Clinical Case Presentation 3 A 55-year-old man with long-standing diabetes is referred for evaluation and treatment of diabetic nephropathy. His only medication is celecoxib 200 mg/day for treatment of mild degenerative joint disease. Physical examination is significant for a blood pressure of 146/92 mmHg and trace pedal edema. Laboratory test results show Na+ 142 mmol/L, K+ 5.7 mmol/L, Cl– 108 mmol/L, HCO3– 18 mmol/L, serum creatinine 2.0 mg/dL, protein 4.6 g/24 h, and an arterial blood gas test shows pH 7.5 and pCO2 33 mmHg. His primary care physician has been reluctant to start either an angiotensin-converting enzyme (ACE) inhibitor or an angiotensin II receptor blocker (ARB) because of increased serum K+ concentrations.