The plasma level of mCRP is linked to cardiovascular disease in antineutrophil cytoplasmic antibody-associated vasculitis

Abstract

Background C-reactive protein (CRP) has two natural isomers: C-reactive protein pentamer (pCRP) and C-reactive protein monomer (mCRP). The levels of CRP are significantly elevated in patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). mCRP not only activates the endothelial cells, platelets, leukocytes, and complements, but also has a proinflammatory structural subtype that can localize and deposit in inflammatory tissues. Thus, it regulates a variety of clinical diseases, such as ischemia/reperfusion (I/R) injury, Alzheimer’s disease, age-related macular degeneration, and cardiovascular disease. We hypothesized that plasma mCRP levels are related to cardiovascular disease in AAV. Methods In this cross-sectional study, 37 patients with AAV were assessed. Brain natriuretic peptide (BNP) and mCRP in plasma were assessed by enzyme-linked immunosorbent assay (ELISA). The acute ST-segment elevation myocardial infarction (STEMI) was diagnosed by coronary angiography, and the Gensini score calculated. Echocardiography evaluated the ejection fraction (EF%), left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), and left ventricular mass index (LVMI). Estimated glomerular filtration rate (eGFR) was calculated based on serum creatinine, age, and gender. Results The plasma level of mCRP in AAV was significantly higher than that in healthy volunteers (P < 0.001). Then, mCRP and CRP levels were compared with and without STEMI complications in AAV. The plasma level of mCRP was higher, but that of CRP was lower in STEMI. The plasma level of mCRP was correlated with Birmingham vasculitis activity score (BVAS), eGFR, BNP, EF%, LVEDV, LVESV, LVMI, and STEMI complications’ Gensini score in AAV; however, CRP did not correlate with BNP, EF%, LVEDV, LVESV, LVMI, and Gensini score. Conclusions The plasma level of mCRP was related to cardiovascular diseases in AAV patients.

Associations of C-reactive protein isoforms with systemic lupus erythematosus phenotypes and disease activity

“…The ratio of mCRP/pCRP also differed, showing higher ratios in SLE compared to AAV. In contrast to Wu et al [ 30 ], mCRP in our study did not correlate with BVAS in AAV patients (rho = 0.17, p = 0.37). However, in general, the patients with AAV included herein overall had less severe disease, which could indicate that the levels of mCRP is greater at even higher degree of disease activity than the patients in this study had.…”

“…However, in general, the patients with AAV included herein overall had less severe disease, which could indicate that the levels of mCRP is greater at even higher degree of disease activity than the patients in this study had. Comparisons between this study and the study by Wu et al [ 30 ] shows that the level of mCRP in AAV differs greatly, where the patients herein had considerably lower levels. However, the mCRP levels in our study are more approximate to those reported by Chen et al [ 57 ], and in line with other autoimmune disorders and with patients of high CRP [ 58 – 60 ].…”

“…Given the recent publication by Wu et al [ 30 ] on mCRP and pCRP in AAV, we decided to include a group of well-characterized patients with AAV as disease controls. Not surprisingly, the pCRP and mCRP levels in SLE were lower than in AAV.…”

“…Although CVD continues to affect patients with SLE at young age, only few studies have been conducted to investigate the association of CVD and CRP specifically in SLE [ 8 ]. Recently, Wu et al showed that the levels of mCRP were higher in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) than in healthy controls, and that these levels were related to CVD in the patients [ 30 ].…”

Cardiovascular disease and ANCA-associated vasculitis: are we missing a beat?

“…More recently, Wu et al . [ 18 ] demonstrated that a C-reactive protein monomer (mCRP), which is responsible for activating platelets, complement and pro-inflammatory cytokines, was associated with CVD in AAV patients. This strengthens the link between AAV and CVD independent of conventional risk factors.…”