Assessment of Rapid Diagnostic Tests Algorithms in Transfusion Medicine Setting

Background: The rapid diagnostic tests play a pivotal role in the screening of viral markers in blood qualification for transfusion in limited resource setting. Therefore, it is important to assess their analytical performances to ensure their proper functioning. Material and Methods: We performed a cross- sectional study by successive recruitment to assess the diagnostic value of rapid diagnostic tests algorithms using ELISA as a reference test. A total of 661 blood from donors were enrolled for this study. Rapid Diagnostic Tests (RDTs) and ELISA tests were performed for each sample by a couple of double-blinded biotechnologists. Data were collected on case report form and captured in Microsoft Excel then the file was imported and analyzed using R software version 4.0.3. Results: The diagnostic accuracy for the algorithms are summarized in Table 1. For HIV-algorithm, the internal validity parameters were as follow: sensitivity (sens) 99.0% (95% CI = 97.8, 99.5);specificity (spec) 98.3% (95% CI = 90.9, 99.7);positive likelihood ratio (PLR) 57.4 (95% CI = 8.2, 401.0);negative likelihood ratio (NLR) 0.01 (95% CI = 0.0005, 0.02);diagnostic odd ratio (DOR) 4710. HBV-Ag/Ab RDTs achieve the following diagnostic accuracy: sens 99.7% (95% CI = 98.3, 99.9);spec 98.8% (95% CI = 96.9, 95.5);PLR 81.8 (95% CI = 30.9, 217.0);NLR 0.003 (95% CI = 0.0004, 0.02);DOR 14,110. The analytical performances of HCV-Ab RDTs were as follow: sens 98.7% (95% CI = 97.5, 99.4);spec 93.1% (95% CI = 78.0, 98.1);PLR 14.3 (95% CI = 3.8, 54.5);NLR 1.5 (95% CI = 0.8, 2.8);DOR 962.6. The parameters evaluating the external validity of RDTs screening for the three viral markers when the theorical prevalence was < 5% are summarized in Figure 3. At the prevalence < 5%, the NPV of the three RDTs were 99.96%, 99.99% and 99.94%. At the same prevalence, we found the following Positive Predictive Values (PPV) 70.82%, 77.59% and 37.35% for HIV-Ag/Ab RDTs, HBV-Ag RDTs and HCV-Ab RDTs algorithms, respectively. The overall areas under the received operating characteristic (ROC) curves were 98.6%, 99.2% and 99.2%;95.9% for HIV-Ag/Ab RDTs, HBV-Ag RDTs and HCV-Ab RDTs algorithms, respectively. Conclusion: RDTs algorithms can play a pivotal role in the screening of HIV-Ab/Ag, HBs-Ag in the setting of resources limited-countries where financial and technical expertise shortages are a standard fare. However, their use for diagnostic purposes must be done with great caution and the result must necessarily be confirmed with an ELISA or molecular technique particularly for HCV-RDTs algorithm which achieved an NLR value > 0.1.

Cardiovascular Risk Factors among Outpatients: An Alarming Sign of the Epidemiological Transition in Developing Country?

Background: Noncommunicable diseases are the leading cause of death in the world and low and middle-income countries suffer from preventable premature death. The aim of this study was to assess the risk factors for non- communicable disease (NCDs) in general and particular cardiovascular diseases (CVDs) among the outpatients of our department of medicine. Methods: We performed a cross-sectional study from April to December 2017 by the consecutive enrollment of outpatients who attended in our department of medicine of Hôpital Sominé DOLO de Mopti, Mali. Clinical and laboratory data were measured for cardiovascular risk assessment. Framingham Risk Score (FRS) and Systemic Coronary Risk Estimation (SCORES) were computed by using Framingham and SCORE equations. Metabolic syndrome was defined using the harmonized criteria from the International Diabetes Federation (IDF) and the American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI). Data were captured in excel and analyzed with R version 4.0.3. The statistical significance was set at p = 0.05. Results: A total of 292 patients were enrolled in this study. The prevalence of traditional cardiovascular risk factors was 36.64%, 21.57%, 14.04%, and 13.01% for high blood pressure, hyperglycemia, smoking, and alcohol consumption, respectively. The metabolic syndrome accounted for 23.63%. The mean body mass index was 26.10 ± 7 kg/m2. The overall 10-year risk for cardiovascular events or death was 26.3% and 8.6% according to the FRS and SCORE equation, respectively. The 10-year risk of cardiovascular events according to the FRS was significantly higher in subjects aged 50 and above compared to subjects aged under 50 years, 34.46% vs 13.16%, p < 0.001. Likewise, the 10-year risk for cardiovascular death according to SCORE equation was also significantly higher in subjects aged 50 and above compared to subjects under 50 years, 9.43% vs 2.09%, p = 0.02. Regarding gender, the FRS was significantly higher in men compared to women 49.50% vs 7.84%, p < 0.001. This same trend was observed with the SCORE, 14.67% vs 4.13%, p = 0.03. Conclusion: Our data corroborate the increasing prevalence of cardiovascular risk factors in SSA. A comprehensive cardiovascular risk factors assessment should be implemented in all stages of health facilities and a longitudinal follow-up could help shed a light on the epidemiology of NCDs in general and particularly CVDs and thereby improve their control policies in SSA.

Epidemiological Aspects of Diabetic Retinopathy at the Center of the Application of the Diploma of Specialised Studies in Ophthalmology (Cadeso)/Donka-Conakry

Purpose: The authors analyzed the epidemiological and clinical aspects of diabetic retinopathy at the Center for the Application of the Specialized Studies Diploma in Ophthalmology, Gamal Abdel Nasser University (CHU/ Donka) Conakry. Diabetic retinopathy (eye damage: eye and retina) is a serious complication of diabetes that affects 50% of type 2 diabetic patients. The eyes are particularly sensitive to damage to a small vessel. Diabetic retinopathy (DR) is the retinal localization of diabetic micro angiopathy resulting in impaired blood flow in the affected territories, the consequences of which will determine the clinical manifestations of the disease. DR is the leading cause of vision loss in adults of working age. Patients and Methods: This is a longitudinal prospective study carried out at CADES/O concerning 198 diabetic patients. The selection criteria were that the media be transparent and the fundus accessible over a period of six months from February to July 2018. Results: A total of 73 patients (37%) presented with diabetic retinopathy with an average age of 49.5 +/&#8722;9 years. The sex ratio (M/F) was 0.6 with a female predominance of 59%. Liberal profession patients were the most numerous 47.5%. Type 2 diabetes was the most common (85.86%). Diabetes fundus assessment was the most common reason for consultation (52%). Arterial hypertension was the most incriminated risk factor (45.45%) followed by the poor balance of diabetes (40.90%), and the age of diabetes (28.28%). 9.5% had diabetic retinopathy complicated by rubella iris, neovascular glaucoma and retinal detachment. Conclusion: Diabetic retinopathy is a common condition for which early detection and regular monitoring must be the rule to prevent, slow down or avoids irreversible blindness if possible, induced by this pathology by a good balance of diabetes and good control of associated risk factors.