315) A 64-year-old man with history of diabetes mellitus is evaluated in your office during a follow-up visit . He was admitted to the hospital one week ago because of incidentally discovered high serum potassium of 7.0mEq/L on his routine labs. He has history of hypertension and Stage I chronic kidney disease . His medications prior to the hospital admission included glyburide and enalapril. However, Enalapril was discontinued and he was started on hydrochlorthiazide during that admission. He denies any complaints at this time. A serum potassium level is 4.5mEq/l , serum creatinine 1.8mg% and urinalysis reveals proteinuria. 24 hour urine collection reveals 300mg proteinuria/24hrs. Which of the following is the most appropriate next step?
A) Re-start Enalapril at 50% of previous dose
B) Start Losartan
C) Start Hydralazine and Isosorbide
D) Start Spironolactone
E) Renal biopsy