Abstract
Sickle cell nephropathy (SCN) develops via altered hemodynamics and acute kidney injury, but conventional screening tests remain normal until advanced stages. Early diagnostic biomarkers are needed so that preventive measures can be taken. This study evaluates the role of neutrophil gelatinase–associated lipocalin (NGAL) as a biomarker of SCN in steady state and vaso-occlusive crisis (VOC). In this case-control study, 74 sickle cell disease (SCD) patients (37 in steady state and 37 in VOC) and 53 control subjects had hematological and biochemical measurements including plasma and urine NGAL. Univariate and logistic regression analyses were used to find the associations between variables. The receiver operating characteristic (ROC) curve was used to determine the diagnostic performance characteristics of plasma and urine NGAL for detection of VOC. Plasma and urine NGAL, urine microalbumin:creatinine ratio, and urine protein:creatinine ratio were significantly higher in VOC. Microalbuminuria was present in 17.1% steady state and 32.0% VOC patients. Microalbuminuria showed significant correlations with age, plasma NGAL, WBC, and hemolytic parameters. Area under the ROC curve for plasma NGAL was 0.69 (95%CI = 0.567–0.813; p = 0.006) and 0.86 (95%CI = 0.756–0.954; p < 0.001) for urine NGAL. Urine NGAL cut-off value of 12.0 ng/mL had 95% sensitivity and 65% specificity. These results confirm the presence of nephropathy during VOC and suggest that plasma and urine NGAL would be useful in the identification of SCN. Urine NGAL should be used as the screening biomarker, and patients with VOC and urine NGAL > 12.0 ng/mL should be selected for aggressive management to prevent progression of renal damage.
Highlights
Sickle cell disease (SCD) is an inherited hemoglobinopathy that is relatively prevalent in Kuwait and the neighboring countries
Hb F fetal hemoglobin, eGFRcreat creatinine-based estimated glomerular filtration rate, eGFRcys cystatin C-based estimated glomerular filtration rate, NGAL neutrophil gelatinase–associated lipocalin a p value calculated by Mann-Whitney U test aspects to the nephropathy that accompanies diabetes mellitus [19]
As occurs in diabetic nephropathy (DN), progressive changes occur in the kidneys resulting in hyperfiltration, development of microalbuminuria and macroalbuminuria, and progressive reduction of GFR and end-stage renal disease (ESRD)
Summary
Sickle cell disease (SCD) is an inherited hemoglobinopathy that is relatively prevalent in Kuwait and the neighboring countries. Sickle cell nephropathy (SCN) is one of the recognized complications of SCD causing significant morbidity and mortality in patients with end-stage renal disease (ESRD). SCN is characterized by hyperfiltration at a young age, which results in hyposthenuria. At this age, patients with SCD have supra-normal glomerular filtration rate (GFR), proximal tubular dysfunction, and impaired ability to acidify urine or excrete potassium [6]. Glomerulonephropathy tends to occur as patients grow older, leading to microalbuminuria. This progresses to macroalbuminuria (gross proteinuria) and eventually ESRD.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
