Influence of acute kidney injury on the time to complete remission in adult minimal change nephrotic syndrome: a single-centre study

Aim: Acute kidney injury (AKI) is a common complication of minimal change nephrotic syndrome (MCNS), particularly in adults. We evaluated the prevalence of AKI at the onset of adult MCNS and analyzed the influence of AKI on the duration of achieving complete remission (CR). Methods: A retrospective, single-centre, dynamic cohort study was conducted with biopsy-proven, first-onset, adult MCNS patients treated with corticosteroids. Fifty-three consecutive patients diagnosed with MCNS from January 2000 to April 2014 were enrolled. Age, gender, daily urinary protein excretion, and serum creatinine levels were measured. To evaluate AKI during induction, we used the Kidney Disease: Improving Global Outcomes (KDIGO) Clinical Practice Guidelines for AKI and judged AKI stage according to the fluctuations in serum creatinine levels during the first 4 weeks of starting corticosteroid therapy. Results: Twenty patients (37.7%) met the AKI criteria and all 53 patients achieved CR within 1 year. Kaplan-Meier analysis showed that the median time to CR was significantly longer in patients with AKI than in patients without AKI. Cox proportional hazard analysis showed that the hazard ratio (HR) associated with the presence of AKI for achieving CR within 4 weeks was 0.36 after adjustment for age, gender, serum albumin, daily urinary protein excretion, hypertension, administration of 25% albumin, and methylprednisolone pulse therapy. A graded association was also observed between AKI stage and HR for achieving CR. Conclusions: The prevalence of AKI is high in adult patients with MCNS during induction therapy. AKI is an independent factor that delays the time to CR.