Cytomegalovirus infection in a seroendemic renal transplant population: a longitudinal study of virological markers

Post-transplant complications, patient, and graft survival in pediatric and adolescent kidney transplant recipients at a tropical tertiary care center across two immunosuppression eras

BACKGROUND

We report pediatric PAKT patient and graft outcomes at a large tropical tertiary center spanning two transplant eras.

METHODS

In this retrospective cohort study, all children ≤18 years who underwent kidney transplantation at our center between 1991 and 2016 were included. Data pertaining to their baseline characteristics, post-transplant events, and outcome were retrieved from transplant records and compared between transplant eras (1991-2005 and 2006-2016).

RESULTS

A total of 139 children (mean age 15.2 ± 2.9 years) underwent PAKT during this period. The incidence of UTIs, CMV disease, BKVN, invasive fungal infections, new-onset diabetes after transplant, leucopenia, and recurrent NKD was higher in the 2006-2016 era (P < .001 for all), while 1-year cumulative BPAR was comparable (P = .100). Five-year graft and patient survival in the two eras were 89.9% and 94.2% (P = .365) and 92.1% and 95.3% (P = .739), respectively. Incidence of CMV disease, BKVN, graft loss, and death was lower in the calcineurin withdrawal group. Non-adherence accounted for 36% of graft loss; infections caused 43.7% of deaths. On multivariate Cox proportional hazards analysis, independent predictors for graft loss were UTIs and blood transfusion naïve status and for death were serious infections and glomerular NKD.

CONCLUSIONS

PAKT in India has excellent long-term graft outcomes, though patient outcomes remain suboptimal owing to a high burden of infections. Current immunosuppression protocols need to be re-examined to balance infection risk, graft, and patient survival.

Seroprevalence of cytomegalovirus in donors & opportunistic viral infections in liver transplant recipients

Background & objectives:

Opportunistic virus infections are common in liver transplant (LT) recipients. There is a risk of developing infection with cytomegalovirus (CMV) and herpes-related viruses such as herpes simplex virus-1 and 2 (HSV-1 & 2), Epstein-Barr virus (EBV) and Varicella Zoster virus (VZV), reactivation of infection and recurrent infection. This study was conducted to determine CMV seropositivity in donors and its influence on LT recipients and seropositivity of CMV, HSV-1 and 2, EB viral capsid antigen (EBVCA) and VZV in LT recipients and their reactivation.

Methods:

Pre-transplant data for IgG and IgM for CMV (and donor), HSV-1 and -2, EB viral capsid antigen (VCA) and VZV were available for 153 recipients. All recipients were on ganciclovir or valganciclovir prophylaxis for three months after LT. For reactivation rates, findings of post-transplant CMV quantitative reverse transcription polymerase chain reaction (CMV qRT-PCR) assay were associated with pre-transplant serological profile.

Results:

Of the 153 LT recipients, 131 were men (85.6%). The median age of LT was 46 yr (range 9 months-71 yr). Overall exposure to CMV was 71.8 per cent followed by EB VCA (61.4%) and VZV (49.6%). Susceptibility to both HSV-1 and -2 was high across all decades (P<0.001). Seropositivity of CMV in donor was 90.9 per cent (100 out of 110). Post-transplant CMV qRT- PCR was positive in 17 (26.6%; 3 in recipient negative) of 64 samples tested. qRT-PCR assay was positive in one out of four (25%) tested for HSV-1 and nine out of 19 (47.4%) tested for EBV. Two recipients tested for HSV-2 and one for VZV were negative. There were three deaths in recipients (D+ R+) who were also positive for CMV qRT PCR. There was one death due to HSV-1 pneumonia. One patient with EBV reactivation developed post-transplant lymphoproliferative disorder two years after transplant.

Interpretation & conclusions:

Transplant recipient were at highest risk of acquiring HSV-1 and -2 more so for HSV-2. CMV exposure in transplant recipients and donors were very high and at greatest risk for recipient reactivation rate. Despite this, death related to CMV reactivation was low.

Leflunomide for cytomegalovirus: bench to bedside

Cytomegalovirus (CMV) remains a major cause of morbidity and mortality among transplant recipients, frequently engaging the clinician in a struggle to balance graft preservation with control of CMV disease. Leflunomide has been shown to have immunosuppressive activity in experimental allograft models together with antiviral activity inhibiting CMV both in vitro and in vivo. Data are emerging about its potential role in ganciclovir-sensitive and -resistant CMV, primarily by virtue of a unique mechanism inhibiting virion assembly, as opposed to inhibition of viral DNA synthesis by current agents. This review aims to put in perspective, the knowledge acquired in the last decade or so on leflunomide for CMV. Evidence suggests that it might have activity against human CMV with good oral bioavailability and, more importantly in the resource-poor setting, is economical. Although the data presented here are not from randomized trials, several relevant observations have been made that could influence future, more structured assessments of the drug. An immune suppressive compound with antiviral features and experimental activity in chronic rejection is an attractive combination for organ transplantation, and it appears that leflunomide may just fit that niche.

"pp65 antigenemia and real time polymerase chain reaction (PCR) based-study to determine the prevalence of human cytomegalovirus (HCMV) in kidney donors and recipients with follow-up studies"

Background

The present study was undertaken to determine the rate of occurrence of Human cytomegalovirus (HCMV) among kidney transplant recipients and donors by application of direct detection methods and to understand HCMV infection/disease development among transplanted patients as a prospective study.

Results

Peripheral blood samples collected from 76 kidney donors and 76 recipients from September 2007 to August 2009 were subjected to pp65 antigenemia and Quantitative real-time PCR (qRT-PCR) assays. Data were analyzed under Group A, B and C. Group A was further divided into sub-groups I, II, III, IV, and V for better understanding. Three, one and two donors in sub-group I, III, IV of Group A tested positive for real time PCR respectively. One recipient from group III tested positive for HCMV by qRT- PCR prior transplantation and remained positive one month post-transplantation. Three other recipients, tested negative prior to transplantation became positive a month after transplantation. Group B consisted of 18 donor-recipient pairs and one of the donor tested positive for HCMV by qRT-PCR. Eight recipients tested positive for HCMV one month after transplantation. The pp65 positivity and HCMV DNA load was high among group C recipients who mostly had symptoms of active disease. Significantly high values of pp65 antigenemia were observed among recipients of sub-group II (non-parametric chi-square test p = 0.007). Positive correlation between pp65 antigenemia and qRT-PCR value was observed. Thirty three of the recipients with disease treated with Valgancyclovir showed improved clinical outcome.

Conclusion

Our study showed that a significant proportion of kidney recipients develop HCMV infection following renal transplantation in spite of the absence of HCMV among donors. pp65 antigenemia assay and qRT- PCR methods can be applied to detect HCMV among kidney donors and recipients to monitor development of disease and these assays were predicative of HCMV infection among them. Clinical resistant to valganciclovir was not observed.

Outcome of pediatric renal transplantation in north India

We report our experience and long-term outcome of pediatric renal transplantation at a referral center in New Delhi. During 1995-2008, 45 transplants were performed in 43 patients at a mean age of 13.3 ± 4.0 (range 3.8-18) yr. The chief causes for ESRD were reflux nephropathy, obstructive uropathy, vasculitis, renal dysplasia, and focal segmental glomerulosclerosis. Most (91.1%) donors were living related. Post-transplant immunosuppression comprised prednisolone, a calcineurin inhibitor and azathioprine or MMF. AR and CR were seen in 14 (31.1%) and 12 (26.7%) allografts, respectively. Predictors of CR were unsatisfactory compliance and multiple episodes of AR (p = 0.002 each). Urinary infections (n = 13), septicemia (4), tuberculosis (4), CMV disease (7), viral hepatitis (7), and pneumonia (3) were important causes of morbidity. Two patients each had lymphoproliferative disease and new-onset diabetes. There were eight (17.8%) graft losses and six (14%) deaths. The one-, five- and 10-yr graft survivals were 91.1%, 80.4% and 75.1%, respectively; the mean graft survival was 119.4 ± 8.38 months. The respective patient survivals were 95.3%, 87.9%, and 76.9% at one-, five- and 10 yr. Our results affirm that despite scarcity of resources and frequent infections, long-term outcomes of pediatric renal transplantation are highly satisfactory.

Dysregulated cytokine responses during cytomegalovirus infection in renal transplant recipients

OBJECTIVE

Pre- and posttransplant predisposing factors for cytomegalovirus (CMV) activation and disease are not well defined. The aim of this study was to examine whether there are differences in plasma cytokine levels pretransplant, before and during CMV replication in renal transplant recipients.

MATERIAL AND METHODS

We studied 76 renal transplant recipients in whom CMV-DNA was studied at regular intervals posttransplant. Thirty-eight patients developed CMV viremia posttransplant (CMV-DNA-positive). Thirty-eight patients had no detectable CMV-DNA posttransplant (CMV-DNA-negative). Cytokine and cytokine receptors/antagonists plasma levels were measured pretransplant, and pre-, during, and after CMV-viremia in CMV-DNA-positive patients and at similar time points in CMV-DNA-negative transplant recipients.

RESULTS

Compared with pretransplant, after transplantation soluble (s) plasma interleukin (IL)-2 receptor (R), IL-6, and interferon-gamma (IFN-gamma) decreased in both groups (CMV-DNA-positive: P=0.002; P=0.028; P=0.032; CMV-DNA-negative: P=0.001; P=0.040; P=0.030) whereas IL-10 remained constant in both groups (P=n.s.). During CMV viremia, sIL-2R (P=0.015) and IL-6 (P=0.006) increased compared with previremia but remained constant in CMV-DNA-negative patients matched for the day of investigation (P=n.s.). Simultaneously, IFN-gamma increased in CMV-DNA-negative patients (P=0.008) and remained constant in CMV-DNA-positive patients (P=n.s.). During CMV viremia, IL-10 (P=0.002) and sIL-2R (P=0.007) were significantly higher in CMV-DNA-positive than CMV-DNA-negative patients investigated at similar time points.

CONCLUSION

Our results indicate that CMV replication in renal transplant recipients is associated with increased sIL-2R, IL-6, and IL-10 and decreased IFN-gamma plasma levels, pointing to a monocyte/Th2 activation and a Th1 blockade. The high IL-10 might decrease the IFN-gamma plasma levels in CMV-DNA-positive patients. Th1 deficiency in CMV-DNA-positive patients might promote development of CMV disease.

Pediatric renal transplantation--a single center experience of 15 yr from India

Renal transplantation is the optimal treatment for children with ESRD. We undertook this study to establish the outcome of pediatric renal transplants in a resource-constrained environment in a developing country. A retrospective analysis on 90 pediatric renal transplants (age at transplant </=18 yr) done at our center over a 15 yr period was analyzed. The mean age of the recipients was 15 yr (range 6-18 yr) accounting for 6.1% of all the renal transplants done at our center (90/1472). Ninety-six percent of patients received kidneys from live-related donors. The major causes of ESRD were glomerulonephritis (28%) and urological abnormalities (17%), while the etiology was unknown in 50%. Immunosuppression was based on a triple drug regimen consisting of prednisolone, CsA and azathioprine in 98% of children. Amongst complications, any acute rejection episodes (46.7%), UTI (26.7%) and CMV disease (16.7%) predominated. The mean duration of follow-up was 42 +/- 33 month (range 3-159 month). Graft loss occurred in nine (10%) children at a mean duration of 25 +/- 22 month (range 6-70 month). Overall 1-, 5-, and 10-yr graft survival was 98%, 84% and 76%. Overall 1-, 5-, and 10-yr patient survival was 95%, 87%, and 79%. The significant predictors of graft loss were CMV disease (p = 0.018) and >2 rejection episodes (p = 0.05), while sepsis (p = 0.01) was the most important contributor to patient loss. Pediatric renal transplantation in India can be accomplished successfully. The graft and patient survival in our study, the largest from India, is comparable to those published from developed countries and is encouraging given the limited resources.

Donor and recipient CMV serostatus and antigenemia after renal transplantation: an analysis of 486 patients

BACKGROUND

Cytomegalovirus infection in renal transplant recipients is a major clinical problem, with both short and long term sequelae. Infection can occur as a result of reactivation of latent virus or new infection from donor tissues. The impact of donor and recipient serostatus on viremia is well recognised, with seronegative recipients at greatest risk after transplantation of an organ from a seropositive donor. However, the impact of grafting such organs into seropositive recipients is less clear.

OBJECTIVES

To assess the impact of recipient serostatus on the risk of CMV antigenemia in a large renal transplant cohort.

STUDY DESIGN

We prospectively quantified CMV antigenemia over time in a cohort of 486 recipients. We analysed the antigenemia status according to donor and recipient serostatus.

RESULTS

Antigenemia was most common in seronegative recipients of organs from seropositive donors (D+/R-). Nevertheless, we observed that even in CMV seropositive recipients, the impact of donor serostatus on CMV antigenemia is still substantial (p=0.006; OR=2.2).

CONCLUSIONS

In this large study, donor serostatus clearly plays a significant role in determining CMV risk, even in seropositive recipients.

Acute graft pyelonephritis following renal transplantation

BACKGROUND

Urinary tract infection is the most common form of bacterial infection encountered in a renal transplant recipient. Studies explaining the long-term consequences of acute graft pyelonephritis (AGPN) are few.

METHODS

A total of 1022 consecutive renal allograft recipients were studied retrospectively over a period of 10 years for evidence of AGPN. These patients were classified into two groups according to the presence or absence of at least one AGPN episode. Only culture-proven infections were included in the study.

RESULT

Of the 1022 renal transplant recipients, 169 patients (16.5%) developed AGPN. In the multivariate analysis with stepwise logistic regression, significant associations were observed between AGPN and placement of ureteric stent (odds ratio [OR]=4.6), urological malformations of native kidney (OR=2.1), cytomegalovirus (CMV) disease (OR=2.0), mycophenolate mofetil (MMF)-based regimen (OR=1.9), and acute rejection episodes (OR=1.5). However, age>40 years, female gender, induction therapy, anti-CD3 treatment, and hyperglycemia did not show such an association. In comparison with the non-AGPN group, these patients had a lower graft and patient survival (though it did not attain statistical significance). In the multivariate analysis using the Cox model for the entire study population, AGPN did not independently contribute to poor graft or patient survival.

CONCLUSION

AGPN in the renal transplant setting is an ominous event, as these patients are also more prone to develop bacteremia, acute rejection, and CMV disease, which could then lead to poor graft and patient survival. Its association with MMF needs further clarification.

A Prospective Evaluation of Leflunomide Therapy for Cytomegalovirus Disease in Renal Transplant Recipients

AIM

A preliminary observation suggests leflunomide is effective in the treatment of cytomegalovirus (CMV) disease in renal transplant recipients. A prospective evaluation was conducted in renal transplant recipients to study the efficacy of leflunomide in the treatment of CMV disease.

PATIENTS AND METHODS

With prior approval and informed consent for therapy and follow-up, 17 consecutive consenting renal transplant recipients with proven CMV disease were treated with leflunomide. CMV disease was defined as a clinical syndrome of fever and/or symptoms of organ involvement, leukopenia, and a positive nested CMV quantitative PCR test at 0.001 microg/5 microL template input, with or without histologic evidence of tissue invasion. Leflunomide metabolite concentrations (A77 1726) were monitored.

RESULTS

Of the 17 patients, 14 patients were treated for 6 months for CMV disease the first time; the remaining 3 received leflunomide treatment for relapse after ganciclovir treatment, for a year. Seven patients had fever with viremia and no organ involvement, nine had viremia with involvement of gastrointestinal tract, and one had fever with CMV inclusions in the allograft, with no demonstrable viremia. The three patients with relapse treated with leflunomide responded. Overall, 15 patients (88%) clinically responded to leflunomide therapy and with viral clearance from blood and healing of involved organs. The cost of therapy with intravenous ganciclovir (Cymevene, Roche) for 2 weeks was US 721 dollars while that of leflunomide (Cleft, Cipla Ltd) for 6 months was US 64 dollars.

CONCLUSION

Leflunomide treatment for CMV disease in renal transplant recipients is effective, simple, and economical.

Therapeutic implication of quantitative pp65 antigen assay in living renal transplant in a high seroendemic population

Various methods have been used to diagnose cytomegalovirus (CMV) infection/disease; however, pp65 antigenemia assay has emerged as a good marker for CMV disease in a high seroendemic population. We studied the role of quantitative pp65 antigen assay in live related renal transplant recipients in a high seroendemic population. Between November 1998 and May 2003, a total of 350 blood samples from 250 symptomatic patients were tested by quantitative pp65 antigen assay; 14% of the patients tested positive. There were 5 (14%) low-positive and 30 (86%) high-positive patients. All high-positive patients had CMV disease. The response to antiviral therapy monitored by the assay was dramatic, and one low-positive patient responded to reduction in immunosuppression. In conclusion, pp65 antigen assay is a good test for diagnosing CMV disease and monitoring response to antiviral therapy in a high seroendemic population.

LEFLUNOMIDE THERAPY FOR CYTOMEGALOVIRUS DISEASE IN RENAL ALLOGRAFT RECEPIENTS

Leflunomide has excellent antiviral activity against cytomegalovirus (CMV) in animal models and is considerably less expensive than intravenous ganciclovir. We used leflunomide in four consenting renal allograft recipients with symptomatic CMV disease, who were unable to afford ganciclovir and would otherwise remain untreated. This is the first report of efficacy of leflunomide in humans with CMV disease. They received loading dose of 100 mg of leflunomide once daily on days 1-3 and then 20 mg once daily for 3 months. All four patients were followed up three times weekly with physical examination, total leukocyte counts, blood urea and serum creatinine for a minimum period of 6 weeks. None of the patients showed drug related adverse events, alteration in cyclosporine levels, or decreased graft function, except one who developed leucopenia. Preliminary data presented suggests that leflunomide therapy for CMV disease is effective and could be used with careful monitoring in allograft recipients who cannot afford intravenous ganciclovir therapy. The duration of treatment and the role of leflunomide in secondary prophylaxis and in situations of ganciclovir resistance need to be studied further.

Posttransplant infections in the tropical countries

Over half of all renal transplant recipients in the tropical countries develop a serious infection at some point in the posttransplant period and 20% to 40% of them succumb to these infections. Many of these infections are endemic to the region. A multitude of factors including unhygienic conditions, hot and humid climate, late presentation, lack of knowledge about the spectrum of organisms in these areas, scanty diagnostic techniques, and high cost of lifesaving antimicrobial agents contribute to this dismal outcome. Tuberculosis is observed in 10% to 15% of transplant recipients. Pleuropulmonary disease is most frequent, but the commonly employed tests are seldom helpful in the diagnosis. Bronchoalveolar lavage is very sensitive in early detection of this infection and allows timely institution of specific therapy. Hepatitis virus infections are generally acquired before transplant, and viral replication is accelerated under the effect of immunosuppressive therapy leading to chronic liver disease. Cytomegalovirus (CMV) disease has shown a fourfold increase after introduction of cyclosporine to the immunosuppressive regimes at our center. Coinfection with other bacteria or fungi is frequent in CMV-infected allograft recipients. Opportunistic fungal infections are seen in less than 10% of allograft recipients, but this figure is likely an underestimate. The frequently encountered fungal infections include Candida, Aspergillus, Cryptococcus, and Mucor. Fungal infections carried a high mortality of over 65% at our center. The protean manifestations of the opportunistic infections and nonavailability of sensitive diagnostic tests in most centers in the underdeveloped countries often delay the diagnosis and institution of therapy.