This study shows a high frequency of HCV infection in patients on chronic hemodialysis in Kinshasa, with disparities between centers. Genotype 4 was the most common. The risk factors associated with HCV infection were the number of blood transfusions, the absence of EPO treatment, the time on HD as well as the characteristics of the centers.
Studies in Europe indicate a decrease in incidence of HCV infection in parallel with prevalence in hemodialysis centers (3) over the last 10 years, while others countries, especially in Eastern Europe, maintain a high incidence (10). The frequency of HCV infection we observed is higher than found in hemodialysis centers in Western Europe and North America (3, 4, 10). Reducing the number of blood transfusions in people on dialysis through administration of erythropoietin, aseptic measures including the use of single use disposables such as syringes and use of the right disinfectants, are other factors that have contributed to lowering the frequency of HCV infection in developed countries (5), as did the testing of blood donors for HCV from 1992 with increasingly sensitive tests (11). The recent treatments of HCV, particularly with DAA, may well increase the gap between countries because availability of DAA is not guaranteed in several countries including those in SSA (12). However, the average prevalence in this study are similar to those reported in other dialysis centers in SSA (7–9).
It is also known that in each country, the frequency of HCV infection in hemodialysis varies from center to center (3). This finding was confirmed in our study where we observed a disparity between the centers, with the frequency of HCV infection varying between 0 and 52.9%.
Despite the fact that the number of participants was low (only 17 patients out of 51) in the center practicing lower prices per HD session and the serological status at the initiation of HD was not well established, the high frequency of HCV infection in this center could be explained by the high treatment rates with an inadequate nursing medical staff-patients ratio probably responsible for nosocomial transmission. Because in a country like the DRC where dialysis is not subsidized and where social security and mutual funds are poorly developed, the consumables used in dialysis inevitably participate in the calculation of the prices of hemodialysis sessions (13). The motivation of nursing/medical staff and their number in relation to patients treated also have an impact on the quality of care. But these aspects were not analyzed in our study.
Only 2 patients seroconverted to HCV. This is nevertheless important knowing that, in accordance with the recommendations of the Congolese Society of Nephrology (SOCONEPH), the previous control went back to 6 months previously, unless the patient had to move to another dialysis center. In this case, serology checks for HCV, HIV and HBV are carried out systematically. The rate of seroconversion found (1.9%) is almost identical to that reported in the literature (14–16). The general measures that are recommended to prevent seroconversion are: limitation of handling and safe disposal of sharp or stinging objects and contaminated waste, hand washing, use of single-use surgical gloves, changed after each patient, training of personnel, the use of machines which allow thermal and chemical disinfection, disinfection of the external surfaces of the machine and HD environment (5).
Knowledge of the HCV genotype is important for the choice of antiviral treatment. As in studies conducted in the general population in SSA (17), and even in hemodialysis patients treated in Angola (18), genotype 4 was predominant in our study.
Several factors explain the HCV infection in hemodialysis, but the most frequently reported in the literature are blood transfusions and the duration of treatment in hemodialysis. Other factors were highlighted by the multicenter study (DOPPS) such as male gender, diabetes mellitus, black race, hepatitis B and alcohol (3). In our study, HCV infection was associated with the number of blood transfusions, the duration of hemodialysis, not taking EPO, and the type of hemodialysis center. Strengthening the national health system, improving the country's economic situation, can help increase the use of EPO in hemodialysis; which will reduce the number of transfusions. If a blood transfusion is necessary, a more demanding qualification of the blood must be ensured in the blood banks. The risk associated with the type of hemodialysis center shows that while improving access to treatment thanks to lower prices, the prevention and hygiene measures described above must be observed. Indeed a link with suboptimal hygienic precautions seems likely. Taking into account the very high frequency of HCV infection in this type of center, i.e. roughly one in 2 patients, we can wonder whether it is not advisable to dialyze these patients in isolated rooms from other uninfected patients? Admittedly this would equal to accept suboptimal hygienic precautions, and should be a last option resort. The hemodialysis setting has unique features that facilitate transmission of HCV, such as high risk of blood contamination of surfaces, objects and devices, and a large number of patients treated simultaneously in a shared space. In SSA countries, risk factors associated with HCV infection may be due to unsafe medical practices or other factors such as familial transmission, mother’s HCV status, or illiteracy. HCV prevention and control programs should include health education, increased community awareness towards the disease, controlling infection distribution in health-care centers, proper sterilization of medical and dental instruments, and ensuring safe supply of blood and blood-products (19).