What is the typical age range for nephrotic syndrome and nephritic syndrome?

Age Distribution of Nephrotic and Nephritic Syndromes

Nephrotic Syndrome

Nephrotic syndrome in children typically presents between ages 2-7 years, with peak incidence in the preschool years, while congenital forms manifest before 3 months of age. 1, 2

Age-Specific Patterns

• Congenital nephrotic syndrome: Presents within the first 3 months of life, often requiring specialized management at tertiary pediatric nephrology centers 1

• Idiopathic nephrotic syndrome (most common):

  • Peak onset between 2-7 years of age 2
  • Can occur during the first year of life but this is uncommon 2
  • Annual incidence of 1-4 per 100,000 children under age 16, with variation by race and geography 2, 3
  • Most commonly affects children aged 2-10 years 4

• Pediatric age range: The condition predominantly affects children under 12 years, with the KDIGO 2021 guidelines distinguishing management approaches for those <12 years versus ≥12 years 1

Histologic Correlation by Age

• Children under 12 years: Approximately 85-90% have minimal change disease (MCD) and respond to steroids without requiring initial kidney biopsy 1, 2

• Adolescents ≥12 years: Require kidney biopsy at presentation due to higher likelihood of alternative diagnoses including focal segmental glomerulosclerosis (FSGS) and membranous nephropathy 1

• FSGS prevalence: Accounts for 7-20% of nephrotic syndrome cases in children, with significantly higher percentages in adults 1

Critical Age-Related Decision Points

Biopsy is indicated in children <1 year of age or >10 years of age presenting with nephrotic syndrome, as these age groups have higher likelihood of non-minimal change disease 1, 2

Additional biopsy indications regardless of age include: macroscopic hematuria, hypertension, low C3 levels, persistent renal failure, or steroid resistance 2

Nephritic Syndrome

The provided evidence does not contain specific age distribution data for nephritic syndrome as a distinct entity. However, the guidelines emphasize that nephritic presentations require rapid referral to specialized nephrology teams regardless of age 5.

Transition Considerations

• The adolescent/young adult period (ages 14-24 years) represents a critical transition phase requiring special consideration for both nephrotic and nephritic syndromes 1

• Approximately 25% of teenagers and young adults with chronic kidney disease present primarily to adult services, usually after age 16 in developed countries 1

• This age group exhibits increased risk-taking behavior and non-adherence issues related to brain development and maturation 1