RESUMEN
Objective Inflammatory markers such as C-reactive protein and procalcitonin have been shown to be independent markers of cardiovascular diseases. We aimed to assess the correlation between serum levels of procalcitonin, C-reactive protein and cardiovascular risk in type 2 diabetes. Methods We carried out a cross-sectional study at a tertiary level reference hospital in Yaounde, Cameroon. We assessed the cardiovascular risk using the Action in Diabetes and Vascular Disease: Preterax and Diamicron-MR Controlled Evaluation (ADVANCE) cardiovascular risk prediction model in 80 adults with type 2 diabetes. Serum procalcitonin and C-reactive protein were measured in 80 and 76 subjects respectively, using a highly sensitive quantitative enzyme-linked immunosorbent assay (ELISA) method. Correlations were examined using Spearman's rank correlation test and the correlation coefficients were compared using the Z-test statistic. Results Females represented the majority of the study population (62.5%). The median duration of diabetes was 5 (3-10) years and 62.5% of participants had a high cardiovascular risk score. Median serum procalcitonin levels was significantly higher in females compared to male participants: 2.48 (1.76-3.01 ng/mL) vs 1.42 (0.86-1.87 ng/mL); p<0.001. There was no difference in the serum C-reactive protein levels between females and males: 1.20 (0.33-3.33) mg/L vs 0.85 (0.36-2.77) mg/L; p=0.669. Procalcitonin was moderately correlated with cardiovascular risk (r=0.58, p<0.001). The correlation was slightly higher in females (R=0.56, p<0.001) versus males (R=0.49, p=0.005) although not significantly different (Z-statistic=0.734, p=0.463). Serum C-reactive protein did not show a meaningful correlation with cardiovascular risk (R=0.23, p=0.050). At a threshold of 2 ng/ml, serum procalcitonin identified participants with a high cardiovascular risk score, with a sensitivity and specificity of 64% and 80% respectively. Conclusion Compared to C-reactive protein, procalcitonin may be a better surrogate marker for cardiovascular risk prediction in this population with type 2 diabetes.
RESUMEN
BACKGROUND: In sub-Saharan Africa, intense perennial Plasmodium species transmission coincides with areas of high prevalence of the human immunodeficiency virus type 1 (HIV) infection. This implies that antiretroviral naïve HIV-infected people living within these regions are repeatedly exposed to Plasmodium species infection and consequently malaria. Natural killer (NK) cells are known to contribute to malaria immunity through the production of IFN-γ after exposure to Plasmodium falciparum-infected erythrocytes (infected red blood cells [iRBC]). However, in antiretroviral naïve HIV-1 infection, these functions could be impaired. In this study we assess the ability of NK cells from antiretroviral naïve HIV-1-infected people to respond to iRBC. METHOD: Magnetically sorted NK cells from antiretroviral naïve HIV-1-infected people were tested for their ability to respond to iRBC following in vitro coculture. NK cell IFN-γ production after coculture was measured through multiparametric flow cytometry analysis. RESULTS: Our data show a significant reduction (p = 0.03) in IFN-γ production by NK cells from antiretroviral naïve HIV-1-infected people after coculture with iRBCs. This was in contrast to the NK cell response from healthy controls, which demonstrated elevated IFN-γ production. NK cell IFN-γ production from untreated HIV-1-infected participants correlated inversely with the viral load (r = -0.5, p = 0.02) and positively with total helper CD4+ T-cell count (r = 0.4, p = 0.04). Thus, antiretroviral naïve HIV-1 infection can dampen NK cell-mediated immunity to P. falciparum infection in malaria-intense regions. This could in effect escalate morbidity and mortality in people chronically infected with HIV-1.