From Contrast Exposure to Renal Recovery: Incidence, Predictors, and Early Outcomes in A Resource-Limited Setting

Background: Contrast-induced nephropathy (CIN) is a major cause of acute kidney injury (AKI) worldwide, with variable prevalence across centres. New biomarkers, such as serum cystatin C, have been introduced for earlier AKI detection, but data from resource-limited settings remain scarce. This study assessed the incidence, predictors, and short-term renal outcomes of CIN using cystatin C and creatinine in patients undergoing contrast-enhanced procedures at the University of Maiduguri Teaching Hospital (UMTH), Nigeria. Methods: In this prospective study, 150 consenting adults (≥18 years) receiving contrast media were enrolled. Sociodemographic data and baseline laboratory measurements, including cystatin C, creatinine, and estimated glomerular filtration rate (eGFR), were obtained. CIN was defined as a ≥0.5 mg/dL or ≥25% rise in serum creatinine within 48–72 hours post-contrast. Logistic regression identified predictors of CIN, and renal outcomes were assessed over three months. Results: CIN prevalence was 30% using creatinine at 48 hours and 49.3% using cystatin C at 24 hours. Independent predictors included older age (OR = 1.346, p = 0.009), higher contrast volume (OR = 2.037, p = 0.001), elevated baseline creatinine (OR = 1.601, p = 0.006), and lower baseline eGFR (OR = 1.767, p = 0.003). Cystatin C sensitivity and specificity ranged from 51.1–68% and 52.4–58.1%, respectively, across 24–72 hours, without superiority over creatinine. Of CIN cases, 73.3% recovered within two weeks; 17.9% had persistent dysfunction, and 4.6% required dialysis. At three months, 62.5% of persistent cases recovered, 25% had ongoing impairment, and 12.5% remained on dialysis. Conclusion: CIN is common in UMTH, with significant short-term renal sequelae. Key risk factors include age, contrast volume, and pre-existing renal impairment. Cystatin C did not outperform creatinine in CIN detection in this cohort.