Total Cholesterol Determination Accuracy in Dried Blood Spots.

Background Detecting total cholesterol in dried blood spots could aid in identifying individuals with a high likelihood of familial hypercholesterolemia and could be used as a screening measure. This study aims to assess the diagnostic accuracy of dried blood spots on Whatman 903 paper cards using a manual enzymatic technique. Methods: A total of 394 samples were collected as serum and dried blood spots were compared. Cholesterol was determined in serum using the automated reference method, while cholesterol on paper was measured using a manual enzymatic method. Within- and between-day diagnostic variability were analyzed. The correlation between both methods was assessed using Passing-Bablok regression and Bland-Altman plot. Internal validation of our correlation formula was performed on 149 samples, along with external validation of the formula proposed by Corso et al. Results: The within- and between-day coefficient of variation was found to be lower than 10.14% and 14.09%, respectively. Passing-Bablok regression indicated a precision of 0.803 and an accuracy of 0.96. Internal validation precision was measured at 0.716. The resulting positive and negative predicted values were 0.77 and 0.92, respectively, vs. 0.46 and 0.96 from the external formula. Conclusions: Total cholesterol analysis in dried blood spots demonstrates high precision and reproducibility. This method reliably enables the incorporation of this biological marker into neonatal screening for familial hypercholesterolemia detection.

Predictors of subclinical atherosclerosis in HIV.

BACKGROUND: Cardiovascular disease is a major cause of morbidity and mortality in people with HIV. The detection of subclinical atherosclerosis through vascular ultrasound allows us to identify patients at an increased risk of cardiovascular disease as a primary prevention strategy; this test is not routine. Our objective is to identify predictors of subclinical atherosclerosis in a population with HIV. METHODS: People with HIV infection were selected for primary prevention and underwent carotid and femoral ultrasound to detect atheromatous plaques. Logistic regression analysis including vascular risk factors was performed to predict the presence of atherosclerosis. RESULTS: One hundred eighty-three patients were included, 54% of whom were smokers; the mean duration of HIV infection was 9.52 years, and all patients were undergoing antiretroviral treatment. Subclinical atherosclerosis was present in 62.29% of the patients; 83.32% had plaque in the carotid territory, 57.93% in the femoral territory and 25.6% in both vascular territories. Compared to those without atherosclerosis, patients with atherosclerosis were on average 5.35 years older (53.86 vs. 48.51, p < 0.001) and had a higher prevalence of smoking (63.23% vs. 39.12%, p = 0.020) and a CD4/CD8 ratio below 0.7 (44.23% vs. 29.02%, p = 0.043). A CD4/CD8 ratio lower than 0.3 was always associated with subclinical atherosclerosis (95% confidence interval (CI): 83.9-100%). The inclusion of smoking, the CD4/CD8 ratio and age in the logistic regression analysis led to a diagnostic yield of 72% measured by the area under the receiving operator characteristic (ROC) curve (95% CI: 64-80%). CONCLUSIONS: Tobacco use, age and a CD4/CD8 ratio below 0.7 allow prediction of the presence of subclinical atherosclerosis in primary prevention. A CD4/CD8 ratio below 0.3 was a diagnostic indicator of atherosclerosis in HIV patients undergoing primary prevention in our sample.

Incorporation of biochemical parameters and diagnostic algorithms in the laboratory computer system for the early detection of lipid abnormalities from the lipid units. / Incorporación de parámetros bioquímicos y algoritmos diagnósticos en el sistema informático de laboratorio para la detección precoz de alteraciones lipídicas desde las unidades de lípidos.

INTRODUCTION: The combination of biochemical markers, together with the design and implementation of diagnostic algorithms in laboratory computer systems could become very powerful tools in the stratification of cardiovascular risk. OBJECTIVES: To implement new biochemical markers and diagnostic algorithms not yet available, in order to provide an estimation of cardiovascular risk and the diagnostic orientation of lipid alterations. MATERIAL AND METHODS: Study of the implementation of apolipoprotein B and lipoprotein (a), as well as the inclusion of different diagnostic algorithms. This was carried out jointly by the different Lipid Units of the Spanish Society of Atherosclerosis, Hospital Virgen Macarena in Seville, Hospital Juan Ramón Jiménez, Hospital Infanta Elena, and Hospital de Río Tinto during 2018 and 2019. RESULTS: The 4diagnostic algorithms entered into the Laboratory Information System, showed a total of 9,985 patients with c-LDL>200mg/dl. The diagnostic algorithm was extended to include Apo B, with 8,182 determinations showing an apolipoprotein B>100mg/dl). A total of 747 lipoprotein (a) were determined, of which 30.65% were> 50mg/dl. More than 2/3 (71.80%) showed results compatible with small and dense LDL particles. CONCLUSIONS: The implementation of new analytical parameters and algorithms in Primary Care laboratory results can identify a considerable number of patients with different alterations in lipid metabolism. This, together with the classic risk factors, could contribute to a correct risk stratification in preventing the progression of cardiovascular disease.