The United States functions in the evidence as both a clinical setting and a policy environment in which HCV infection is managed across dialysis, the kidney-transplant waiting list, and transplantation itself. Its significance lies in the tension between measurable excess risks—higher mortality, diabetes, liver disease, and graft complications—and the fact that kidney transplantation still offers HCV-infected patients a survival advantage over remaining on dialysis or waiting indefinitely.

The United States as a Transplant Setting

In the United States, the shortage of donated organs places patients inside a long and consequential waiting process. By May 2011, almost 111,000 people were registered on the national transplant waiting list, while only about 28,000 transplant procedures were performed each year. The disparity means that many patients deteriorate or die before receiving an organ, and it makes the classification of HCV-infected candidates more than a diagnostic exercise: screening, staging, and continued eligibility determine whether a patient remains a candidate for kidney-alone transplantation or must be redirected toward combined liver-kidney transplantation.

Waiting times at some United States centers approached five to seven years. That interval required an active surveillance protocol rather than a single prelisting assessment. Candidates who had not previously been tested were to undergo anti-HCV antibody screening by enzyme immunoassay, with confirmation by nucleic acid testing in low-prevalence regions, or direct nucleic acid testing in high-prevalence settings. Patients with positive nucleic acid testing were to be placed on hold and referred to a hepatologist for evaluation and possible treatment. Those who had achieved a sustained virological response were to undergo at least annual nucleic acid testing, while candidates who remained viremic required annual assessment for progression of liver disease.

Mortality and the Waiting List

United States data link HCV infection with a heightened burden of mortality among patients receiving dialysis and among those awaiting transplantation. A meta-analysis of seven observational studies involving 11,589 dialysis patients found an independent association between anti-HCV positivity and death, with a summary relative risk of 1.34. Liver-related mortality was especially elevated: the unadjusted relative risk was 5.89 for anti-HCV-positive patients compared with anti-HCV-negative patients, and hepatocellular carcinoma and cirrhosis were more frequent causes of death in the positive group.

The United States evidence also makes the causes of death on the waiting list more complicated than liver disease alone. In a single-center study of HCV-infected kidney candidates, diabetes was more prevalent among infected patients and was the only usual clinical variable associated with death in a Cox regression model. Diabetes carried a hazard ratio of 2.17, whereas liver disease was not predictive of mortality in that model. Consequently, surveillance of listed HCV-infected patients had to include cardiovascular risk, particularly because chronic kidney disease already carries a heavy cardiovascular burden and diabetes was common in this cohort. Death, rather than liver disease, was the primary reason HCV-infected patients were removed from the list in the reported study.

United States registry and study data nevertheless support transplantation as the preferred form of renal replacement therapy for an HCV-infected patient without advanced liver injury. Patients who received a kidney transplant had lower mortality than comparable anti-HCV-positive patients who remained on dialysis or on the waiting list. In one analysis, transplantation was associated with a relative risk of death of 0.31 during the seven- to forty-eight-month posttransplant period. Another time-dependent analysis of 175 listed HCV-infected candidates found an initially increased hazard during the first six months after transplantation, followed by a marked reduction from months seven through eighty-four, when the hazard ratio fell to 0.32. The early danger did not erase the later survival advantage.

Registries, Outcomes, and Clinical Uncertainty

The United States experience also shows how registry evidence can complicate apparently straightforward clinical conclusions. HCV-infected kidney recipients generally had inferior long-term survival compared with recipients without evidence of infection, particularly in studies extending beyond ten years after transplantation. A meta-analysis of eight clinical trials involving 6,365 patients estimated a mortality relative risk of 1.79 associated with HCV infection, with part of the excess explained by liver-related death. Yet many of the underlying studies classified infection through enzyme-linked immunosorbent assays rather than nucleic acid testing and lacked pretransplant liver biopsies, leaving the contribution of preexisting liver damage uncertain.

Graft survival was also worse in much of the United States-linked evidence. In one comparison, 488 anti-HCV-positive recipients had an adjusted relative risk of graft loss of 1.53 compared with 2,877 seronegative recipients. Registry findings from Australia and New Zealand, cited alongside United States practice, reported a five-year adjusted hazard ratio of 1.71 for graft failure in the anti-HCV-positive cohort. Glomerulonephritis and chronic allograft nephropathy were more common causes of graft loss. These findings created a double register of transplantation: it could extend the patient’s life while exposing the graft to complications associated with persistent HCV infection, immunosuppression, and preexisting renal and hepatic disease.

HCV-Positive Donor Kidneys

Organ shortage in the United States encouraged debate over whether kidneys from HCV-positive donors should be discarded. The United States Renal Data System reported reduced survival among recipients of kidneys from HCV-positive donors compared with recipients of kidneys from HCV-negative donors, regardless of the recipient’s HCV serologic status; the difference became apparent about two years after transplantation. A higher incidence of posttransplant diabetes mellitus was proposed as a possible intermediate complication, prompting calls for caution and for complete disclosure to potential recipients.

The same American registry evidence also revealed a potential benefit. HCV-positive recipients who received kidneys from HCV-positive donors waited 310 fewer days than the average waiting time at their center and 395 fewer days than comparable recipients who waited for HCV-negative kidneys. Receiving an HCV-positive kidney was independently associated with better survival than remaining on the waiting list, with an adjusted hazard ratio of 0.76. The apparent contradiction—later risk in some recipient comparisons but shorter waiting and better survival than continued waiting—illustrates why donor and recipient selection, baseline health, HCV RNA status, and time without a transplant must be considered together.

The policy question was intensified by organ wastage. HCV-positive kidneys were reported to be 2.60 times more likely to be discarded than HCV-negative kidneys. For HCV RNA-positive patients who could not undergo, refused, failed, or withdrew interferon treatment, transplantation with an HCV-positive kidney was presented as a possible route to a more favorable course than continued dialysis, with the practical advantage of reducing time on the waiting list. The United States therefore appears not simply as a place where organs are allocated, but as a setting in which infection status can transform an otherwise usable kidney into either a rejected risk or a time-saving opportunity.

Institutional Governance and Infection Control

The United States also provides the setting for national observations about dialysis-unit infection control. Large prospective observational evidence, including the Dialysis Outcomes and Practice Patterns Study, found that isolating HCV-infected patients did not protect other dialysis patients from transmission after adjustment for confounding factors, including the prevalence of HCV within the unit. This supported the conclusion that isolation should not substitute for strict infection-control procedures.

The broader evidence reviewed by the KDIGO workgroup likewise found no convincing reason to dedicate dialysis machines exclusively to HCV-infected patients. Across twenty molecular-virology investigations of newly diagnosed cases linked to already infected source patients, failures in infection-control procedures were considered the probable cause in every study, while the internal machine circuit was implicated as a possible route in only one. In eighteen of the twenty studies, some or all newly infected patients had not shared a dialysis machine with the presumed source patient. The resulting United States-relevant policy logic was therefore organizational rather than spatial: reliable precautions, surveillance, testing, and informed allocation were more important than simply separating people or assigning special machines.