Can sodium fluorescein cause contrast-induced nephropathy?

Abstract

Contrast-induced nephropathy (CIN) is a common cause of acute kidney injury (AKI), and can be diagnosed when the etiology of AKI is unclear other than via a contrast agent. Fluorescent angiography (FAG) with fluorescein sodium dye is generally considered to be safe for patients with kidney diseases. However, it remains unresolved whether or not FAG can induce CIN. Patients from two tertiary hospitals who underwent FAG and had serum creatinine results within 4 weeks before FAG and 3 days after FAG between 2001 and 2017 were retrieved. Cases with concurrent iodinated contrast imaging or undergoing dialysis were excluded from the analysis. CIN was defined by two criteria: CIN criteria as >0.5 mg/dL or >25% increase in serum creatinine (sCr) level within 3 days after FAG, and contrast-induced acute kidney injury (CIAKI) criteria as ≥0.3 mg/dL increase within 2 days or ≥50% increase within 7 days after FAG. A total of 979 patients were screened, and we found 124 patients with AKI after FAG. After excluding 32 patients with clear causes of AKI other than FAG, the incidence rates of CIN were 7.3% by CIN criteria and 6.4% by CIAKI criteria. CIN incidence had a U-shaped distribution according to chronic kidney disease (CKD) stages in CIN criteria, while linear association between CIN incidence and CKD stages were found in CIAKI criteria. Kaplan-Meier curves showed the CIN group was significantly associated with end-stage renal disease (ESRD) progression (log-rank P < 0.001, in both CIN criteria and CIAKI criteria), and adjusted hazard ratios by multivariable Cox regression were 2.23 [95% confidence interval (CI) 1.468-3.378] in CIN criteria and 2.17 (95% CI 1.462-3.232) in CIAKI criteria. According to CIN and CIAKI criteria, FAG may cause CIN and appeared to be a possible risk factor for ESRD progression. However, CIN or CIAKI criteria themselves may overestimate AKI and require meticulous attention to the interpretation of results.