ACE and idiopathic membranous glomerulonephritis: We have studied the effects of add-on spironolactone treatment (100 mg/day) in 11 patients with idiopathic membranous nephropathy (IMN) and >3 gm proteinuria/day despite angiotensin converting enzyme (ACE) inhibitor therapy titrated to a systolic/diastolic blood pressure <120/80 mmHg.