Nephrotic syndrome in infants and children: pathophysiology and management

Abstract

Nephrotic syndrome is defined by nephrotic-range proteinuria (≥40 mg/m/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.

Nephrotic Syndrome in Children: Role of the Pediatrician, and the Nephrologist

“…La incidencia de SN reportada en menores de 16 años es 2-7 nuevos casos por 100 000 niños por año, y una prevalencia de 15 casos por 100 000 niños en el mundo con sustancial variabilidad según el origen étnico y geografía 2,6 . La edad de aparición más frecuente es 2-8 años, con la máxima incidencia entre los 3 -5 años⁷.…”

“…Esta clásicamente definida como una proteinuria en rango nefrótico (≥40 mg/m2/h o relación proteínas/creatinina ≥2 o proteinuria 3+ en la tira reactiva), hipoalbuminemia (<2.5 g/dL) y edemas 2,6,9 .…”

“…Entre el 80 a 90% de los niños mayores de un año con SN responden al tratamiento con corticoides dentro de las cuatro semanas (SN corticosensible). La mayoría de los niños con SN corticosensible presentan un episodio de recaída, y hasta el 50% presenta un SN recaedor frecuente o corticodependiente 1,2 . Las recaídas ocurren comúnmente durante periodos de actividad inmune incrementada, tales como infección del tracto respiratorio superior 3 .…”

Editorial

“…The articles in this special issue include many examples of such a pattern, ranging from post-infectious glomerulonephritis [4] and nephrotic syndrome [5,6] to neurogenic bladder [7] and acute kidney injury [8]. Experience gleaned from long-term cooperation between the paediatric nephrology units in Milan, Italy and Managua, Nicaragua [9] have confirmed that the complications associated with renal disease are more severe and the mortality rate higher in LMIC than in an HIC such as Italy.…”

“…On epidemiological grounds, data collection should be limited to the diseases which more frequently cause CKD. This special issue provides examples of such a clinical approach, particularly the idiopathic and secondary forms of steroid-resistant nephrotic syndrome [5,6], neurological bladder [7] and acute kidney injury [8]. Also, more common diseases, for example, urinary tract infections [13] and post-infectious glomerulonephritis [4], should be diagnosed and treated bearing in mind the possibility of renal damage secondary to congenital kidney and urinary tract malformations and the persistence of kidney disease marked by the presence of proteinuria and haematuria, respectively.…”