Clinicopathological study of renal biopsies after liver transplantation.

OBJECTIVE: To perform a clinicopathological study of patients having renal biopsies after liver transplantation. DESIGN: Case series. SETTING; Queen Mary Hospital, Hong Kong. PATIENTS: All post-liver transplantation patients who had a renal biopsy in the period from January 2000 to December 2010. RESULTS: Eleven renal biopsies were retrieved for review from 10 patients with liver transplantation. The male-to-female ratio was 9:1 (age range, 47-63 years). The median liver transplant-to-renal biopsy interval was 1590 (range, 102-3699) days. The predominant histological changes were interstitial fibrosis and tubular atrophy. Diabetic nephropathy (n=6) and immunoglobulin A nephropathy (n=4) were the commonest glomerulopathies. Only one patient had chronic calcineurin inhibitor nephrotoxicity. With a mean follow-up of 53 months, three patients died 2 to 53 months post-renal biopsy. All surviving patients had chronic renal impairment. Five patients developed end-stage renal failure and four had significant persistent proteinuria. CONCLUSION: Renal pathology was variable after liver transplantation; most biopsies showed complex renal lesions, whilst calcineurin inhibitor nephrotoxicity was rare. The recognition of kidney histology attributable to metabolic derangements after liver transplantation is potentially important in the interpretation of renal biopsy specimens and patient management. The renal outlook of this group of patients is guarded.

Malignancies after kidney transplantation: Hong Kong renal registry.

Manystudies have shown that kidney transplant recipients have a higher incidence of cancers when compared with general population. However, most data on the posttransplant malignancies (PTM) are derived from Western literature and large population-based studies are rare. There is also lack of information about the posttransplant cancer-specific mortality rate. We conducted a population-based study of 4895 kidney transplants between 1972 and 2011, with data from the Hong Kong Renal Registry. Patterns of cancer incidence and mortality in our kidney transplant recipients were compared with those of the general population using standardized incidence ratios (SIRs) and standardized mortality ratios (SMRs) respectively. With 40 246 person-years of follow-up, 299 PTM was diagnosed. The SIR of all cancers was 2.94 (female 3.58 and male 2.58). Non-Hodgkin lymphoma (NHL), kidney, and bladder cancers had the highest SIRs. The overall SMR was 2.3 (female 3.4 and male 1.7) and the highest SMR was NHL. The patterns of PTM differ among countries. Increases in cancer incidence can now translate into similar increases in cancer mortality. NHL is important in our kidney transplant recipients. Strategies in cancer screening in selected patient groups are needed to improve transplant outcomes.

Superior mesenteric artery syndrome complicating dialysis patients with peritoneal failure--report of 3 cases.

We report 3 cases of superior mesenteric artery syndrome in patients previously on maintenance peritoneal dialysis converted to hemodialysis after peritoneal failure. All 3 patients presented with repeated vomiting and severe malnutrition. It is postulated that complications arising from peritoneal dialysis such as peritoneal sclerosis, adhesions and collections after CAPD peritonitis may be important contributing factors for the SMA syndrome in these 3 patients. All of them succumbed within six months of diagnosis. The first 2 patients received gastrointestinal bypass surgery and died post-operatively due to impaired wound healing and nosocomial sepsis. The 3rd patient was treated conservatively with nasoduodenal feeding but succumbed to aspiration pneumonia. It is postulated that complications arising from peritoneal dialysis including peritoneal sclerosis, adhesions and collections after CAPD peritonitis may contribute to the SMA syndrome in these patients. Our experience suggests that SMA syndrome in end-stage renal disease patients is associated with high surgical morbidity and mortality possibly related to their poor pre-morbid condition and pre-existing malnutrition. Aggressive parenteral nutrition should be considered to build up the general status before proceeding to surgical intervention.

Determination of mismatched donor HLA in kidney transplant recipients with unknown donor HLA phenotypes.

OBJECTIVE: To determine donor human leukocyte antigen (HLA) from renal allograft biopsies in transplant recipients whose donor HLA phenotype is not known. METHODS: Renal allograft biopsies were obtained from seven renal transplant recipients when indicated for allograft dysfunction or proteinuria. DNA was extracted fresh from allograft specimens, and HLA typing was performed with polymerase chain reaction-specific sequence primers (PCR-SSP) and polymerase chain reaction-sequence-specific oligonucleotides (PCR-SSO). RESULTS: HLA typing of the seven renal allograft biopsies was composed of both recipient and donor HLA phenotypes, allowing the determination of the donor HLA and the degree of HLA mismatching. CONCLUSIONS: Deducing mismatched donor HLA antigens in renal allograft recipients enables detection of donor-specific antibodies, and the management of humoral rejection, and enables more appropriate selection of a donor organ should future retransplantation be required.

Ultrasound-contrast agent mediated naked gene delivery in the peritoneal cavity of adult rat.

Gene transfer into the peritoneal cavity by nonviral methods may provide an effective therapeutic approach for peritoneal diseases. Herein, we investigated the feasibility and the effectiveness of ultrasound-microbubble-mediated delivery of naked plasmid DNA into the peritoneal cavity in rats. Following the intraperitoneal or the intravenous administration of a mixture of plasmid DNA (100 microg) and ultrasound contrast agent microbubbles, an ultrasound transducer was applied on the abdominal wall. The reporter pTRE plasmid encoding Smad7 was used to evaluate transfection efficiency. Smad7 expression was induced by doxycycline in drinking water. We detected less than 10% apoptotic cells and no inflammatory reaction in peritoneal tissues following the ultrasound-microbubble-mediated transfection. More importantly, the insonation significantly improved the transfection efficiency in peritoneal tissues. The transfection efficiency by intraperitoneal delivery route was higher than the intravenous route. The reporter gene, pTRE-Smad7, was readily detected in the parietal peritoneum, mesentery, greater omentum and adipose tissue. The peak of transgene expression occurred 2 days after transfection and the transgene expression diminished in a time-dependent manner thereafter. Overall, the effectiveness and simplicity of the ultrasound-microbubble-mediated system may provide a promising nonviral means for improving gene delivery for treating peritoneal diseases in vivo.

A pilot study on tacrolimus treatment in membranous or quiescent lupus nephritis with proteinuria resistant to angiotensin inhibition or blockade.

Persistent proteinuria in patients with quiescent lupus can result from membranous lupus nephritis and/or glomerular scarring following previous flares. This pilot study examined the effects of tacrolimus over two years in six patients with membranous/inactive lupus nephritis and persistent proteinuria despite angiotensin inhibition/blockade. Tacrolimus treatment reduced proteinuria and increased serum albumin (time effect, P = 0.047 and 0.032 respectively). Compared with baseline levels, proteinuria improved by more than 50% in five patients (83.3%) and hypoalbuminaemia was corrected in four patients. The efficacy was most prominent in four patients with biopsy-proven membranous lupus nephritis, whose protienuria improved by over 80%. One patient developed biopsy-proven chronic nephrotoxicity after 10 months of tacrolimus treatment, despite non-excessive blood levels. These data suggest that tacrolimus is an effective treatment for proteinuria due to membranous lupus nephritis, but should probably be reserved for patients who are refractory to other non-nephrotoxic treatments, in view of the potential risk of subclinical nephrotoxicity.

Quality of life comparison between corticosteroid- and-mycofenolate mofetil and corticosteroid- and-oral cyclophosphamide in the treatment of severe lupus nephritis.

There is accumulating evidence that mycophenolate mofetil (MMF), when combined with corticosteroid, is an effective induction treatment for severe proliferative lupus nephritis and is associated with fewer adverse effects compared to cyclophosphamide (CTX), but the quality of life (QOL) associated with these regimens as perceived by the patient has not been compared. This study included patients who had experienced both treatment regimens, for distinct episodes of diffuse proliferative lupus nephritis. QOL parameters during the first six months of each treatment were assessed through SF36 and WHOQOL questionnaires. Twelve patients and 24 episodes of severe lupus nephritis were studied. CTX-treated and MMF-treated episodes showed comparable baseline characteristics and response rate, with complete remission occurring in 83.3%. MMF treatment was associated with higher numerical scores for all domains across both QOL instruments than CTX. MMF treatment was associated with significantly less fatigue, less impediment of physical and social functioning, and better psychological well being compared to CTX. When each patient served as her/his own control, most patients ascribed higher QOL domain scores to the MMF-treated episode. Seventy-five percent of patients found MMF treatment more acceptable and preferred when compared with CTX, and the complications that most concerned them included Cushingoid features, alopecia, menstrual disturbance and infections. These data showed that MMF-based induction immunosuppression for severe lupus nephritis was associated with better QOL than CTX as perceived by patients, which was most likely attributed to the reduced side-effects during MMF treatment.

A family-based association study of megsin A23167G polymorphism with susceptibility and progression of IgA nephropathy in a Chinese population.

AIMS: To investigate the association of megsin A23167G polymorphism with susceptibility and progression of IgA nephropathy in Chinese population. METHODS: 435 IgA nephropathy patients and their family members were recruited for a family-based association study. Genotypes of megsin A23167G were determined by direct sequencing. The results were analyzed by transmission disequilibrium test (TDT) and haplotype relative risk (HRR). Clinical data and histological scores of renal lesions were compared between patients with different genotypes. According to disease stability, IgA nephropathy patients were divided into progressive group and stable group. The distribution of genotype frequencies were compared between the 2 groups. RESULTS: TDT revealed that megsin 23167G alleles were transmitted more frequently from heterozygous parents to patients than expected (classical TDT: chi2 = 5.435, p = 0.020, extended TDT: chi2 = 5.017, p = 0.025). HRR analyses showed significant differences between transmitted and nontransmitted allele frequencies (chi2 = 7.006, p = 0.008, HRR = 1.762). The scores of glomerular index and glomerular sclerosis index were higher in GG genotype patients than those in other genotypes (F = 4.570, p = 0.033, F = 4.324, p = 0.038, respectively). The distribution frequency of GG genotype in the progressive group was higher than that of the stable group (chi2 = 4.370, p = 0.037). No statistical difference was found in tubulo-interstitial index, vascular index and clinical characteristics between the 2 groups. CONCLUSION: The polymorphism of megsin A23167G is associated with susceptibility and progression of IgA nephropathy in Chinese population. GG genotype is associated with severe histological lesions and progression of the disease.

Differential expression of receptors for advanced glycation end-products in peritoneal mesothelial cells exposed to glucose degradation products.

Autoclaving peritoneal dialysate fluid (PDF) degrades glucose into glucose degradation products (GDPs) that impair peritoneal mesothelial cell functions. While glycation processes leading to formation of advanced glycation end-products (AGE) were viewed commonly as being mediated by glucose present in the PDF, recent evidence indicates that certain GDPs are even more powerful inducers of AGE formation than glucose per se. In the present study, we examined the expression and modulation of AGE receptors on human peritoneal mesothelial cells (HPMC) cultured with GDPs, conventional PDF or PDF with low GDP content. HPMC cultured with GDPs differentially modulated AGE receptors (including RAGE, AGE-R1, AGE-R2 and AGE-R3) expression in a dose-dependent manner. At subtoxic concentrations, GDPs increased RAGE mRNA expression in HPMC. 2-furaldehyde (FurA), methylglyoxal (M-Glx) and 3,4-dideoxy-glucosone-3-Ene (3,4-DGE) increased the expression of AGE-R1 and RAGE, the receptors that are associated with toxic effects. These three GDPs up-regulated the AGE synthesis by cultured HPMC. In parallel, these GDPs also increased the expression of vascular endothelial growth factor (VEGF) in HPMC. PDF with lower GDP content exerted less cytotoxic effect than traditional heat-sterilized PDF. Both PDF preparations up-regulated the protein expression of RAGE and VEGF. However, the up-regulation of VEGF in HPMC following 24-h culture with conventional PDF was higher than values from HPMC cultured with PDF containing low GDP. We have demonstrated, for the first time, that in addition to RAGE, other AGE receptors including AGE-R1, AGE-R2 and AGE-R3 are expressed on HPMC. Different GDPs exert differential regulation on the expression of these receptors on HPMC. The interactions between GDPs and AGE receptors may bear biological relevance to the intraperitoneal homeostasis and membrane integrity.

Red blood cell alloantibodies and liver transplantation in Chinese patients.

BACKGROUND: Red blood cell (RBC) alloantibodies are present in up to 14% of white recipients of liver transplants and can cause severe delayed hemolysis. METHODS: A retrospective survey showed 17 cases (8.8%) of RBC alloantibodies in 192 consecutive Chinese recipients of liver transplants compared with a background hospital incidence of 3.7%. RESULTS: The spectrum of RBC alloantibodies in Chinese patients was different than in white patients, with no anti-D or anti-K antibodies but a significant incidence of anti-Mi (29%) antibodies. There was a significantly increased incidence of transfusions in RBC alloantibody positive cases. Delayed hemolysis also resulted in higher day-7 bilirubin levels. A total of 7 to 86 antigen-positive units were issued in five RBC alloantibody cases, including three early deaths. Seven cases in the RBC alloantibody negative group, but none in the positive group, were salvaged by regraft. CONCLUSIONS: Blood banks servicing transplant centers should be aware of ethnic patterns in RBC alloantibodies. Delayed hemolysis may jeopardize patient survival as the result of difficult postoperative stabilization, especially in cases requiring massive transfusion.

Red blood cell alloantibodies and liver transplantation in Chinese patients.

Red blood cell (RBC) alloantibodies are present in up to 14% of white recipients of liver transplants and can cause severe delayed hemolysis. A retrospective survey showed 17 cases (8.8%) of RBC alloantibodies in 192 consecutive Chinese recipients of liver transplants, compared with a 3.7% background hospital incidence. The spectrum of RBC alloantibodies was different from that in white recipients, with no anti-D or anti-K antibodies but with a significant incidence of anti-Mi (29%) antibodies. There was significantly increased transfusion in RBC alloantibody positive cases. Delayed hemolysis also resulted in higher day-7 bilirubin levels. A total of 7 to 86 antigen-positive units were issued in five RBC alloantibody cases, including three early deaths. Seven cases in the RBC alloantibody negative group, but none in the positive group, were salvaged by regraft. Blood banks servicing transplant centers should be aware of ethnic patterns in RBC alloantibodies. Delayed hemolysis may jeopardize patient survival as a result of difficult postoperative stabilization, especially in cases requiring massive transfusion.

Star fruit intoxication in uraemic patients: case series and review of the literature.

Star fruit, belonging to the Oxalidaceae family, species Averrhoa carambola, is a popular fruit among Orientals. There have been reports of hiccup, confusion, and occasional fatal outcomes in uraemic patients after ingestion of star fruit. An excitatory neurotoxin from star fruit has been implicated although the exact nature of this toxic substance has not been identified. A group of seven patients is described from the dialysis centres at Queen Mary and Tung Wah Hospitals who developed symptoms including hiccup, confusion, vomiting, impaired consciousness, muscle twitching and hyperkalaemia shortly after ingestion of star fruit. Symptoms of most patients resolved after intensified dialysis or spontaneously, and no mortality was observed. The close temporal relationship of ingestion of star fruit and onset of symptoms strongly suggests the existence of a causal relationship between the two. It is recommended that uraemic patients should totally abstain from star fruit due to these rare but potentially fatal complications. The clinical manifestations of other reported series and current evidence for the possible candidate(s) of the neurotoxin are discussed.

Reactivation of systemic lupus erythematosus in a dialysis patient after tuberculous peritonitis.

The disease activity of patients suffering from lupus nephritis usually becomes quiescent after the onset of end stage renal failure. Reactivation of lupus activity, especially after a long period of dialysis, is uncommon. Factors that might trigger off lupus reactivation after dialysis have not been well defined. We report a case of a 43-year-old Chinese woman on long-term peritoneal dialysis, who developed lupus reactivation with cerebral involvement 2 weeks after she was diagnosed to have tuberculous peritonitis. The close temporal relationship between the tuberculous peritonitis and the lupus reactivation raise the possibility that the tuberculous infection might have triggered off the lupus reactivation.