Adult Cord Blood Transplantation (CBT) Recipients Have a High Incidence of Early Acute Kidney Injury (AKI) and AKI Increases Long-Term Chronic Kidney Disease (CKD) Risk

Abstract

Introduction While adult double unit CBT (dCBT) has disease-free survival comparable to that of HLA-matched adult donor allografts, frequent patient (pt) comorbidities combined with chemotherapy/TBI & cyclosporine-A (CSA) contribute to AKI risk. Using KDIGO criteria, we analyzed renal injury incidence & risk factors in adults undergoing dCBT. Methods Adult dCBT pts transplanted 2006-2016 for hematologic malignancies using Cy/ Flu/ Thio/ TBI 400 cGy & CSA (therapeutic range 250-450)/ MMF were analyzed. Using day 0 - 100 creatinines, maximum grade (gr.) AKI [gr. 1 (1.5 - 3-fold baseline)] was calculated. If pts had multiple episodes, the highest grade was analyzed. The 2-yr CKD incidence (> 90 days of GFR Results 153 pts [median 51 years (range 23-65), 114/153 (75%) acute leukemia, 27/153 (18%) African, 88/153 (58%) CMV seropositive] were transplanted. No patient had chronic kidney disease pre-dCBT; 32/153 (21%) had hypertension & 12/153 (8%) were diabetic. Median aaHCT-CI was 3 (range 0-9) with 92/153 (60%) pts having a score > 3. 34 (22%) pts had High-Very High rDRI diagnoses. Median pre-dCBT albumin was 4 (range 2.6 - 5.2). 96% of pts engrafted, 76% had grade II-IV acute GVHD by day 100 & 90% were alive & disease-free at day 100 (11 TRM, 3 relapse). 127 pts had AKI (45 gr. 1, 60 gr. 2, & 22 gr. 3) for a day 100 grade 1-3 AKI cumulative incidence of 83% (95%CI: 77-89) (median onset 40 days, range 0-96) & 54% (95%CI: 46-62) for gr. 2-3 AKI (median onset 43 days, range 0-96) (Figure 1). The mean of the 3-day mean CSA level preceding AKI onset was high at 360 ng/ml. African ancestry, CMV seropositivity & low day -7 albumin level & post-dCBT variables of ICU admission, nephrotoxic drug exposure & bacteremia were associated with gr. 1-3 AKI (Table 1A). In multivariate analysis, low day -7 albumin, ICU admission & nephrotoxic drugs were significant (Table 1B). With a median 40 months (range 12-125) survivor follow-up, 34/109 (31%) evaluable pts had CKD at 2-yrs with 1 pt requiring long-term dialysis. Grade 2-3 AKI prior to day 100 was associated with a higher likelihood of having CKD at 2-yrs: 38% vs 25% (Figure 2). Conclusion dCBT recipients are at significant risk for AKI which increases the likelihood of long-term CKD. Early recognition of impending AKI & prompt intervention is critical to mitigate severe kidney injury & long-term impairment. Prevention strategies include adequate hydration, tight CSA level control & substitution of non-nephrotoxic medications (e.g. Letermovir CMV prophylaxis instead of pre-emptive foscarnet, non-aminoglycosides antibiotics, azoles rather than amphotericin, PO cidofovir instead of IV). Investigation of novel GVHD prophylaxis that could permit lower CSA dosing & early AKI detection using biomarkers should also be investigated.