Relation of Urinary Neutrophil Gelatinase-Associated Lipocalin (NGAL) with Renal Involvement in Pediatric Systemic Lupus Erythematosus Patients

Abstract

Background: Approximately 60%–80% of pediatric systemic lupus erythematosus (pSLE) patients have renal involvement during their disease course. Several potential urinary biomarkers have been identified to predict renal involvement. Among them, urinary neutrophil gelatinase-associated lipocalin (NGAL) has been associated with renal involvement, renal flare, and disease activity in pSLE patients. Objective: This study aims to assess the urinary NGAL levels and its association with renal involvement in pSLE patients. Materials and Methods: This cross-sectional study was conducted in the Paediatric Rheumatology Division, Department of Paediatrics, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh, from August 2019 to October 2020. In this study, 40 pSLE patients, including 18 renal pSLE and 22 non-renal pSLE patients, were included. In addition, 16 age- and sex-matched healthy children were recruited as controls. Detailed history, examination, and routine laboratory investigations, along with urinary NGAL, were conducted at the time of enrollment. Results: The mean age of the pSLE patients was 12.05 years, with 82.5% being female and a female-to-male ratio of 4.7:1. Among pSLE patients with renal involvement, all patients had proteinuria, followed by edema, hematuria, and hypertension. Urinary NGAL levels were significantly higher in pSLE patients with renal involvement compared to healthy controls and pSLE patients without renal involvement. A significant positive correlation was observed between 24 h urinary total protein (UTP) with urinary NGAL (r = 0.526, P = 0.02) in pSLE patients with renal involvement. Conclusion: Urinary NGAL levels were significantly higher in pSLE patients with renal involvement and positively correlated with 24 h UTP in pSLE patients with renal involvement.