Incidence, risk factors, and outcomes associated with cytomegalovirus disease in small bowel transplant recipients

Cytomegalovirus Infection Management in Multivisceral and Intestinal Transplant: A Dual Institution Study

Intestinal transplant and multivisceral transplant were originally in pediatric populations and are relatively new procedures in adults. Despite increasing success rates in the immediate post-transplant period, infectious complications and acute and chronic rejection remain significant causes of morbidity and mortality. Previous research has shown cytomegalovirus (CMV) is the main cause of infection in this population. Due to the limited patient population, incidence of CMV viremia ranges widely and there is lack of universal protocol for treatment. This dual institution retrospective chart review between Henry Ford Hospital and Duke University analyzed adult intestinal and multivisceral transplant recipients between 2009 and 2019. Of the 32 patients identified and included in the study, 15 had CMV infection (46.9%). Of those with CMV infection, 5 (33.3%) had donor positive (D+)/recipient positive (R+) status; 5 had D-/R+; 4 had D+/R-; and one had D-/R-. There was no significant difference between mortality in those who had reported infection and not (80% vs 76.5%). The data from this study show significant rates of CMV viremia in patients undergoing intestinal transplant/multivisceral transplant with almost half of our study population having documented infection within 1 year of transplant, stressing the importance for universal protocol into CMV viremia treatment.

A Case Report of Successful Use of Twice-Daily Letermovir in the Treatment of Resistant Cytomegalovirus in a Small Bowel Transplant Recipient

Cytomegalovirus (CMV) is considered one of the most notable pathogens that affect patients after solid organ transplantation (SOT), especially small bowel transplant patients with a risk of high mortality rate. Its management relies historically on the use of CMV DNA polymerase inhibitors (namely, ganciclovir and valganciclovir). Second-line options include foscarnet and cidofovir, which are highly nephrotoxic and thus less preferred and only used in ganciclovir intolerance or resistance cases. Letermovir is a novel antiviral agent approved for CMV prophylaxis in hematopoietic stem cell transplant, but not for SOT (neither for prophylaxis nor for treatment). We report the first case on the successful use of letermovir in treating CMV disease in a small bowel transplant patient who failed to achieve viral clearance due to ganciclovir resistance and severe intolerance to foscarnet.

Pediatric intestinal transplantation

Advancements in donor management, organ preservation and operative techniques, as well as immunosuppressive therapies, have provided children with intestinal failure and its complications a chance not only for enteral autonomy but also long-term survival through intestinal transplantation (ITx). First described in the 1960's, experience has grown in managing these complex patients both pre- and post-transplant. The goals of this review are to provide a brief history of intestinal transplantation and intestinal rehabilitation in pediatric patients, followed by focused discussions of the indications for ITx, induction and maintenance immunosuppression therapies, common post-operative complications, and outcomes/quality of life post-transplant.

Use of Viral Load as a Surrogate Marker in Clinical Studies of Cytomegalovirus in Solid Organ Transplantation: A Systematic Review and Meta-analysis

Symptomatic cytomegalovirus (CMV) disease has been the standard endpoint for clinical trials in organ transplant recipients. Viral load may be a more relevant endpoint due to low frequency of disease. We performed a meta-analysis and systematic review of the literature. We found several lines of evidence to support the validity of viral load as an appropriate surrogate end-point, including the following: (1) viral loads in CMV disease are significantly greater than in asymptomatic viremia (odds ratio, 9.3 95% confidence interval, 4.6-19.3); (2) kinetics of viral replication are strongly associated with progression to disease; (3) pooled incidence of CMV viremia and disease is significantly lower during prophylaxis compared with the full patient follow-up period (viremia incidence: 3.2% vs 34.3%; P < .001) (disease incidence: 1.1% vs 13.0%; P < .001); (4) treatment of viremia prevented disease; and (5) viral load decline correlated with symptom resolution. Based on the analysis, we conclude that CMV load is an appropriate surrogate endpoint for CMV trials in organ transplant recipients.

The Third International Consensus Guidelines on the Management of Cytomegalovirus in Solid-organ Transplantation. Transplantation. 2018;102:900-931. [PMID: 29596116 DOI: 10.1097/tp.0000000000002191]

Despite recent advances, cytomegalovirus (CMV) infections remain one of the most common complications affecting solid organ transplant recipients, conveying higher risks of complications, graft loss, morbidity, and mortality. Research in the field and development of prior consensus guidelines supported by The Transplantation Society has allowed a more standardized approach to CMV management. An international multidisciplinary panel of experts was convened to expand and revise evidence and expert opinion-based consensus guidelines on CMV management including prevention, treatment, diagnostics, immunology, drug resistance, and pediatric issues. Highlights include advances in molecular and immunologic diagnostics, improved understanding of diagnostic thresholds, optimized methods of prevention, advances in the use of novel antiviral therapies and certain immunosuppressive agents, and more savvy approaches to treatment resistant/refractory disease. The following report summarizes the updated recommendations.

Prevention and Treatment of Cytomegalovirus Infections in Solid Organ Transplant Recipients

Despite advances in prevention and treatment, cytomegalovirus (CMV) infection and disease remain an expected problem in solid organ transplant recipients. Because of the effect of immunosuppressing medications, CMV primary, secondary, and reactivated infection requires antiviral medications to prevent serious direct and indirect effects of the virus. Side effects and drug resistance, however, often limit the capacity of traditional antiviral therapies. This article updates the clinician on current and promising approaches to the management and control of CMV in the solid organ transplant recipient.

Pediatric Intestinal Transplantation

Pediatric intestinal transplantation has moved from the theoretic to an actual therapy for children with irreversible intestinal failure who are suffering from complications of total parenteral nutrition. Owing to significant advancement in the management of intestinal failure and prevention of parenteral nutrition-related complications that have led to reduction in incidence of parenteral nutrition-associated liver disease and have improved intestinal adaptation, the indications for intestinal transplantation are evolving. Long-term outcomes have improved, but challenges in long-term graft function owing to chronic rejection and immunosuppressant-related complications remain the major opportunities for improvement.

Pediatric intestinal transplantation

The field of intestinal transplantation has experienced dramatic growth since the first reported cases 3 decades ago. Improvements in operative technique, donor assessment and immunosuppressive protocols have afforded children who suffer from life-threatening complications of intestinal failure a chance at long-term survival. As experience has grown, newer diseases, with more systemic manifestations have arisen as potential indications for transplant. After discussing the historical developments of intestinal transplant as a backdrop, this review focuses on the specific pre-operative indications for transplant as well as the great success that intestinal rehabilitation has witnessed over the past decade. A detailed discussion of evolution of immunosuppressive strategies is followed a general review of the common infectious complications experienced by children after intestinal transplant as well as the current long- and short-term results, including a section on new research on the quality of life in this challenging population of patients.

Cytomegalovirus Infection and Rates of Antiviral Resistance Following Intestinal and Multivisceral Transplantation

BACKGROUND

Cytomegalovirus (CMV) disease is a common and clinically significant complication following intestinal or multivisceral transplantation. CMV disease is more common in cases of serologic mismatch between donor and recipient. Though in some cases it may be asymptomatic, in the immunosuppressed population it often manifests with evidence of systemic infection or end-organ disease.

METHODS

We conducted a retrospective review of all patients undergoing intestinal or multivisceral transplantation over 8 years at our institution.

RESULTS

Forty-eight transplantations were performed, with 40% of the patients (19/48) having ≥1 episode of CMV viremia, which rose to 90% in the "donor-positive, recipient-negative" (DPRN) serologic mismatch group. The median time to 1st episode following transplantation was 22.3 weeks (range, 1-78) and median duration of each episode was 4.9 weeks (range, 1.6-37.4). Six of the 19 viremic patients (31.6%) developed virologic resistance with 4 of these occurring in the DPRN group. Four of the 6 patients with drug-resistant CMV died with CMV viremia. All patients with drug resistance acquired ganciclovir resistance; these patients were more challenging to manage with second-line toxicity-limited treatments, including foscarnet, cidofovir, and leflunomide. CMV immunoglobulin has been used and we briefly discuss the use of CMV-specific adoptive T-lymphocyte transfer in the management of 1 case.

CONCLUSIONS

Post-transplantation CMV disease continues to be challenging to manage, and there is little consensus on optimal management strategies in this patient group, with a significant requirement for novel therapies; these may be pharmacologic or cell based. Extensive multidisciplinary discussion is important for most cases, but particularly for those patients who acquire virologic resistance.

Cytomegalovirus Infection After Intestinal/Multivisceral Transplantation: A Single-Center Experience With 210 Cases. Transplantation. 2016;100:451-460. [PMID: 26247555 DOI: 10.1097/tp.0000000000000832]

BACKGROUND

Cytomegalovirus (CMV) infection is the most prevalent infectious complication after solid organ transplantation, and recipients of isolated intestinal transplantation (IIT)/multivisceral transplantation (MVT) are among those at the highest risk. Limited clinical data exist regarding CMV infection after IIT/MVT. The aim of this study is to analyze risk factors for posttransplant CMV infection and to assess the efficacy and validity of our prophylaxis and treatment regimens in intestinal transplantation.

METHODS

Medical records of 210 IIT/MVT patients were retrospectively reviewed. Posttransplant CMV prophylaxis regimen consisted of ganciclovir followed by 1 year of valganciclovir. The addition of CMV immunoglobulin (CMVIG) was decided according to donor/recipient CMV serostatus (D/R). All results of CMV PCR and/or pp65 antigenemia, and pathological reports were reviewed. Time to the incidence of CMV infection (viremia and/or tissue invasive disease) and risk factors for CMV infection were investigated.

RESULTS

CMV infection was observed in 34 of 210 (16%) with a median onset of 347 days. Rejection was significantly associated with CMV infection (P = 0.01, odds ratio = 2.61). In the high-risk serostatus group (D+/R-), prophylactic CMVIG and induction with high-dose rabbit antithymocyte globulin (>10 mg/kg) were associated with a lower CMV infection rate on univariate analysis. The CMVIG remained to be an independent factor on multivariate analysis (P = 0.04, hazard ratio = 0.93/dose). Mortality associated with CMV infection occurred in 4, and CMV infection adversely affected patient survival (P = 0.001, hazard ratio = 2.71).

CONCLUSIONS

Prophylaxis with CMVIG and appropriate induction with rabbit antithymocyte globulin may be important to reduce CMV infection in high-risk serostatus group (D+/R-).

Intestinal transplantation

Intestinal transplantation has now emerged as a lifesaving therapeutic option and standard of care for patients with irreversible intestinal failure. Improvement in survival over the years has justified expansion of the indications for intestinal transplantation beyond the original indications approved by Center for Medicare and Medicaid services. Management of patients with intestinal failure is complex and requires a multidisciplinary approach to accurately select candidates who would benefit from rehabilitation versus transplantation. Significant strides have been made in patient and graft survival with several advancements in the perioperative management through timely referral, improved patient selection, refinement in the surgical techniques and better understanding of the immunopathology of intestinal transplantation. The therapeutic efficacy of the procedure is well evident from continuous improvements in functional status, quality of life and cost-effectiveness of the procedure. This current review summarizes various aspects including current practices and evidence based recommendations of intestinal transplantation.

Infectious Complications Following Small Bowel Transplantation

Microbiological spectrum and outcome of infectious complications following small bowel transplantation (SBT) have not been thoroughly characterized. We performed a retrospective analysis of all patients undergoing SBT from 2004 to 2013 in Spain. Sixty-nine patients underwent a total of 87 SBT procedures (65 pediatric, 22 adult). The median follow-up was 867 days. Overall, 81 transplant patients (93.1%) developed 263 episodes of infection (incidence rate: 2.81 episodes per 1000 transplant-days), with no significant differences between adult and pediatric populations. Most infections were bacterial (47.5%). Despite universal prophylaxis, 22 transplant patients (25.3%) developed cytomegalovirus disease, mainly in the form of enteritis. Specifically, 54 episodes of opportunistic infection (OI) occurred in 35 transplant patients. Infection was the major cause of mortality (17 of 24 deaths). Multivariate analysis identified retransplantation (hazard ratio [HR]: 2.21; 95% confidence interval [CI]: 1.02-4.80; p = 0.046) and posttransplant renal replacement therapy (RRT; HR: 4.19; 95% CI: 1.40-12.60; p = 0.011) as risk factors for OI. RRT was also a risk factor for invasive fungal disease (IFD; HR: 24.90; 95% CI: 5.35-115.91; p < 0.001). In conclusion, infection is the most frequent complication and the leading cause of death following SBT. Posttransplant RRT and retransplantation identify those recipients at high risk for developing OI and IFD.

Risks and Epidemiology of Infections After Intestinal Transplantation

Intestinal transplantation has become a well-accepted and successful procedure to save the lives of patients suffering from intestinal failure and who have developed life-threatening complications of parenteral nutrition. Advances in all aspects of care, from the role of multidisciplinary intestinal rehabilitation services prior to transplant to the development strategies for early recognition of infectious sequelae and even the increasing availability of preventive strategies, have led to improved outcomes and a dramatic decline in infection-associated morbidity and mortality in children undergoing intestinal transplantation. Improvements in surgical techniques and immunosuppressive regimens have been essential components in these improvements, reducing risk of infection through reduction of technical complications and more optimal immunosuppression regimens. In addition, the development of molecular tools for early recognition of viral pathogens and an understanding of the timing and risks for infection have allowed for earlier and more successful treatments. Despite these improvements, infectious sequelae remain an important problem in this population, and additional efforts are needed to further minimize the risk of infectious sequelae in those children requiring this procedure.

Clinical utility of viral load in management of cytomegalovirus infection after solid organ transplantation

The negative impact of cytomegalovirus (CMV) infection on transplant outcomes warrants efforts toward improving its prevention, diagnosis, and treatment. During the last 2 decades, significant breakthroughs in diagnostic virology have facilitated remarkable improvements in CMV disease management. During this period, CMV nucleic acid amplification testing (NAT) evolved to become one of the most commonly performed tests in clinical virology laboratories. NAT provides a means for rapid and sensitive diagnosis of CMV infection in transplant recipients. Viral quantification also introduced several principles of CMV disease management. Specifically, viral load has been utilized (i) for prognostication of CMV disease, (ii) to guide preemptive therapy, (iii) to assess the efficacy of antiviral treatment, (iv) to guide the duration of treatment, and (v) to indicate the risk of clinical relapse or antiviral drug resistance. However, there remain important limitations that require further optimization, including the interassay variability in viral load reporting, which has limited the generation of standardized viral load thresholds for various clinical indications. The recent introduction of an international reference standard should advance the major goal of uniform viral load reporting and interpretation. However, it has also become apparent that other aspects of NAT should be standardized, including sample selection, nucleic acid extraction, amplification, detection, and calibration, among others. This review article synthesizes the vast amount of information on CMV NAT and provides a timely review of the clinical utility of viral load testing in the management of CMV in solid organ transplant recipients. Current limitations are highlighted, and avenues for further research are suggested to optimize the clinical application of NAT in the management of CMV after transplantation.

Small bowel transplantation complicated by cytomegalovirus tissue invasive disease without viremia. J Clin Virol. 2014;60:177-180. [PMID: 24703746 DOI: 10.1016/j.jcv.2014.03.005]

We report on a small bowel transplant patient, donor/recipient seropositive (D+/R+) for cytomegalovirus (CMV), with a clinical course complicated by CMV disease. Anti-CMV prophylaxis was given for 100 days. Immunosuppression consisted of alemtuzumab, tacrolimus, mycophenolate mofetil and prednisolone. Five months posttransplant, CMV tissue invasive disease of the upper gastrointestinal tract was evident without the presence of viremia, tested by quantitative polymerase chain reaction (PCR). Complete viral load suppression was achieved with intravenous ganciclovir, followed by valganciclovir for secondary prophylaxis. Mycophenolate mofetil and prednisolone were discontinued. Shortly thereafter the patient presented with recurrent CMV and candida esophagitis. While on ganciclovir and caspofungin, the patient developed CMV tissue invasive disease of the ileal graft, with persistent absence of viremia. Foscarnet and CMV immunoglobulin were added. Viral load declined to undetectable levels; however, clinical improvement did not occur due to occurrence of graft rejection. Despite infliximab and high dose prednisolone, graft rejection was progressive, requiring surgical explantation of the graft. This case highlights the importance of additional diagnostic tools such as endoscopy including PCR analysis of tissue samples. Extension of primary antiviral prophylaxis interval up to 6 months and prolonged retreatment for recurrent CMV disease may be useful to avoid severe CMV-related complications.

Gastrointestinal infections after transplantation

PURPOSE OF REVIEW

Recipients of both solid organ transplant and hematopoietic stem cell transplantation are at increased risk for infectious morbidity and mortality after transplantation due to on-going immunosuppression. Gastrointestinal infections have been increasingly reported in these populations.

RECENT FINDINGS

Increased reports of gastrointestinal infections including bacterial infection with Clostridium difficile, viral infection with norovirus and parasitic pathogens like cryptosporidium are emerging. Risk factors identified have focused on type of transplant, transplant immunosuppression regimens and exposures. Although many events are self-limiting, significant morbidity and rare mortality are reported.

SUMMARY

Improved diagnostic techniques have increased the reporting of several gastrointestinal infections after transplantation, affording improved understanding of the epidemiology of these diseases. Armed with this emerging data, prevention, recognition of infection and treatment strategies can be more thoroughly assessed in these at-risk populations.

Updated international consensus guidelines on the management of cytomegalovirus in solid-organ transplantation

Cytomegalovirus (CMV) continues to be one of the most common infections after solid-organ transplantation, resulting in significant morbidity, graft loss, and adverse outcomes. Management of CMV varies considerably among transplant centers but has been become more standardized by publication of consensus guidelines by the Infectious Diseases Section of The Transplantation Society. An international panel of experts was reconvened in October 2012 to revise and expand evidence and expert opinion-based consensus guidelines on CMV management, including diagnostics, immunology, prevention, treatment, drug resistance, and pediatric issues. The following report summarizes the recommendations.