Which of the following is the most common cause of nephrotic syndrome in Indian adults?

Explanation

## Epidemiology of Nephrotic Syndrome in India **Key Point:** Membranous nephropathy is the most common cause of nephrotic syndrome in Indian adults, accounting for approximately 40–50% of cases. ### Geographic and Age-Related Patterns | Cause | Prevalence in Adults (India) | Prevalence in Children | Key Features | |-------|------------------------------|----------------------|---------------| | Membranous nephropathy | 40–50% | <5% | Most common adult cause; idiopathic or secondary | | FSGS | 15–20% | 10–15% | Second most common; associated with obesity, HTN | | MPGN | 10–15% | 5–10% | Often secondary to infection or autoimmune disease | | Minimal change disease | <5% | 85–90% | Most common in children; excellent prognosis | **High-Yield:** In Indian populations, membranous nephropathy predominates in adults, whereas minimal change disease is the leading cause in children. This geographic variation is important for exam recall. ### Membranous Nephropathy — Key Features - **Pathology:** Subepithelial immune complex deposition; "spike and dome" appearance on electron microscopy. - **Idiopathic vs. Secondary:** ~70% idiopathic in India; ~30% secondary to malignancy, SLE, infections (TB, hepatitis B). - **Clinical presentation:** Insidious onset; heavy proteinuria (>3.5 g/day); hypoalbuminemia; edema. - **Prognosis:** Variable; ~30–40% spontaneous remission; ~40% chronic kidney disease progression. **Clinical Pearl:** Always screen for malignancy (especially lung, GI, breast) and hepatitis B/C in adults with membranous nephropathy, as secondary causes are common in India. ### Why Other Options Are Less Common in Adults - **Minimal change disease:** Predominantly pediatric (85–90% of childhood nephrotic syndrome); rare in adults (<5%). - **FSGS:** Second most common; rising prevalence due to obesity and hypertension epidemiology. - **MPGN:** Often secondary; less common as primary cause of nephrotic syndrome in India.