Case
Angiotensin II receptor blockers (ARBs) effectively reduce urinary protein. An increase in aldosterone after ARB is termed aldosterone breakthrough and mineralocorticoid receptor antagonists (MRAs) are useful against this phenomenon. The Japanese traditional medicine saireito has the potential to reduce proteinuria. MRAs may suppress licorice‐induced pseudoaldosteronism.
Outcome
A 25‐year‐old Japanese female with idiopathic membranous nephropathy developed anasarca and a urinary protein/urinary creatinine ratio of 6.07. Her serum albumin level was 1.0 g/dL. Prednisolone, ciclosporin, and the ARB losartan were prescribed. After four months, prednisolone was tapered from 50 to 20 mg, and urinary protein/creatinine mildly decreased to 2.2. Although proteinuria was not reduced after the addition of the MRA eplerenone, further addition of saireito markedly reduced her proteinuria to 0.31. The serum albumin increased to over 3.0 g/dL.
Conclusion
The combination of ARB, MRA, and saireito may exert a therapeutic effect and reduce the proteinuria due to nephrotic syndrome in membranous nephropathy.