Evaluation of acute infection-induced endothelial dysfunction and its potential mediators.

Objectives: Inflammation plays an important role in the pathophysiology of atherosclerosis. Some studies suggest a link between chronic infections, an inflammatory state, and endothelial dysfunction. However, data related to acute infections are scant. We have investigated: (i) the effect of acute infection on endothelial function; (ii) the role of potential mediators of endothelial dysfunction.

Methods: Forty patients 40 years old with acute infection (mean age 53.9 +/- 8.8 years), without coronary artery disease or its equivalents were enrolled. Endothelial function and blood levels of high sensitive C-reactive protein, interleukin-6, tumour necrosis factor-a, high-density lipoprotein cholesterol (HDL), low-density lipoprotein cholesterol (LDL), apolipoprotein-A1 (Apo-A1) and apolipoprotein-B100 (Apo-B100) were assessed in the acute infection phase and 1 month after recovery. Endothelial function was evaluated by brachial artery flow-mediated vasodilation (FMD).

Results: The intraclass correlation coefficients for intra- and interobserver agreement for FMD measurements were 0.98 (95% CI: 0.95-0.99) and 0.93 (95% CI: 0.83-0.97), respectively. FMD improved significantly 1 month after recovery (P < 0.001). Compared to the levels at 1 month, inflammatory markers, LDL cholesterol, LDL/HDL ratio, Apo-B100 and Apo-B100/Apo-A1 ratio were significantly higher. However, HDL and apo-A1 were significantly lower in the phase of acute infection. Change in FMD from baseline to 1 month after recovery correlated significantly only with the change in Apo-A1 (r = 0.35, P = 0.027).

Conclusions: Acute infection causes transient endothelial dysfunction. It increases inflammatory markers and generates an atherogenic lipid profile. Among the parameters evaluated, only the change in Apo-A1 level was associated with acute infection-induced endothelial dysfunction.