Increased circulating levels of basement-membrane components in patients with abdominal aortic aneurysms--a pilot study.

Abstract

The decision for abdominal aortic aneurysm (AAA) repair is based on aneurysm size. However, smaller aneurysms can rupture, while larger ones can remain stable. New variables and markers are needed to better select patients at high rupture risk. The study was done to analyse if AAA patients have increased levels of circulating basement-membrane (BM) fragments. Circulating levels of BM components type IV and XVIII collagen were measured by enzyme-linked immunosorbent assay (ELISA) in 10 patients with AAA, nine patients with peripheral artery disease (PAD) and 10 healthy controls (CON). AAA patients had significantly increased levels of type IV and XVIII collagen compared with CON (134.0 ± 24.8 ng ml(-1) vs. 104.5 ± 16.4 ng ml(-1); p = 0.005 and 149.0 ± 56.9 ng ml(-1) vs. 59.6 ± 8.7 ng ml(-1); p < 0.001, respectively). The PAD patients did not have significantly increased levels of these fragments when compared with CON. In addition, the AAA patients had significantly increased level of type XVIII collagen (149.0 ± 56.9 ng ml(-1) vs. 58.3 ± 25.4 ng/ml(-1); p < 0.01) when compared with the PAD group. Based on this preliminary analysis of a small number of subjects, patients with AAA had significantly increased levels of circulating BM components. BM fragments should be studied further to establish their potential role as biomarkers for AAA.