Assignment of cytomegalovirus infection status in infants awaiting solid organ transplant: Viral detection methods as adjuncts to serology

Healthcare disparity and its associations with cytomegalovirus disease in pediatric liver transplant recipients in South Africa

BACKGROUND

Cytomegalovirus (CMV) infection and disease are preventable complications following pediatric liver transplantation (PLT), despite the use of prophylaxis to minimize the risk of CMV disease. We evaluated the incidence and complications of CMV disease in PLT recipients in South Africa (SA), with particular reference to potential differences in outcome between state and private sector patients.

METHODS

Medical records of patients younger than 16 years of age who received liver transplants between January 1, 2012, and August 31, 2018 were analyzed.

RESULTS

Records of all 150 PLT patients were retrieved. The median age at transplant was 29.2 months (95% confidence interval 15.6-58.4) and follow-up was 46.3 months (interquartile range 27.6-63.1). Sixty-six (44%) patients were high risk, 79 (52.7%) were intermediate risk, and five (3.3%) were low risk for CMV infection. Forty-three (28.9%) patients had CMV DNAemia following transplantation, and 30 (20.1%) developed CMV disease. Receipt of care in the private sector was consistently associated with a lower hazard of CMV disease (adjusted hazard ratio [aHR] ranging from 0.36 to 0.43) and a consistently lower hazard of death among recipients at high risk for CMV disease and/or those who developed CMV disease (aHR ranging from 0.28 to 0.33).

CONCLUSION

Receipt of care in the private health sector was associated with a consistently lower hazard of CMV disease and death in individuals with CMV disease and/or at high risk for CMV disease. Policies aimed at creating a more equitable healthcare system in SA may mitigate the differential burden of illness associated with CMV in PLT recipients.

Reduced-intensity single-unit unrelated cord blood transplant with optional immune boost for nonmalignant disorders

Children with many inherited nonmalignant disorders can be cured or their condition alleviated by hematopoietic stem cell transplantation (HSCT). Umbilical cord blood (UCB) units are a rapidly available stem cell source and offer great flexibility in HLA matching, allowing nearly uniform access to HSCT. Although reduced-intensity conditioning (RIC) regimens promise decreased treatment-related morbidity and mortality, graft failure and infections have limited their use in chemotherapy-naive patients. We prospectively evaluated a novel RIC regimen of alemtuzumab, hydroxyurea, fludarabine, melphalan, and thiotepa with a single-unit UCB graft in 44 consecutive patients with inborn errors of metabolism, immunity, or hematopoiesis. In addition, 5% of the UCB graft was re-cryopreserved and reserved for cord donor leukocyte infusion (cDLI) posttransplant. All patients engrafted at a median of 15 days posttransplant, and chimerism was >90% donor in the majority of patients at 1-year posttransplant with only 1 secondary graft failure. The incidence of grade II to IV graft-versus-host disease (GVHD) was 27% (95% confidence interval [CI], 17-43) with no extensive chronic GVHD. Overall survival was 95% (95% CI, 83-99) and 85% (95% CI, 64-93) at 1 and 5 years posttransplant, respectively. No significant end-organ toxicities were observed. The use of cDLI did not affect GVHD and showed signals of efficacy for infection control or donor chimerism. This RIC transplant regimen using single-unit UCB graft resulted in outstanding survival and remarkably low rates of graft failure. Implementation of the protocol not requiring pharmacokinetic monitoring would be feasible and applicable worldwide for children with inherited disorders of metabolism, immunity, or hematopoiesis. This trial was registered at www.clinicaltrials.gov as #NCT01962415.

Cytomegalovirus in solid organ transplant recipients-Guidelines of the American Society of Transplantation Infectious Diseases Community of Practice

Cytomegalovirus (CMV) is one of the most common opportunistic infections that affect the outcome of solid organ transplantation. This updated guideline from the American Society of Transplantation Infectious Diseases Community of Practice provides evidence-based and expert recommendations for screening, diagnosis, prevention, and treatment of CMV in solid organ transplant recipients. CMV serology to detect immunoglobulin G remains as the standard method for pretransplant screening of donors and transplant candidates. Antiviral prophylaxis and preemptive therapy are the mainstays of CMV prevention. The lack of a widely applicable viral load threshold for diagnosis and preemptive therapy is highlighted, as a result of variability of CMV nucleic acid testing, even in the contemporary era when calibrators are standardized. Valganciclovir and intravenous ganciclovir remain as drugs of choice for CMV management. Strategies for managing drug-resistant CMV infection are presented. There is an increasing use of CMV-specific cell-mediated immune assays to stratify the risk of CMV infection after solid organ transplantation, but their role in optimizing CMV prevention and treatment efforts has yet to be demonstrated. Specific issues related to pediatric transplant recipients are discussed.