Objective:To explore the clinical characteristics and outcomes of pediatric kidney transplantations at a single center and discuss the related clinical issues.Methods:From January 1990 to October 2019, clinical data were analyzed retrospectively for 244 pediatric renal transplants. The youngest recipient was aged 1.8 years and the median age of pediatric recipients was 12.2 years. The major disease was primary or hereditary glomerulonephritis ( n=160, 69.0%), congenital anomalies of kidney and urinary tract (CAKUT), cystic renopathy and other hereditary nephropathies ( n=55, 23.7%). The donor sources included traditional deceased donor ( n=42, 17.2%), living-related donor ( n=19, 7.8%) and organ donation ( n=183, 75.0%). The median age of donors was 2 years (0-51) and the median weight 12.0(2.7-72.0) kg. From January 2013 to October 2019, 170 cases), the major induction immunosuppression regimen was anti-thymocyte globulin (ATG) ( n=110, 64.7%) or basiliximab ( n=58, 34.1%). The maintenance regimen was tacrolimus + mycophenolic acid (MPA) + glucocorticosteroids. Finally the outcomes and the complications were analyzed. Results:The survival rates of 244 kidney allograft recipients were 98.1%, 94.5% and 93.4% and the graft survival rates 92.6%, 84.2% and 82.0% at 1/3/5 years respectively. Ten recipients died of accident ( n=2, 20.0%), pneumonia after transplantation ( n=2, 20.0%) and intracranial hemorrhage ( n=2, 20.0%). Thirty-three recipients lost their allografts mainly due to intravascular thrombosis in graft ( n=5, 14.3%), acute rejection ( n=5, 14.3%) and death ( n=9, 25.7%). Besides, among 109 deceased donor allograft recipients, the postoperative outcomes were delayed graft function recovery (DGF) ( n=27, 24.8%), arterial thrombosis ( n=6, 5.5%), venous thrombosis ( n=1, 0.9%), graft perirenal hematoma ( n=6, 5.5%), raft artery stenosis ( n=10, 9.2%) and graft ureteral fistula ( n=1, 0.9%). The incidence of acute rejection was 17.5% and 23.2% at 1/3 year respectively. The recurrent rate of primary disease was 6.9%, including primary FSGS ( n=3, 42.9%) and IgA nephropathy ( n=2, 28.6%). At 1/3 year post-operation, the incidence of pulmonary infection was 16.9% and 22.4% and the incidence of urinary tract infection 26.9% and 31.7%. Excluding recipients with graft failure, the estimated glomerular filtration rate (eGFR) at 1/2/3 year postoperatively was (80.3±25.2), (81.4±27.8) and (71.8±27.6) ml/(min·1.73 m 2)respectively. Conclusions:The outcomes of pediatric renal transplantations are excellent at our center. Future efforts shall be devoted to optimizing the strategies of donor kidney selection and strengthening preoperative evaluations, perioperative and postoperative managements for improving the long-term outcomes of pediatric renal transplantations.

Objective: To explore the clinical and prognostic features of lipoprotein glomerulopathy (LPG) in renal allografts. Methods: Retrospective analysis was performed for two case of LPG in renal allografts. The onset time was 6 and 9 years after living transplantation respectively. Initial symptoms included proteinuria and hypoproteinemia. Color Doppler ultrasound showed an enlarged graft size and greater parenchymal echogenicity. One patient had hyperlipemia and elevated apolipoprotein E (ApoE). Methylprednisolone pulse was offered with an early control of hyperlipidaemia and proteinuria by fenofibrate and angiotensin-converting enzyme inhibitors (ACEIs). Yet it had no effect on graft function. The definite diagnosis was made by graft biopsy. Pathological examination indicated non-homogeneous lipid deposition in glomerular capillary, glomerular sclerosis, mesangial hypercellularity and tubular atrophy. Results: During a follow-up period of 8 and 10 years post-transplantation, two cases eventually lost their grafts within 2 and 1 year after biopsy respectively. With long-term dietary control and drug therapy, regular dialysis continued and both awaited a second transplantation. Conclusions LPG is generally steroid-resistant and refractory in renal allografts. And routine biopsy is recommended for patients with a high risk of occurrence. Early controls of hyperlipemia and hypoproteinemia and other risk factors should be also properly managed.

Objective To explore the clinical outcome of renal transplantation and analyze the risk factors influencing the kidney allograft survival after transplantation.Methods The clinical data of 524 cases of renal transplantation between January 2007 and December 2015 were retrospectively analyzed.Serum creatinine was determined,and glomerular filtration rate(GFR) was estimated.The 1-,2-and 3-year patient and graft survival after transplantation was calculated.Adverse events were recorded.Results The median follow-up time was 17.2 months.The 1-,2-and 3-year graft survival rate after transplantation was 97％,95.8％ and 95.3％,respectively.The 1-,2-and 3-year patient survival rate after transplantation was 97.8％,97％ and 97％,respectively.The eGFR was (67.6 ± 24.1),(68.9±24.2) and (72.7 ± 26.2) ml·min-1 ·1.73 m-2 at 1st,2nd and 3rd year after transplantation.The incidence of delayed graft function(DGF) was 20.6％ (108/524).Multivariate analysis revealed donor type (P =0.005) and the terminal creatinine (P＜0.001) were the independent risk factors of DGF.Elder recipients (P =0.004),recipients with diabetes(P =0.031),preoperative positivity of panel reactive antibody(PRA) (P =0.023),and donor with hypertension (P =0.046) were risk factors influencing the kidney allograft survival.Conclusion Kidney transplantation showed good outcomes at 3rd year after transplantation.The recipient age,recipient's history of diabetes,preoperative PRA and donor's history of hypertension are independent risk factors for renal graft survival.

Objective To explore the clinicopathologic characteristics of polyomavirus nephropathy (PyVN) in renal transplantation.Methods Clinicopathological data from 101 cases of PyVN from January 2006 to October 2016 in our hospital were collected and analyzed retrospectively.There were 72 males and 29 females.The mean time from operation to the diagnosis of PyVN was 16.5 months (2.2-63.9 months),with 86 cases (85.1％) occurring within 2 years.The indications for biopsy included elevated serum creatinine in 81 cases (80.2％),elevated serum creatinine with proteinuria in 13 (12.9％) cases,active BK virus(BKV) infection in 5 cases (5.0％) and proteinuria in 2 cases (2.0％).Results BK viruia was detected in 98 (97.0％) recipients with viral loads of 1.5 × 109 (0-9.0 × 1011) copies/ml,and BK viremia in 80 (79.2％) recipients with viral loads of 1.8 × 104 (0-2.1 × 107) copies/ml.5 patients lost their graft function at biopsy and the other 96 patients reserved graft function with serum creatinine of 187.0 μmol/L.After 20.1 (3.7-109.6) months of follow-up,19 (18.8％) patients lost their graft function.The average serum creatinine of the 77 patients with graft function was 165.0 μmol/L,with no statistical difference (P ＞ 0.05) compared with that of patients at diagnosis.There were 18 cases of stage A,72 cases of stage B and 11 cases of stage C with 5-year allograft cumulative survival of 92.9％,82.8％ and 55.6％,respectively.Conclusions PyVN can occur within 5 years after renal transplantation,mostly within 2 years.The typical clinical manifestations include elevated serum creatinine,BK viruia and BK viremia.The severe the histopathological lesions were correlated the worse the clinical prognosis.

Objective To analyze the necessity of anti-human leukocyte antigen (HLA)antibody monitoring and graft biopsy on early diagnosis of antibody-mediated rejection (AMR). Methods Fifty-one recipients with de novo donor specific antibody (dnDSA)were screened and chosen. Donor specific antibody (DSA)and its ability to bind with C1 q were evaluated. Pathological biopsy of the kidney graft was performed. The recipients diagnosed with AMR were divided into the unstable and stable kidney function groups. Type of DSA,binding ability of the complement and Banff score were statistically compared between two groups. Kaplan-Meier survival analysis of the kidney graft in the recipients from non-rejection, unstable and stable kidney function groups was performed. Results Type of HLA antibody,mean fluorescent intensity (MFI)of DSA,C1 q binding ability and C4d deposition in peritubular capillary did not significantly differ between the unstable and stable groups (all P>0. 05 ). Histomorphologically,the Banff score of microvasculitis,endarteritis,renal tubule-interstitial nephritis,transplantation glomerulopathy and renal tubular atrophy-stroma fibrosis did not significantly differ between two groups (all P>0. 05 ). In the unstable group,the accumulated survival rate of the kidney graft was significantly lower compared with that in the stable group,which was significantly lower than that of their counterparts who were ineligible for pathological diagnosis (P=0. 002). Conclusions It is necessary to perform regular anti-HLA antibody monitoring and pathological puncture examination after renal transplantation,which contributes to early detection and diagnosis of AMR.

BACKGROUND:The immune cells of renal al ograft recipients have always been the hot spot of research. However, there are few studies addressing the immune cellsubsets in renal al ograft recipients before operation. OBJECTIVE:To investigate the proportional distribution of immune cellsubsets in renal al ograft recipients before operation. METHODS:Fifteen de novo living-related renal transplant recipients were enrol ed in this study with 15 healthy volunteers, aged 18-40 years, as healthy controls. Flow cytometry was employed to observe the proportion of the immune cellsubsets by extracting peripheral venous blood of al participants. RESULTS AND CONCLUSION:In the renal al ograft recipients, the proportions of CD4+CD25+T cells, the proportion of CD4+CD25+/CD4+T cells, CD19+B cells, CD19+CD5+B cells, CD19+CD27+B cells, NKG2A/NK cells, and NKG2A/NKG2 cells were al lower than those in the healthy controls;however, the proportion of CD38+IgD-/CD19+B cells and NKG2D cells were higher than those in the healthy controls. The difference of the proportion of immune cellsubsets aforementioned between the two groups was statistical y significant (P<0.05), while no difference was observed in other subsets. Immune cellsubsets in renal al ograft recipients before operation could be used to assess the immune status of the recipients, and also could be seen as the basal control for postoperative immunological monitoring.

Objective To study the influence of donor GFR on the early renal function in recipients undergoing living donor transplantation.Methods A total of 172 living donor transplant recipients in our kidney transplantation center from 2006 to 2011 were enrolled into this study.Among them,166 were genetically related (96.5％),while 6 were genetically unrelated (spouses in 5 and other in 1).The predonation GFR was measured by isotope clearance (99mTC-DTPA with few exceptions).The range of donor GFR was 62 to 148 ml/min.The recipients were classified into two groups according to donor graft GFR level (GFR≤45 ml/min,n=76; GFR＞45 ml/min,n =96).The predonation dialysis,cold and warm ischemia time,antibody induction,immunosuppressive regimens and HLA mismatch were not significantly different between two groups.Results There were no significant differences in the incidence of postoperative acute rejection and delay graft function (DGF).The postoperative Scr of GFR＞45 ml/min group in 1 week,1 month,3 months and 1 year was lower compared with the GFR ≤45 ml/min group,and only the difference of Scr in 1 week was significantly different (P＜0.05).A repeated-measure ANOVA revealed no significant differences were found in Scr variation of two groups during the first year after transplantation.Conclusions Predonation GFR of the donor has effect on the Scr of postoperative Ⅰ week of recipients,not on the Scr within a year.Recipients with graft GFR＞45 ml/min have lower Scr levels.

Objective To analyze diagnostic value of renal biopsy in living-related kidney transplantation and the influence of kidneys from marginal donors on the early prognosis of recipients. Methods According to donors age and risks of donors, 142 living-related kidney transplant recipients from February 2004 to July 2008 were divided into marginal donor group (51 cases) and non-marginal donor group (91 cases). Renal biopsy was performed on 49 kidneys Postsurgical serum creatinine (Scr), the lowest Scr and post-transplant complications were analyzed between the two groups. Results Pathological changes were detected in 13 cases. The Scr at 4 weeks, 12 weeks, 6 months post-transplant and the lowest level of Scr in marginal donor group were higher than those in non-marginal donor group (all P<0.05). There were no significant differences of Scr levels at 12 months, 24 months, 36 months post-transplant, the time required to return to the lowest Scr, and post-transplant complications between two groups (all P>0.05). Conclusions The early clinical efficacy of the marginal donor is ideal, but the baseline of Scr of recipients is higher than that of recipients with kidneys from non-marginal donors. Renal biopsy has an important diagnostic and therapeutic value for both donors and recipients.

Objective To analyze the characteristics of tuberculosis (TB) in renal-transplant recipients from our hospital, and summarize the corresponding experiences in diagnosis and management.Methods A retrospective study was performed on 61 documented post-transplant TB cases out of the 2842 patients who received kidney transplantation in the First Affiliated Hospital of Sun Yat-sen University between Jan.1991 and Dec.2010.Results TB in the post-renal-transplant population in our hospital displayed the following characteristics:(1) High incidence (2.1％ ).54.1％ recipients were diagnosed within the first year post-transplant; (2) Lung was the most common site (77.0 ％).There was high prevalence (60.7 ％) of extra-pulmonary TB (lymphatic TB,23.0 ％; pleuritis,13.1 ％; graft,11.5％); (3) Fever (83.6 ％),cough (55.7 ％),sputum (41.0 ％) were the most common clinical manifestations.There were also emaciation (3.3 ％) and enlargement of lymph nodes (18.0 ％); (4) Chest X-ray and CT were of great value during TB diagnosis while purified protein derivative of tuberculin (PPD) skin test had little diagnostic value with a negative result in 56 cases (91.8 ％) ; (5) Liver function damage ( 16.4 ％),kidney function injury (39.3 ％) and peripheral nerve toxicity (3.3 ％) were the main adverse reactions of anti-tuberculosis chemotherapy,also the major cause of anti-TB failure; (6) Pre-transplant TB (17 cases) increased the probability of TB recurrence (4 cases,23.5 ％) post-transplantation; (7) The post-transplant TB patients were accompanied with cellular immune deficiency,resulting in overlapping infection of bacteria,viruses and fungi (19.7 ％); (8) 1- and 3-year patient/graft survival rate of patients with post-transplant TB was 85.2 ％/78.7 ％ and 85.2 ％/75.4 ％ respectively. The accumulative mortality rate reached to 14.8％,while overlapping infection was the major cause of death (66.7 ％).Conclusion Chinese renal transplant recipients still face a high risk of TB because of their immunecompromised state and epidemiological prevalence of the disease. For the high mortality rate and associated serious complications,rapid diagnosis and effective anti-TB chemotherapy are of great value for TB population.

Objective To investigate the characteristics of BK virus (BKV) infection in renal transplant recipients. Methods A total of 243 renal recipients from our clinic within 48 months after transplantation were enrolled as the trial group and 82 healthy people as the control group. Urine and peripheral blood samples of these two groups were harvested for urinary sediment BKV cytology by Decoy cell counting and BKV DNA by real-time PCR. Results The positive rates of urinary Decoy cell, BKV viruria and viremia were 35.4%, 36.6% and 16.9% in trial group, and 4.9%, 20.7% and 2.9% in control group, respectively. In trial group, the medians of urinary Decoy cell, urinary BKV and peripheral blood BKV were 6/10 HPF, 1.00×104 copy/ml and 6.87×103 copy/ml respectively, while in control group, they were 2/10 HPF, 1.10×104 copy/ml and 2.24×1(3 copy/ml. Compared with the healthy people, the positive rates and the levels of BKV DNA in urine and peripheral blood of recipients were significantly higher. The amount of urinary Decoy cells was positively correlated to urinary BKV load (r=0.636, P＜0.01). Conclusions BKV replication is easier to happen in renal recipients as compared to healthy people. Counting of urinary Decoy cells is convenient, useful and sensitive to evaluate BK viruria and viremia in renaltransplant recipients. BKV DNA detection in urine and peripheral blood can be used to screen the evidence of BK reaction in order to prevent irreversible graft damage by BKV.[ Key words ] Kidney transplantation; BK virus; Kidney diseases; Decoy cells