recipient IIA. After vascular clamp removal, the allograft was perfused homogeneously and immediately functioned. CONCLUSION: Patients receiving previous surgery for type A AD can successfully undergo kidney transplantation if the patency of the iliac arteries from the true lumen is confirmed by perioperative evaluation, and the artery can be carefully clamped to avoid possible further dissection.

A Case Report of Successful Kidney Transplantation in a Patient With Autosomal Dominant Polycystic Kidney Disease Who Underwent Thoracic Endovascular Aortic Repair for Type B Aortic Dissection.

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is associated with several cardiovascular disorders, including aortic dissection, which preferentially occurs at the thoracic or abdominal level. Because there are few case reports describing surgical repair for aortic dissection followed by renal transplantation in patients with ADPKD, kidney transplantation performed after repair for aortic dissection remains challenging. CASE PRESENTATION: A 34-year-old Japanese man with end-stage renal disease secondary to ADPKD underwent thoracic endovascular aortic repair for complicated acute type B aortic dissection 12 months earlier. A contrast computed tomography scan before transplantation revealed an aortic dissection involving the descending aorta proximal to the common iliac arteries and confirmed multiple large bilateral renal cysts. After simultaneous right native nephrectomy, the patient underwent preemptive living-donor kidney transplantation obtained from his mother. Intraoperatively, we noted that dissection of the external iliac vessels was difficult because of dense adhesions. Arterial clamping was performed immediately below the bifurcation of the internal iliac artery to prevent further aortic dissection of the external iliac artery. After end-to-end anastomosis to the internal iliac artery was completed and the vascular clamp was released, the kidney began to produce urine immediately. CONCLUSION: This case suggests that kidney transplantation in patients undergoing endovascular aortic repair for aortic dissection can be performed by adequately applying a vascular clamp proximal to the internal iliac artery during vascular anastomosis.

Acute vascular rejection after renal transplantation and isolated v-lesion.

Histopathological changes of acute vascular rejection (AVR) are characterized by intimal arteritis and transmural arteritis. According to the Banff 1997 classification, the quantitative criteria for intimal arteritis (v score) are classified: v0, v1, v2, and v3. According to Banff '09 classification, AVR may fall into one of four categories: acute T cell-mediated rejection (ATMR) Type IIA, ATMR Type IIB, ATMR Type III, and acute antibody-mediated rejection (AAMR) Type III. Both cellular and humoral immunity play roles in vascular rejection, and in some cases, AVR may be provoked by anti-donor antibodies. Anti-rejection therapies were effective in most of the v1 cases but were less effective in the v2 cases and were ineffective in the v3 cases. Some reports have indicated that the prognosis of grafts exhibiting AVR is poor, but in our series, the outcome of AVR was relatively good using recent immunosuppressive protocols. A definition for "isolated v-lesion" was originally characterized by arteritis with minimal interstitial inflammation and tubulitis. The 11th Banff conference was concluded that "isolated v1-lesions" comprised two types, T cell-mediated rejection and injury, and did not have any independent prognostic significance. However, we speculate that "isolated v-lesion" might be regarded as AAMR and ATMR.

Clinical and pathological analysis of transplant glomerulopathy cases.

UNLABELLED: Transplant glomerulopathy (TG) is involved in the criteria of chronic active antibody-mediated rejection (c-AMR) in Banff '09 classification. PATIENTS: TG was diagnosed in 58 renal allograft biopsy specimens (BS) from 37 renal transplant patients. RESULTS: Among 58 BS of TG, 27 BS were mild (cg1), 16 were moderate (cg2), and 15 were severe (cg3). Peritubular capillaritis was present in 49 (84%), transplant glomerulitis was seen in 47 BS (81%), interstitial fibrosis and tubular atrophy in 47 (81%) and the thickening of the peritubular capillary (PTC) basement membrane (PTCBM) in 44 (76%), and interstitial inflammation was present in 26 BS (45%). C4d deposition in PTC was presented in 32 BS (55%). The circulating anti-HLA alloantibody was detected in 38 times (76%), of which 27/38 (54%) were donor-specific antibodies. Deterioration of renal allografts' function after biopsies was seen in 12 patients (32%) with six of them lost their graft. CONCLUSIONS: We suggest that histopathological changes of TG accompanying by transplant glomerulitis, peritubular capillaritis, the thickening of the PTCBM, and circulating anti-HLA antibodies might indicate c-AMR, even if C4d deposition in PTC is negative. The prognosis of the graft exhibiting TG was relatively good under the present immunosuppression protocol in short time.

Role of Early Serial Renal Transplant Allograft Protocol Biopsies in Living Kidney Transplantations.

PURPOSE: This study aimed to analyze the incidence of subclinical rejection (SCR) in kidney transplantation patients and risk factors associated with SCR. METHODS: We assessed 80 protocol biopsies taken within 2 years postoperatively in 41 adult patients who underwent living donor kidney transplantation between 2017 and 2020. All patients were on immunosuppressant therapy that included tacrolimus, mycophenolate mofetil, and steroids. RESULTS: The prevalence of Banff Borderline classification at 3, 6, and 12 months after transplantation was 4%, 5%, and 8 %, respectively, whereas none of the biopsies met the Banff criteria for acute T cell-mediated rejection throughout the study period. Active antibody-mediated rejection (ABMR) was only present in 8% of patients at 3 months after transplantation and chronic active ABMR at 6, 12, and 24 months after transplantation was detected in 10%, 13%, and 11% of the patients, respectively. Subgroup analysis revealed that 50% of the 6 patients with preformed anti-donor specific antibodies (DSAs) developed clinical or subclinical active ABMR within 3 months after transplantation, followed by chronic active ABMR according to serial histologic assessment. Conversely, only a small proportion of patients (3%) without preformed DSAs exhibited clinically active ABMR. CONCLUSIONS: SCR occurs too infrequently in patients with low immunologic risk and strong contemporary immunosuppression therapy to justify the diagnostic effort of serial protocol biopsies. However, protocol biopsies remain an indispensable tool in renal transplant monitoring and may be especially important in immunologically high-risk patients with pre-existing DSAs.

A case of transplant glomerulopathy early after kidney transplantation.

UNLABELLED: Transplant glomerulopathy (TG) has commonly been described as a late manifestation of allograft injury, occurring years after renal transplantation. We describe herein a patient who developed TG early (49 days) after kidney transplantation (KTx). CASE REPORT: A 44-yr-old woman received a second living-related KTx from her younger brother in October 2009. Pre-transplant donor-specific anti-human leukocyte antigen antibodies (DSA) were positive for both class I and class II. During the renal transplant operation, she suffered from hyperacute antibody-mediated rejection (AMR) and intravenous immune globulin therapy was immediately performed. Once hyperacute AMR was resolved, accelerated acute AMR occurred on the first post-transplant day (PTD). The renal allograft biopsy performed on PTD 19 diagnosed acute AMR type II. The renal allograft biopsy performed on PTD 49 showed focal lesions of double contours of glomerular basement membranes in some glomeruli. Interstitial fibrosis showed a strong, diffuse staining of C4d in peritubular capillaries (PTCs). The DSA examined on PTD 39 were still positive for both class I and class II. From these histopathological findings of TG, C4d deposition in PTC and presence of circulating DSA, we diagnosed this case to have c-AMR. CONCLUSIONS: TG might be recognized in early after KTx.

The low dose of rituximab in ABO-incompatible kidney transplantation without a splenectomy: a single-center experience.

PURPOSE: A new protocol for ABO-incompatible (ABO-i) kidney transplantation including rituximab was introduced in January 2005 in our institute. This study reviewed the results and evaluated the use of low-dose rituximab in ABO-i kidney transplantation. MATERIAL AND METHODS: Seventy-four de novo ABO-i kidney transplantations were performed at Tokyo Women's Medical University between January 2005 and August 2010. The immunosuppressive protocol was consisting of tacrolimus, mycophenolate mofetil, and methylprednisolone. All the patients received induction therapy with basiliximab. The pre-conditioning protocol included double-filtration plasmapheresis and a single dose of rituximab. A dose of 500 mg/body rituximab was initially employed and yielded excellent results (Group I, n = 24). Afterward, the dose of rituximab was reduced to 200 mg/body in January 2007 (Group II, n = 50). RESULTS: Seventy-four de novo ABO-i recipients were treated with this protocol, and all patients underwent kidney transplantation successfully. Effective elimination of the peripheral blood CD19 cells was observed in both groups. However, the peripheral blood CD19 levels were still low in both groups at 24 months after treatment. CONCLUSION: The patients in Group II showed excellent results similar to Group I. These results suggest that the low dose of rituximab (200 mg/body) is the sufficient dose in ABO-i kidney transplantation.

BK polyomavirus nephropathy complicated with acute T-cell-mediated rejection in a kidney transplant recipient: a case report.

We present a case of severe BK polyomavirus nephropathy (BKVN) complicated with persistent acute T-cell-mediated rejection (ATMR) that progressed to allograft failure. A 54-yr-old man received a living donor kidney transplant from his wife. Approximately four months after transplantation, the patient's serum creatinine (SCr) increased from a baseline value of 1.5-2.4 mg/dL. A histological analysis showed BKVN, and the SV40 antigen was detected in the tubular nuclei. The doses of immunosuppressants were reduced, and immunoglobulin was administered intravenously. The SCr increased further, to 5.3 mg/dL, and a second renal biopsy revealed the presence of severe ATMR. Antirejection treatment was performed, and low-dose cidofovir was started. The SCr decreased, to 3 mg/dL, and BK virus antigen in the serum and urine samples became negative at the time of hospital discharge. However, the histological findings subsequently showed gradually progressive interstitial fibrosis and tubular atrophy, and the SCr increased gradually. Two years after the transplantation, the patient resumed hemodialysis. BK polyomavirus nephropathy is usually treated with a reduction in immunosuppressant therapy, although in some patients, the reduction in immunosuppressants induces a subsequent exacerbation of acute rejection and results in progressive graft failure, which suggests difficulty in treating BKVN after kidney transplantation.

[Renal allograft rupture attributed to coughing while asleep: a case report].

Renal allograft rupture (RAR) is a rare but serious complication of renal transplantation. The most common cause of RAR is acute rejection but other causes have increased in frequency with advances in immunosuppressive therapy. We report a patient with RAR attributed to coughing while asleep. A 53-year-old male received a living-donor renal transplantation for end-stage renal failure due to diabetic nephropathy. The clinical course was satisfactory, and he was discharged on the 12th postoperative day with a serum creatinine level of 1.24 mg/dl. On the 24th morning, he felt sudden swelling and pain over the incision area soon after a big cough. Ultrasound and computed tomography revealed a perinephric hematoma. Emergency surgical exploration showed complete laceration of the abdominal fascia and 4-cm rupture at the anterolateral aspect of the kidney. High intra-abdominal pressure when coughing had torn the fascia, and the graft appeared to have ruptured under the fascial tension. Bleeding was controlled with a polyglactin 910 2/0 mattress parenchymal suture enforced with application of a fibrin tissue-adhesive collagen fleece. Twelve months after the repair, the patient's renal function was stable with a serum creatinine level of 1.3 mg/dl.