BK polyomavirus (BKV) is an important cause of graft loss in renal transplant recipients that continues to pose a significant challenge to clinicians due to its frequently unpredictable onset, ...persistence, and the lack of effective antiviral agents or prevention strategies. This review covers our current understanding of epidemiology, viral transmission and disease progression, and treatment and prevention strategies that have been used to manage this disease.
Summary 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).
There are over 12,000 people with sickle cell disease (SCD) in the UK, and 4-12% of patients who develop Sickle Cell Nephropathy (SCN) progress to End Stage Renal Disease (ESRD). Renal ...transplantation offers the best outcomes for these patients with but their access to transplantation is often limited. Regular automated exchange blood transfusions (EBT) reduce the complications of SCD and may improve outcomes. However, concerns over alloimmunisation limit its widespread implementation. In this retrospective multicenter study, data were collected on 34 SCD patients who received a kidney transplant across 6 London Hospitals between 1997 and 2017. 20/34 patients were on an EBT program, pre or post renal transplantation. Overall patient and graft survival were inferior to contemporaneous UK data in the ESRD population as a whole, a finding which is well-recognised. However, patient survival (CI 95%, p = 0.0032), graft survival and graft function were superior at all time-points in those who received EBT versus those who did not. 4/20 patients (20%) on EBT developed de novo donor specific antibodies (DSAs). 3/14 patients (21%) not on EBT developed de novo DSAs. The incidence of rejection in those on EBT was 5/18 (28%), as compared with 7/13 (54%) not on EBT. In conclusion, our data, while limited by an inevitably small sample size and differences in the date of transplantation, do suggest that long-term automated EBT post renal transplant is effective and safe, with improvement in graft and patient outcomes and no increase in antibody formation or graft rejection.
Human cytomegalovirus (HCMV) can be managed by monitoring HCMV DNA in the blood and giving valganciclovir when viral load exceeds a defined value. We hypothesised that such pre-emptive therapy should ...occur earlier than the standard 3000 genomes/ml (2520 IU/ml) when a seropositive donor transmitted virus to a seronegative recipient (D+R-) following solid organ transplantation (SOT).
Our local protocol was changed so that D+R- SOT patients commenced valganciclovir once the viral load exceeded 200 genomes/ml; 168 IU/ml (new protocol). The decision point remained at 3000 genomes/ml (old protocol) for the other two patient subgroups (D+R+, D-R+). Virological outcomes were assessed three years later, when 74 D+R- patients treated under the old protocol could be compared with 67 treated afterwards. The primary outcomes were changes in peak viral load, duration of viraemia and duration of treatment in the D+R- group. The secondary outcome was the proportion of D+R- patients who developed subsequent viraemia episodes.
In the D+R- patients, the median values of peak viral load (30,774 to 11,135 genomes/ml, p<0.0215) were significantly reduced on the new protocol compared to the old, but the duration of viraemia and duration of treatment were not. Early treatment increased subsequent episodes of viraemia from 33/58 (57%) to 36/49 (73%) of patients (p< 0.0743) with a significant increase (p = 0.0072) in those episodes that required treatment (16/58; 27% versus 26/49; 53%). Median peak viral load increased significantly (2,103 to 3,934 genomes/ml, p<0.0249) in the D+R+ but not in the D-R+ patient subgroups. There was no change in duration of viraemia or duration of treatment for any patient subgroup.
Pre-emptive therapy initiated at the first sign of viraemia post-transplant significantly reduced the peak viral load but increased later episodes of viraemia, consistent with the hypothesis of reduced antigenic stimulation of the immune system.
To help decide when to start and when to stop pre-emptive therapy for cytomegalovirus infection, we conducted two open-label randomized controlled trials in renal, liver and bone marrow transplant ...recipients in a single centre where pre-emptive therapy is indicated if viraemia exceeds 3000 genomes/ml (2520 IU/ml) of whole blood.
Patients with two consecutive viraemia episodes each below 3000 genomes/ml were randomized to continue monitoring or to immediate treatment (Part A). A separate group of patients with viral load greater than 3000 genomes/ml was randomized to stop pre-emptive therapy when two consecutive levels less than 200 genomes/ml (168 IU/ml) or less than 3000 genomes/ml were obtained (Part B). For both parts, the primary endpoint was the occurrence of a separate episode of viraemia requiring treatment because it was greater than 3000 genomes/ml.
In Part A, the primary endpoint was not significantly different between the two arms; 18/32 (56%) in the monitor arm had viraemia greater than 3000 genomes/ml compared to 10/27 (37%) in the immediate treatment arm (p = 0.193). However, the time to developing an episode of viraemia greater than 3000 genomes/ml was significantly delayed among those randomized to immediate treatment (p = 0.022). In Part B, the primary endpoint was not significantly different between the two arms; 19/55 (35%) in the less than 200 genomes/ml arm subsequently had viraemia greater than 3000 genomes/ml compared to 23/51 (45%) among those randomized to stop treatment in the less than 3000 genomes/ml arm (p = 0.322). However, the duration of antiviral treatment was significantly shorter (p = 0.0012) in those randomized to stop treatment when viraemia was less than 3000 genomes/ml.
The results illustrate that patients have continuing risks for CMV infection with limited time available for intervention. We see no need to alter current rules for stopping or starting pre-emptive therapy.
Up to one third of patients on renal replacement programmes have an unknown cause of kidney disease, and the diagnosis may only be established following renal transplantation when the disease recurs ...or if new extra-renal symptoms develop.
We present two patients who presented with progressive chronic kidney disease of unknown cause. Both patients underwent successful renal transplantation but subsequently developed multisystem abnormalities, and were ultimately diagnosed with mitochondrial cytopathy 10-15 years following transplantation.
Mitochondrial cytopathies are rare inborn errors of metabolism that should be considered in adults with renal impairment, especially in those with a family history of kidney or other multisystem disease. The widespread availability of genetic testing provides the potential for earlier diagnoses, thereby enhancing management decisions, anticipation of complications, avoidance of mitotoxic drugs, and informed prognosis prediction.
Posttransplant lymphoproliferative disease is a complication of organ transplant with a myriad clinical and anatomic manifestations, thus making diagnosis difficult without histologic confirmation. ...In cases of lymphadenopathy confined to the abdomen, the diagnosis can be delayed because of late presentation and difficulty obtaining a tissue for histologic analyses. We describe the use of cross-sectional nuclear medicine imaging to locate enlarged abdominal lymph nodes; this facilitated minimally invasive laparoscopic lymph node excision biopsy to rapidly diagnose 2 cases of post-transplant lymphoproliferative disease. Prompt diagnosis has enabled early effective treatment, resulting in good patient outcomes.
Cytomegalovirus (CMV) is one of opportunistic infections post solid organ transplant and remains a cause of morbidity and mortality. Mammalian target of rapamycin inhibitors has a theoretical ...antiviral advantage compared to conventional immunosuppression. The primary outcome was to assess the viremic response and kidney function in a cohort of kidney transplant recipients (KTRs) with difficult to manage CMV infection when converted to sirolimus. We retrospectively analyzed the outcome of substituting sirolimus for mycophenolate mofetil (MMF) or tacrolimus in 18 KTR with difficult to manage, resistant/recurrent CMV viremia unresponsive or intolerant of standard anti-CMV treatment, or immunosuppression reduction. Safety and feasibility of sirolimus conversion were assessed through studying CMV viral loads, creatinine levels, immunosuppression, antiviral therapy, kidney function, and acute rejection episodes before and after starting sirolimus as well as the sirolimus side effects. Data were collected from the hospital filing system. The Wilcoxon matched-pairs signed-rank test and Friedman test were used for statistical analysis. The area under the curve for Log10 CMV viral load (log10 copies/ml) was significantly higher before than after the sirolimus switch (P = 0.0156). The median number of days on antiviral treatment was reduced after conversion to sirolimus 48 days (0-95); vs. 68 days (21-146). Acute rejection occurred more commonly before than after starting sirolimus n =5 (27.7%) vs. n = 2 (11.1%). Median serum creatinine before conversion to sirolimus was 175.5 μmol/L (79-243), and showed no deterioration three months and one year after conversion 148 (69-271) and 162.5 (69-287) μmol/L, respectively, P = 0.002. The use of sirolimus, often alongside tacrolimus and after discontinuation of MMF, is a useful strategy in treating recurrent CMV viremia without provoking rejection.
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