Background: Nephrotic syndrome is caused by a variety of glomerulopathy. The current study investigated the renal histopathological spectrum of patients with nephrotic syndrome who received a renal biopsy in our department within the last 15 years.
Methods: One thousand five hundred and twenty-three consecutive patients (≥14 years old at renal biopsy) with nephrotic syndrome were recruited. Patients were divided into four groups according to age at the time of renal biopsy. The renal histopathological spectrum was also compared between nephrotic-range proteinuria patients with and without hypoalbuminaemia.
Results: Among the 1523 patients, the most common cause of nephrotic syndrome was idiopathic membranous nephropathy (IMN) (20.7%), followed by minimal change disease (MCD) (20.4%). Among the patients aged 14-24, 25-44, 45-59 and ≥60 years, the most common cause of nephrotic syndrome was MCD (33.0%), lupus nephritis (LN) (23.0%), IMN (37.9%) and IMN (42.3%), respectively. Among the female patients aged 14-24 and 25-44 years, LN was the leading cause of nephrotic syndrome (35.8 and 36.2%, respectively). The proportion of patients with renal amyloidosis increased in parallel with patient age. The comparison between nephrotic patients with and without hypoalbuminaemia suggests that patients with MCD, LN or renal amyloidosis were more likely to develop hypoalbuminaemia.
Conclusions: The renal histopathological spectrum of nephrotic syndrome differs between ages. MCD, LN and IMN were the main cause of nephrotic syndrome among younger patients, and IMN was the main cause of nephrotic syndrome among older patients. The proportion of patients with renal amyloidosis increased in parallel with patient age.