Cytomegalovirus glycoprotein-B vaccine with MF59 adjuvant in transplant recipients: a phase 2 randomised placebo-controlled trial.

BACKGROUND: Cytomegalovirus end-organ disease can be prevented by giving ganciclovir when viraemia is detected in allograft recipients. Values of viral load correlate with development of end-organ disease and are moderated by pre-existing natural immunity. Our aim was to determine whether vaccine-induced immunity could do likewise. METHODS: We undertook a phase-2 randomised placebo controlled trial in adults awaiting kidney or liver transplantation at the Royal Free Hospital, London, UK. Exclusion criteria were pregnancy, receipt of blood products (except albumin) in the previous 3 months, and simultaneous multiorgan transplantation. 70 patients seronegative and 70 seropositive for cytomegalovirus were randomly assigned from a scratch-off randomisation code in a 1:1 ratio to receive either cytomegalovirus glycoprotein-B vaccine with MF59 adjuvant or placebo, each given at baseline, 1 month and 6 months later. If a patient was transplanted, no further vaccinations were given and serial blood samples were tested for cytomegalovirus DNA by real-time quantitative PCR (rtqPCR). Any patient with one blood sample containing more than 3000 cytomegalovirus genomes per mL received ganciclovir until two consecutive undetectable cytomegalovirus DNA measurements. Safety and immunogenicity were coprimary endpoints and were assessed by intention to treat in patients who received at least one dose of vaccine or placebo. This trial is registered with ClinicalTrials.gov, NCT00299260. FINDINGS: 67 patients received vaccine and 73 placebo, all of whom were evaluable. Glycoprotein-B antibody titres were significantly increased in both seronegative (geometric mean titre 12,537 (95% CI 6593-23,840) versus 86 (63-118) in recipients of placebo recipients; p<0.0001) and seropositive (118,395; 64,503-217,272) versus 24,682 (17,909-34,017); p<0.0001) recipients of vaccine. In those who developed viraemia after transplantation, glycoprotein-B antibody titres correlated inversely with duration of viraemia (p=0.0022). In the seronegative patients with seropositive donors, the duration of viraemia (p=0.0480) and number of days of ganciclovir treatment (p=0.0287) were reduced in vaccine recipients. INTERPRETATION: Although cytomegalovirus disease occurs in the context of suppressed cell-mediated immunity post-transplantation, humoral immunity has a role in reduction of cytomegalovirus viraemia. Vaccines containing cytomegalovirus glycoprotein B merit further assessment in transplant recipients. FUNDING: National Institute of Allergy and Infectious Diseases, Grant R01AI051355 and Wellcome Trust, Grant 078332. SPONSOR: University College London (UCL).

Extensive human cytomegalovirus (HCMV) genomic DNA in the renal tubular epithelium early after renal transplantation: Relationship with HCMV DNAemia and long-term graft function.

Human cytomegalovirus (HCMV) infection is associated with a series of direct and indirect effects following renal transplantation. However, the presence of HCMV in the kidney and its relationship with acute rejection and long-term graft function remain to be fully elucidated. Sixty-two biopsies derived from 30 renal transplant recipients with signs of clinical rejection were analyzed for HCMV using a sensitive in situ DNA hybridization method. Biopsies were also subjected to staining with anti-C4d antibodies and an anti-caspase 3 antibody to detect humoral rejection and apoptosis, respectively. In 21 patients, serial serum creatinine levels over 5 years of follow-up were analyzed. HCMV DNA was detected in biopsies from 21/30 (70%) of the patients and 32/62 (52%) of the individual biopsies. HCMV DNA was detected early after transplant and was localized to renal tubule epithelial cells but not associated with apoptosis. HCMV DNAemia developed within 2 weeks of detecting HCMV DNA in the biopsy in 53% of patients. Ninety percent of patients experiencing HCMV disease had HCMV DNA in their biopsy. HCMV DNA was equally distributed between patients with or without histological evidence of acute rejection and was detected more frequently in patients with peritubular C4d deposits. Creatinine levels at 12 months post-transplant were significantly higher in patients with HCMV DNA and remained elevated over the 5 years of follow-up. HCMV DNA is frequently detected in renal tubular epithelial cells early after renal transplantation, precedes DNAemia and is associated with poor long-term graft function.

Effect of pamidronate on bone loss after kidney transplantation: a randomized trial.

BACKGROUND: Kidney transplantation is associated with an increased risk of bone fracture and rapid loss of bone mineral density after kidney transplantation. STUDY DESIGN: Randomized controlled trial. SETTING & PARTICIPANTS: Patients were randomly assigned to treatment (n = 46) or control (no treatment; n = 47) groups. Patients were stratified according to parathyroid hormone level and sex. Those with parathyroid hormone level less than 150 pg/mL were excluded. INTERVENTION: The treatment and control groups received pamidronate, 1 mg/kg, perioperatively and then at 1, 4, 8, and 12 months or no treatment, respectively. All received calcium (500 mg) and vitamin D (400 units) daily. Immunosuppression was cyclosporine and prednisolone, with no difference in dosing between the 2 groups. OUTCOMES & MEASUREMENTS: Bone mineral density was evaluated by means of dual-energy x-ray absorptiometry of the lumbar spine and hip at baseline and 3, 6, 12, and 24 months, with the primary end point at 1 year of percentage of change in bone mineral density from baseline. Clinical fractures were recorded and also evaluated by means of spinal radiographs at baseline and 1 and 2 years. RESULTS: Pamidronate protected bone mineral density at the lumbar spine; bone mineral density increased by 2.1% in the treatment group and decreased by 5.7% in the control group at 12 months (P = 0.001). Protection was also seen in Ward's area of the hip (P = 0.002) and the total hip (P = 0.004). There was no difference in femoral neck bone mineral density loss between the 2 groups. Fracture rates in the treatment and control groups were 3.3% and 6.4% per annum, respectively. LIMITATIONS: This study was not powered to detect differences in fracture rates. CONCLUSION: Pamidronate protects against posttransplantation bone loss at the lumbar spine and Ward's area of the hip.

Prospective monitoring of Epstein-Barr virus DNA in adult renal transplant recipients during the early posttransplant period: role of mycophenolate mofetil.

BACKGROUND: Epstein-Barr virus (EBV) is associated with posttransplant lymphoproliferative disease. We monitored the incidence of EBV viraemia in adult renal transplant recipients and investigated the association with clinical parameters. METHODS: Whole blood from 115 renal transplant patients was tested regularly by quantitative polymerase chain reaction (PCR) assay for EBV DNA during the first 90 days posttransplantation. RESULTS: Sixty four of 115 (56%) patients had detectable EBV DNA in blood (>100 copies/mL) on at least one occasion. The median time to first DNA detection was 15 days post-transplant and median viral load was 598 copies/mL (range 119-53,649 copies/mL). Multivariate Cox-regression analyses showed that patients receiving mycophenolate mofetil (MMF) on the day of transplant had a significantly lower risk of EBV viraemia compared to those who received no MMF (Hazard ratio=0.518, 95% CI 0.307-0.875, p=0.014). CONCLUSIONS: EBV viraemia is common during the early posttransplant period in adult renal transplant recipients. Our results suggest a role of MMF in preventing EBV viraemia, however further work is required to identify the mechanism(s) involved.

BK virus nephropathy in renal transplant patients in London.

BACKGROUND: BK nephropathy (BKN) is an important cause of renal transplant dysfunction, believed to be associated with higher levels of immunosuppression. We assessed the experience of BKN in renal transplant patients in the London region. METHODS: All six London transplant centers participated and case notes of patients with BKN in 2004 to 2005 were reviewed. RESULTS: There were 17 cases of BKN, giving an incidence of 2.1%. Median time to diagnosis was 9 months. Median baseline creatinine rose from 150 to 196 mumol/L. At diagnosis, 16 patients were on tacrolimus, 15 on mycophenolate mofetil, and 10 on triple therapy with tacrolimus, mycophenolate mofetil, and prednisolone. Management of BKN involved reducing immunosuppression; cidofovir was used in two patients and methylprednisolone in five for acute rejection. Median follow-up time was 29.2 months. Creatinine returned to baseline in four patients, remained elevated in 12 and one patient lost his graft. The new median baseline creatinine was 216 mumol/L. Eight patients underwent repeat biopsies of which four became negative for BKV and three subsequently cleared the virus on blood and urine polymerase chain reaction and urine decoy cells. Overall, eight patients cleared the virus. None of age, sex, viral load, or biopsy characteristics (Banff ct score, Drachenberg grade, and number of BKV positive cells) were associated with poorer outcome when patients with increase in creatinine of less than 30% (n=7) or more than 30% (n=10) from baseline were compared. CONCLUSION: The incidence of BKN in this study is comparable with previous studies, with more favorable outcomes. It supports the association of BKN with potent immunosuppression.

Late recurrent urinary tract infections may produce renal allograft scarring even in the absence of symptoms or vesicoureteric reflux.

BACKGROUND: The significance of late urinary tract infections (UTIs) after renal transplantation and their association with scarring and graft dysfunction remains controversial. We sought to define the prevalence of renal scarring in allograft recipients with a history of late recurrent UTIs, to determine whether the presence of vesicoureteric reflux (VUR) confers an increased risk of scarring and to establish whether scarring correlates with graft dysfunction. METHODS: Among 307 renal allograft recipients, we identified 56 (18%) with late recurrent UTIs (> or =3/year). A total of 32 patients had undergone further investigation by both 2,3 dimercapto-succinic acid single-photon emission computed tomography (99mTc-DMSA SPECT) scan and micturating cystourethrogram (MCUG). RESULTS: Of the 32 patients, 24 (75%) had scars on 99mTc-DMSA SPECT and 15 (47%) had reflux on MCUG. Thirteen of these 15 patients with reflux (87%) had scars, although there was no significant correlation between number of scars and degree of reflux. Eleven of 17 patients (65%) with UTIs but without VUR had scars, as did 12 of 14 (86%) with previous graft pyelonephritis. The pattern of scarring (typically multiple focal cortical defects) suggested infection as the cause. This pattern was not seen in a contemporary cohort with vascular occlusions and was rarely seen in patients with chronic allograft nephropathy. Scarring was not associated with inferior graft survival (median follow-up, 15 years). CONCLUSIONS: In patients with late UTIs, renal scarring is a frequent finding. Scarring may occur even in asymptomatic patients without VUR. The lack of an effect on graft survival may reflect successful intervention with prophylactic antibiotics and surveillance urine cultures. Late recurrent UTIs may be damaging to renal allografts, even in the absence of reflux.

Infection and cancer following renal transplantation.

Ever increasingly potent but non-specific immunosuppression has necessarily brought with it the continuing risk of opportunistic infections and virus-induced malignancies. The improvement in graft and patient survival rates from transplantation has depended to a certain extent on parallel improvements in the diagnosis and treatment of infectious complications. This review will highlight some of the current problems and progress. The risks of infection are largely related to the total burden of immunosuppression rather than any particular drug, although sirolimus and the anti CD25 antibodies may be an exception. Almost all the post-transplant infections are treatable; a precise microbiological diagnosis is essential so that specific therapy can be used. Newer molecular diagnostic techniques are increasingly widely available, e.g.quantitative polymerase chain reaction. The transplant community will inevitably be faced with highly resistant bacteria such as. Methicillin resistant Staphylococcus Aureus (MRSA) and will have to develop appropriate strategies. New infectious organisms continue to be identified [e.g. Burkitt's Virus (BKV), West Nile virus and Avian influenza) and will continue to tax the ingenuity of transplant physicians and microbiologists.

Modelling cytomegalovirus replication patterns in the human host: factors important for pathogenesis.

Human cytomegalovirus can cause a diverse range of diseases in different immunocompromised hosts. The pathogenic mechanisms underlying these diseases have not been fully elucidated, though the maximal viral load during infection is strongly correlated with the disease. However, concentrating on single viral load measures during infection ignores valuable information contained during the entire replication history up to the onset of disease. We use a statistical model that allows all viral load data sampled during infection to be analysed, and have applied it to four immunocompromised groups exhibiting five distinct cytomegalovirus-related diseases. The results show that for all diseases, peaks in viral load contribute less to disease progression than phases of low virus load with equal amount of viral turnover. The model accurately predicted the time of disease onset for fever, gastrointestinal disease and pneumonitis but not for hepatitis and retinitis, implying that other factors may be involved in the pathology of these diseases.

Prevention of contrast-induced nephropathy in vascular patients undergoing angiography: a randomized controlled trial of intravenous N-acetylcysteine.

OBJECTIVE(S): Apart from proper hydration, only oral N-acetylcysteine (NAC) has shown efficacy in reducing radiographic contrast media (RCM)-induced acute renal failure, though its benefit has been challenged. We investigated the effect of intravenous (i.v.) NAC on renal function in patients with vascular disease receiving RCM for angiography. METHODS: Single-center, randomized, double-blind, placebo-controlled trial. Based on a previous study, a trial with 44 patients each in placebo and treatment arms would give at least 80% power to show a statistically significant difference at the 5% level. Vascular patients undergoing angiography were consented and segregated into those whose serum creatinine (SC) level was normal or raised (men >1.32 mg/dl; women >1.07 mg/dL). All patients received 500 mL i.v. normal saline 6 to 12 hours prior to and then after angiography. Groups with normal SC and raised SC were randomly assigned to either 1 g of NAC with normal saline before and after angiography or nothing (placebo). Main outcome measures were change in SC and creatinine clearance (CrCl) as measured 1, 2, and 7 days postangiography (with comparison between active and placebo groups using unpaired t test) and incidence of acute renal decline (>25% or 0.5 mg/dL rise in SC) at 48 hours (with comparison between active and placebo using the Fisher exact test). RESULTS: Forty-six patients received NAC (29 normal SC, 17 raised SC), and 48 received placebo (27 normal SC, 21 raised SC). There was no significant difference in postangiography SC or CrCl at any of the time points measured between NAC and placebo in patients with either normal or raised SC. In the raised SC group, 3 patients from both the NAC and placebo groups suffered acute renal declines. Importantly, at 48 hours, the impaired SC group had a significant reduction in CrCl (-14% +/- 41% vs +18% +/- 58%: P = .0142) and a significant rise in SC (+7.0 +/- 25% vs -1.6% +/- 10%; P = .0246) when compared with the normal SC group. CONCLUSIONS: NAC (i.v. at 1 g) precontrast and postcontrast does not confer any benefit in preventing RCM-induced nephropathy in vascular patients. Patients with pre-existing raised SC have an increased risk of renal impairment as defined by a fall in CrCl and a rise in SC post-RCM when compared with patients with normal SC who appear to benefit from hydration.

Treatment of idiopathic membranoproliferative glomerulonephritis with mycophenolate mofetil and steroids.

BACKGROUND: Treatment of adults with idiopathic membranoproliferative glomerulonephritis (IMPGN) is often unrewarding with approximately 60% of patients progressing to end-stage renal failure within 10 years. Although children with IMPGN may respond to steroid therapy, there is no significant benefit to treating adult IMPGN patients with immunosuppression. METHODS: Outcome measures in five patients with IMPGN who were treated with oral prednisolone and mycophenolate mofetil (MMF) (treatment group) were compared with six patients with IMPGN who did not receive immunosuppression (control group). RESULTS: There was no significant difference between either group in baseline clinical characteristics or systolic and diastolic blood pressure during observation. In the treatment group, there was a significant reduction in proteinuria from a baseline of 5.09 to 1.97 g/24 h (P = 0.003) at 6 months, 1.96 g/24 h (P = 0.003) at 12 months and 2.59 g/24 h (P = 0.015) at 18 months. There was no significant change in proteinuria over 18 months in the control group. Serum creatinine concentration and creatinine clearance did not change significantly over 18 months in the treatment group. In the control group, there were significant changes in serum creatinine and creatinine clearance over 18 months [baseline 103 to 159 micromol/l (P = 0.004) and baseline 108 to 67 ml/min (P > 0.001), respectively] when compared to baseline, although the differences were not significant when the two groups were compared directly. CONCLUSIONS: This preliminary study suggests that in the short term, the combination of MMF and prednisolone can significantly reduce proteinuria and may preserve renal function in patients with IMPGN.

Acute transplant rejection induced by blood transfusion reaction to the Kidd blood group system.

Many renal transplant centres now try to avoid blood transfusion prior to renal transplantation, to avoid alloimmunization due to antibody production against donor antigens usually present on contaminating white cells. Post- or peri-operative transfusions are usually not considered to present problems, since the patient is heavily immunosuppressed. We present a patient who suffered a rare transfusion reaction, that we believe may have initiated a severe vascular rejection of a kidney transplant, probably mediated by Kidd blood group antigens.

A randomized, controlled trial comparing ganciclovir to ganciclovir plus foscarnet (each at half dose) for preemptive therapy of cytomegalovirus infection in transplant recipients.

Forty-eight patients who provided 2 consecutive blood samples that tested positive for cytomegalovirus DNA by polymerase chain reaction (PCR) were randomized to receive either full-dose ganciclovir (5 mg/kg intravenously [iv] twice daily) or half-dose ganciclovir (5 mg/kg iv once daily) plus half-dose foscarnet (90 mg/kg iv once daily) for 14 days. In the ganciclovir arm, 17 (71%) of 24 patients reached the primary end point of being CMV negative by PCR within 14 days of initiation of therapy, compared with 12 (50%) of 24 patients in the ganciclovir-plus-foscarnet arm (P = .12). Toxicity was greater in the combination-therapy arm. In patients who failed to reach the primary end point, baseline virus load was 0.77 log10 higher, the replication rate before therapy was faster (1.5 vs. 2.7 days), and the viral decay rate was slower (2.9 vs. 1.1 days) after therapy. Bivariable logistic regression models identified baseline virus load, bone-marrow transplantation, and doubling time and half-life of decay as the major factors affecting response to therapy within 14 days. This study did not support a synergistic effect of ganciclovir plus foscarnet in vivo.

Transjugular kidney biopsy.

BACKGROUND: Most previous studies demonstrating the feasibility of transjugular kidney biopsy have used a modified Colapinto aspiration biopsy needle. We present 25 high-risk patients, with contraindications to percutaneous renal biopsy, who underwent transjugular kidney biopsy using a transvenous side-cut needle. This technique is easier to learn and can be performed by an interventional radiologist with transjugular liver biopsy experience and equipment. The needle is designed for optimal cortical sampling but has a high incidence of capsular perforation. Elective coil embolization was used in selected patients to reduce the risk of bleeding. METHODS: We retrospectively reviewed the indications for obtaining renal histology, based on clinical presentation, and the specific indications for transjugular biopsy. Transjugular kidney biopsy was assessed for sampling effectiveness and adequacy, the impact of histology on patient management, and technique complication rates. RESULTS: Renal tissue was obtained in 23 cases, with diagnostic biopsies in 21 of 23 (91.3%). A mean of 3.5 cores were obtained with 9.9 glomeruli per procedure for light microscopy (range, 0 to 32), 2.2 (range, 1 to 7) for electron microscopy, and adequate tissue for immunoflorescence available in 11 of 23 biopsies. Histology influenced patient management in all 23 cases. Capsular perforation was recorded in 73.9% (17 of 23) of cases with 6 undergoing elective coil embolization. Two major complications occurred, both in patients with multiple risk factors for bleeding. One required coil embolization of an arterio-calyseal system fistula. A further patient developed renal vein thrombosis 6 days after a failed transjugular kidney biopsy. CONCLUSION: Transjugular kidney biopsy provides a histological diagnosis in high-risk patients, making an important contribution to patient management.