Infection-control precautions in hemodialysis

Infection-control precautions in hemodialysis constitute the principal operational strategy for preventing hepatitis C virus transmission within hemodialysis units. Their importance emerged as transfusion became a less significant source of infection and evidence increasingly pointed to nosocomial spread. The measures are deliberately universal: they apply to every patient and every dialysis station rather than depending on a separate physical pathway for those already known to be infected.

Background and Rationale

In the early 1990s, hemodialysis patients had high hepatitis C prevalence and incidence. Infection correlated with time on dialysis even after accounting for transfusion exposure, occurred more often in hemodialysis than in peritoneal or home dialysis, and was found in some patients who had never received a transfusion. Meanwhile, improvements in donor screening and the widespread use of erythropoiesis-stimulating agents sharply reduced transfusion-associated risk: the risk fell from about 0.5% per blood unit in the 1980s to approximately 0.0001%, or one case per million blood units, in the United States. Attention therefore shifted toward preventing transmission through the shared clinical environment.

The stakes extend beyond preventing a laboratory-defined infection. Hepatitis C is a systemic disease that can affect the liver and induce renal, autoimmune, and dermatological disease. Among patients receiving long-term dialysis, anti-hepatitis C positivity has been associated with increased all-cause mortality, while liver-related mortality is substantially higher and hepatocellular carcinoma and cirrhosis occur more frequently. Infection has also been associated with diminished mental quality of life, making prevention a measure that protects both survival and the experience of chronic treatment.

Core Measures at the Dialysis Station

The precautions begin with the hands of staff. Personnel should wash their hands with soap or antiseptic handwash and water before and after contact with a patient or with equipment at the dialysis station. Alcohol-based antiseptic gel is an acceptable alternative when the hands are not visibly contaminated. Disposable gloves should be worn when caring for a patient or touching potentially contaminated surfaces, and gloves must be removed whenever staff leave the station so that contamination is not carried into the next clinical space.

Every item that enters the dialysis process must be treated according to whether it can be discarded or disinfected. Single-use supplies are disposed of after treatment of one patient. Reusable objects are disinfected or assigned to a single patient. After each session, potentially contaminated station surfaces are cleaned with a low-level disinfectant when they are not visibly soiled; visibly contaminated surfaces require a stronger disinfecting agent. Even when dialyzer reuse cannot be avoided, reuse for a patient with hepatitis C can be undertaken only when strict infection-control procedures are implemented and consistently followed.

The protocol also includes waste management and the practical oversight of staff behavior. The guidelines recommend regular observational audits of infection-control procedures as part of performance reviews of hemodialysis units. Broad agreement about the correct precautions does not ensure that they are actually performed; the audit therefore turns infection control from a written consensus into an observable institutional responsibility.

Machines and Equipment

Machine safety depends on attention to small points where fluid can cross a protective boundary. The transducer protector should be replaced if its filter becomes wet. If fluid is visible beyond the filter, the machine should be removed from service after the session so that the internal filter can be changed and its housing disinfected. For a single-pass dialysis machine, disinfection of the internal pathway is not mandatory unless a blood leak has occurred, but sufficient time must be allowed between patients to disinfect the external surfaces of both the machine and its surrounding environment.

These instructions define infection control as a sequence rather than a single intervention. Hand contact, gloves, disposable supplies, reusable equipment, surface cleaning, waste disposal, filter inspection, and machine downtime form a linked chain. A failure at any one point can undermine precautions performed correctly at the others, which is why the guidelines emphasize both detailed procedures and continuing observation.

Isolation, Dedicated Machines, and Guideline Position

The KDIGO workgroup found no justification for routinely assigning dedicated dialysis machines to patients infected with hepatitis C and therefore did not recommend that practice; the recommendation carried moderate strength. Two large prospective observational studies, including the Dialysis Outcomes and Practice Patterns Study and an Italian study, found that isolating infected patients in a separate ward did not protect other patients from transmission after adjustment for potential confounders, including the prevalence of infection within the unit.

Isolation was consequently not recommended as a substitute for strict infection-control procedures for preventing transmission of bloodborne pathogens. The recommendation against isolation was weak rather than absolute, reflecting the absence of randomized controlled trials and the observational nature of the available evidence. Its practical meaning is nevertheless clear: separating patients or machines cannot compensate for failures in hand hygiene, glove removal, equipment disinfection, surface cleaning, or machine management.

Broader Prevention and Clinical Context

Infection-control precautions operate within a wider prevention system. In the general population, hepatitis C transmission is predominantly parenteral, and health-care-associated transmission in dialysis can be eradicated through strict adherence to hygiene rules. Screening remains essential because anti-hepatitis C antibodies identify exposure but do not distinguish resolved from active infection; active infection requires detectable hepatitis C virus RNA, with chronic infection established by the presence of both antibody and RNA. Accurate classification allows units to monitor risk while preserving the principle that precautions should not depend solely on prior identification of infected patients.

Prevention also protects future treatment and transplantation options. Chronic hepatitis C increases the risk of chronic kidney disease, and infection is clinically important in dialysis and transplant populations. Transplant candidates with active infection require evaluation for liver injury, while kidneys from hepatitis C-positive donors may be used safely in appropriately selected hepatitis C RNA-positive recipients under defined conditions. By limiting new infections in dialysis units, infection-control precautions help prevent additional liver disease, renal complications, mortality risk, and complexity in later transplant decisions.

The decisive lesson is institutional rather than technological. The decline in transfusion risk did not eliminate hepatitis C from hemodialysis; it revealed the importance of the treatment environment itself. Effective prevention rests on repeated, visible acts—clean hands, changed gloves, discarded single-use items, disinfected surfaces, inspected filters, protected machines, and audited practice. The strategy succeeds not through segregation, but through reliable conduct at every patient station and between every session.