Most common nephrotic syndrome in elderly patients

Ans. b (Membranous GN) (Ref H-17th/1791)# MEMBRANOUS GN accounts for approx 30% of cases of nephrotic syndrome in adults with peak incidence between 30-50 yrs age.# It is rare in childhood and by far the most common cause of nephrotic syndrome in the elderly# In 25-30% of cases, MGN is secondary to malignancy (solid tumors of the breast, lung, colon), infection (hepatitis B, malaria, schistosomiasis), or rheumatologic disorders like lupus or rarely rheumatoid arthritis.# Male to female ratio of 2:1.MEMBRANOUS GLOMERULONEPHRITISA. Primary/idiopathic membranous glomerulonephritisB. Secondary membranous glomerulonephritis1. Infection: Hepatitis B and C, syphilis, malaria, schistosomiasis, leprosy, filariasis2. Cancer: Breast, colon, lung, stomach, kidney, esophagus, neuroblastoma3. Drugs: gold, mercury, penicillamine, nonsteroidal anti-inflammatory agents, probenecid4. Autoimmune diseases: systemic lupus erythematosus, rheumatoid arthritis, primary biliary cirrhosis, dermatitis herpetiformis, bullous pemphigoid, myasthenia gravis, Sjogren's syndrome, Hashimoto's thyroiditis5. Other systemic diseases: Fanconi's syndrome, sickle cell anemia, diabetes, Crohn's disease, sarcoidosis, Guillain- Barre syndrome, Weber-Christian disease, angiofollicular lymph node hyperplasia# Uniform thickening of the BM along the peripheral capillary loops is seen by light microscopy on renal biopsy.# Immunofluorescence demonstrates diffuse granular deposits of IgG and C3, and electron microscopy typically reveals electron-dense subepithelial deposits.# Eighty percent of patients with MGN present with nephrotic syndrome and nonselective proteinuria. Microscopic hematuria is seen in up to 50% of patients. Spontaneous remissions occur in 20-33% of patients and often occur late in the course after years of nephrotic syndrome. One-third of patients continue to have relapsing nephrotic syndrome.# Although thrombotic complications are a feature of all nephrotic syndromes, MGN has the highest reported incidences of renal vein thrombosis, pulmonary embolism, and deep vein thrombosis.# Rx: In addition to the Rx of edema, dyslipidemia, and hypertension, inhibition of the renin-angiotensin system is recommended.Recommendations based on small clinical studies are to treat with steroids and cyclophosphamide, chlorambucil, or cyclosporine.Additional Educational Points# The renal lesions most commonly seen, in order of decreasing frequency, are cryoglobulinemic glomerulonephritis, MGN, and Type I MPGN.# All cases with borderline lepromatous and lepromatous types of leprosy have various forms of glomerulonephritis. Most common is focal glomerulonephritis followed by mesangioproliferative glomerulonephritis or renal amyloidosis.