Which medication class provides renal protection and reduces proteinuria in membranous nephropathy?

• A. Beta-blockers
• B. ACE inhibitors or ARBs
• C. Calcium channel blockers
• D. Diuretics

Answer: (B)

The key idea is that protecting kidney function in proteinuric nephropathies comes from lowering intraglomerular pressure to reduce protein leakage. Drugs that block the renin-angiotensin system achieve this by dilating the efferent arteriole of the glomerulus, which lowers the pressure inside the glomerular capillaries and markedly decreases proteinuria.

ACE inhibitors block the formation of angiotensin II, while ARBs block its receptor. Both actions reduce glomerular capillary pressure and the amount of protein that leaks into the urine, and they also lower systemic blood pressure, providing additional renal protection.

Other antihypertensives can lower blood pressure but don’t specifically reduce intraglomerular pressure or proteinuria to the same extent, so they’re less effective at renoprotection in membranous nephropathy. Diuretics help manage edema and volume status but don’t have the same antiproteinuric, nephroprotective effect.