Impact of mannose-binding lectin deficiency on radiocontrast-induced renal dysfunction: a post-hoc analysis of a multicenter randomized controlled trial

BACKGROUND: Local renal ischemia is regarded as an important factor in the development of contrast-induced nephropathy (CIN). Mannose-binding lectin (MBL) is involved in the tissue damage during experimental ischemia/reperfusion injury of the kidneys. The aim of the present study was to investigate the association of MBL deficiency with radiocontrast-induced renal dysfunction in a large prospective cohort. METHODS: 246 patients with advanced non–dialysis-dependent renal dysfunction who underwent radiographic contrast procedures were included in the study. Baseline serum MBL levels were analyzed according to the occurrence of a creatinine-based (increase of ≥0.5 mg/dL or ≥25% within 48 hours) or cystatin C-based (increase of ≥10% within 24 hours) CIN. RESULTS: The incidence of creatinine-based and cystatin C-based CIN was 6.5% and 24%, respectively. MBL levels were not associated with the occurrence of creatinine-based CIN. However, patients that experienced a cystatin C increase of ≥10% showed significantly higher MBL levels than patients with a rise of <10% (median 2885 (IQR 1193–4471) vs. 1997 (IQR 439–3504)ng/mL, p = 0.01). In logistic regression analysis MBL deficiency (MBL levels≤500 ng/ml) was identified as an inverse predictor of a cystatin C increase ≥10% (OR 0.34, 95% CI 0.15-0.8, p = 0.01). CONCLUSION: MBL deficiency was associated with a reduced radiocontrast-induced renal dysfunction as reflected by the course of cystatin C. Our findings support a possible role of MBL in the pathogenesis of CIN.