Prevalence of Virological Markers HIV, HBV and HCV in Homozygous Sickle Cell Patients at Brazzaville University Hospital

In order to evaluate the seroprevalence of major viral markers, a descriptive study was carried out in homozygous sickle cell transfusion patients at the University Hospital of Brazzaville. The profiles were determined in 51 patients, 32 of whom were male and 19 female, with an age range of 17 to 51 years, admitted to the clinical hematology department of the University Hospital and to the National Reference Center for Sickle Cell Disease. The tests were performed on pre- and post-transfusion blood samples. The following reagents were used: GeenscreenTMultraHIVAg-Ab, MonolisaAg-HBs plus, Monoli-saHCV Ag-Ab Ultrade Bio-Radot for the detection of HIV, HBV and HCV by fourth generation ELISA tests (serological tests). The results showed that the indications for blood transfusion were: acute crises of anemia due to malaria and in some cases of Vaso-Occlusive Crises (VOC) resistance to analgesic treatment. The prevalence rates of the markers before the new transfusion were respectively: HIV: 0%, HBV: 1.96%, HCV: 3.92%. After transfusion, the final seroprevalence rates of the markers are: HIV: 0%, HBV: 5.88%, HCV: 3.92%. The seroconversion rate for HBV was 3.92%. One case of HBV + HCV co-infection (1.96%). Conclusion: Transfusion safety is achieved through good transfusion practices and the qualification of blood donations. Homozygous sickle cell disease, characterized by frequent anemia attacks, requires a guar-antee of efficient transfusion practices in order to limit microbial risks.


Introduction
Blood transfusion is a potentially life-saving intervention that plays an essential role in the management of patients in health care systems [1]. However, it remains fraught with many risks. Residual transfusion risk remains for several infectious agents [2] [3] [4]. Transfusion safety is the basis of blood transfusion and comprises several links, including good collection practices, donor selection, biological qualification of blood donations and distribution of labile blood products (LBS) [5]. Screening for infectious agents is a very important step in the process of biological qualification of blood donations in virology. It contributes to the prevention of transmission of viral diseases following blood transfusion or its derivatives in the population [6]. Among the virological markers, the presence of the major viruses, in particular HIV, HBV and HCV, is noted. The techniques for detecting these markers are very often limited to serological analyses, sometimes using rapid tests [7] [8] [9]. In Black Africa, the infectious safety of labile blood products is a key concern for blood transfusion centers because of the high prevalence of viral markers in the population [10] [11] [12] [13] [14].
Globally, there are significant variations in the screening tests performed, the strategies adopted for screening, and the overall quality and efficiency of the blood screening process [2]. In many countries, therefore, recipients of blood and blood products remain at an unacceptable risk of acquiring life-threatening infections. However, the residual risk of transmission of infectious agents has been significantly reduced. The feared silent window in infections (HIV, HBV and HCV) has been significantly reduced by the introduction of many reagents on the market [15] [16] [17].
The aim of our work is to evaluate the seroprevalence of major viral markers that pose a threat to transfusion safety in patients with sickle cell disease in the homozygous form.

Material
It consisted of blood samples taken from transfused sickle cell patients, in consultation in health care centers.

Method
This was a descriptive study conducted at the clinical hematology department of the Brazzaville Hospital and University Center (CHUB) and at the National Reference Center for Sickle Cell Disease (CNRD) between May and December 2017.
The inclusion criteria were: Patients with sickle cell disease in its homozygous form, a condition confirmed by a previous diagnosis (hemoglobin electrophoresis at alkaline pH).
Patients with a history of transfusion. Patients aged 17 years and older. Patients who agreed in writing, after reading the consent form (parent consent Open Journal of Blood Diseases for minor patients).
The criteria for non-inclusion were: Patients with no established diagnosis of sickle cell disease.
Patients with no history of transfusion.
Patients under 17 years of age; Patients (or parent of minor) not consenting to the study. Study variables were: sex, age, education level, sexual activity, serological status before and after the new transfusion, and number of erythrocyte units re-

Results and Discussion
Out of 96 patients who received a blood transfusion, 51 met the criteria, i.e. a frequency of 53.12%.

Distribution of Patients According to Age Range and Gender
The distribution of the poly perfused patients according to sex gave 19 male pa-Open Journal of Blood Diseases tients (37.26%) and 32 positive female patients (62.74%) with a sex ratio of 0.59.
The age of the patients ranged from 17 to 51 years with an average age of 24 years. According to the defined age ranges, 11 male (21.57%) and 13 female (25.49) patients were between 17 and 25 years of age; 7 male (13.72%) and 12 female (23.53%) patients were between 25 and 35 years of age; 1 male (1.96%) and 7 female (13.72%) patients were between 35 and 51 years of age. The results of this distribution are shown in Figure 1.

Distribution of Patients According to Education Level and Sexual Activity
The results of these variables showed that 3 patients (

Distribution of Patients According to Erythrocyte Unit Transfused
Out of 51 patients tested, 42 received two red blood cell units or concentrates corresponding to two blood bags, i.e. 82.35% of patients, and 9 patients received a single blood bag (17.65%).

Evolution of the Number of Transfusions Per Patient
Out of 51 patients, 20 (39.22%) were transfused 6 times or more. The other

Virological Profile of HIV, HBV, HCV Markers before and after the New Transfusion
The

Discussion
In our study the mean age was 24 years with extremes of 17 and 51 years. Polytransfused patients living with sickle cell disease in the homozygous form were Open Journal of Blood Diseases    Concerning the level of education, 5.88% of patients did not attend school, 52.94% had secondary education, only 15.69% of patients had reached higher education. NZINGOULA.S. [15] found that 40.25% of boys and 46.7% of girls were behind in school and 13% of children were not in school in a study on sickle cell disease [20] [21] [22].
Serological monitoring of markers showed that in the case of HIV, no patient carried the HIV marker before and after transfusion, i.e. 100% seronegative patients. These results are similar to those obtained in Marseille by BLOUIN et al. [23] who showed that there were no post-transfusion incidents related to HIV.
These results can be explained by the reinforcement of transfusion safety measures. However, the work carried out by LAPERCHE [24] in France observed two (2) cases of HIV-related contamination. These differences may be due to the methodology adopted and the duration of the study.
In the case of HBV: The pre-transfusion results show that, out of a total of 51 patients, 50 patients (98.04%) were HBV negative and 1 patient was HBV positive (1.96%).
These HBV positive patients are found in the age range of 22 -45 years with declared sexual activity. In our study, several patients admitted to having unprotected sex. The hepatitis B marker values obtained are similar to those of NGOSACK et al. [25] in Cameroon, who worked on 108 polytransfused patients of whom 7 were HBV positive (6.48%). Their results also showed that the positive patients were between 21 and 30 years of age and that contamination was largely through sexual contact.
Concerning the Hepatitis C virus, the results of the 1st and 2nd tests were the same: 49 seronegative patients (96.08%) and 2 seropositive patients (3.92%).
NGOSACK et al. [25] showed that the prevalence of. HCV antibody in polytransfused patients increased with the number of transfusions received and with  [26] carried out on 74 HCV seropositive patients showed that 59 of them were female (20%) with an average age of 31 ± 7.6 years with extremes ranging from 18 to 52 years. They showed that the most common risk factor for HCV contamination was tattooing or scarification (44.6%) followed by blood transfusion (36.6%).
The results of our study showed only one case of HBV + HCV co-infection.
This was a 45 year old patient, seropositive to both HBV and HCV, and therefore a HBV + HCV case with a prevalence of 1.96%. This result is higher than that obtained by ELIRA et al. and Attia et al. [13] [27], who found HBs + HCV co-infections of 0.14%.

Conclusions
The virological profile of polytransfused patients living with sickle cell disease in the homozygous form at the University Hospital of Brazzaville can be considered satisfactory for HIV with no positive cases, but unsatisfactory for HCV with 2 positive cases and HBV with 3 positive cases for the population of the present study. The observed seroconversion reminds us that blood transfusion is not always risk-free. Thus, for maximum transfusion safety, a rigorous selection of blood donors and a biological qualification of blood products are necessary. To stop the rapid spread of these infections, more precise screening must be carried out using molecular biology tests.
Access to care and non-compliance with preventive methods are challenging to be met. Thus, transfusion safety is achieved through good transfusion practices and the qualification of blood donations.

Proposed Algorithms
In view of the seriousness of infections due to major viruses and the existence of co-infections between these viruses, we encourage the health authorities to apply effective means of prevention such as rigorous selection of blood donors.
The suggestion to the public authorities is to systematize the vaccination against hepatitis B and the systematic screening by efficient tests of hepatitis C.

Conflicts of Interest
The authors declare no conflicts of interest.