Nephrotic syndrome in infants and children: pathophysiology and management

Abstract

Nephrotic syndrome is defined by nephrotic-range proteinuria (≥40 mg/m²/hour or urine protein/creatinine ratio ≥200 mg/mL or 3+ protein on urine dipstick), hypoalbuminaemia (<25 g/L) and oedema. This review focuses on the classification, epidemiology, pathophysiology, management strategies and prognosis of idiopathic nephrotic syndrome of childhood, and includes a brief overview of the congenital forms.

Keywords: AKI: acute kidney injury; ANA: antinuclear antigen; ANCAs: anti-neutrophil cytoplasmic antibodies; ASOT: anti-streptolysin titres; CLC-1: cardiotrophin-like cytokine 1; CMV: cytomegalovirus; CNIs: calcineurin inhibitors; CNS: congenital nephrotic syndrome; DVT: deep vein thrombosis; ENaC: epithelial sodium channel; ESRD: end-stage renal disease; FRNS: frequently relapsing nephrotic syndrome; FSGS: focal segmental glomerulosclerosis; KDIGO: Kidney Disease Improving Global Outcomes; LCAT: lecithin-cholesteryl acyltransferase; MCD: minimal change disease; MMF: mycophenolate mofetil; NS: nephrotic syndrome; Nephrotic syndrome; RAAS: renin-angiotensin-aldosterone system; SRNS: steroid-resistant nephrotic syndrome; SSNS: steroid-sensitive nephrotic syndrome; VPF: vascular permeability factor; anti-dsDNA: anti-double stranded DNA; focal segmental glomerulosclerosis; idiopathic nephrotic syndrome; minimal change disease; oedema; steroid-resistant nephrotic syndrome; steroid-responsive nephrotic syndrome; suPAR: soluble urokinase-type plasminogen activator receptor; uPCR: urine protein:creatinine ratio.