The neutrophil-to-lymphocyte ratio (NLR) may predict morbidity and mortality in patients with community-acquired acute kidney injury (AKI), investigators reported at Kidney Week 2020 Reimagined, a virtual meeting sponsored by the American Society of Nephrology.
In a study of 308 patients with AKI (mean age 73 years; 58% male) attending a nephrology clinic in Spain, the mean NLR was 9.14. A total of 14.6%, 11.0%, and 74.4% of patients had Kidney Disease Improving Global Outcomes (KDIGO) AKI stage 1, 2, and 3, respectively. In addition, 68.8% had chronic kidney disease, and 17.2% required hemodialysis.
The source of AKI was prerenal in 69.5% of cases, renal in 23.1%, and obstructive in 7.5%. NLR according to this etiology was 8.55 prerenal, 9.37 renal, and 13.99 obstructive. Patients with prerenal AKI complicated by acute tubular necrosis had a significantly higher NLR compared with their counterparts: 10.7 vs 7.8 (P =.026).
NLR significantly correlated with peak creatinine (r=0.186; P =.001) and serum albumin (r= -0.237; P <.001), José M. Peña Porta, MD, and colleagues from the Lozano Blesa University Clinical Hospital in Zaragoza, Spain, reported. NLR also independently associated with longer hospital stay and higher mortality (along with the Liaño individual severity index). According to a multivariate binary logistic regression analysis, sex, age, Charlson comorbidity index, peak creatinine, serum albumin, chronic kidney disease, etiology of AKI, serum potassium, KDIGO AKI stage, need for hemodialysis, and the platelet-to-lymphocyte ratio did not independently predict outcomes after AKI.
Of the 308 patients in the cohort, 12.3% died. The best cut-off point for NLR to predict mortality was 6.68, with a sensitivity of 60% and specificity of 58%, the investigators reported.
“The NLR has been identified as a marker of inflammation and endothelial dysfunction,” Dr Peña Porta told Renal & Urology News. “Although more research is needed, NLR can serve as a predictive tool for the prognosis of community-acquired AKI.” The ease of obtaining NLR coupled with its low cost make it a potentially useful marker in assessing the hazards of AKI, he explained. The team is currently working on a follow-up study to gauge NLR’s utility.
Pena Porta JM, Castellano A, Coscojuela O, et al. Usefulness of the neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios in community-acquired AKI. Presented at: Kidney Week Reimagined; October 19-25, 2020. Poster PO0091.