A 45-year-old man with IgA nephropathy (Oxford MEST-C classification: M1, E1, S1, T1, C1) has proteinuria 2.8 g/day and eGFR 52 mL/min. He is on ACE inhibitor. According to the TESTING trial and current KDIGO 2021 guidelines, what is the recommended additional therapy?
- A Immunosuppression with mycophenolate mofetil alone
- B SGLT2 inhibitor (dapagliflozin) to reduce proteinuria and slow CKD progression ✓
- C Low-dose corticosteroids (0.5 mg/kg/day for 6 months) if eGFR >30 after optimizing RAS blockade
- D Rituximab infusion for MEST-C high-risk features
Explanation
SGLT2 inhibitors (dapagliflozin, empagliflozin, canagliflozin) have been shown in the DAPA-CKD trial to significantly reduce composite renal outcomes in CKD patients with proteinuria, including IgA nephropathy (pre-specified subgroup). KDIGO 2021 CKD guidelines and the IgA Nephropathy guidelines now recommend SGLT2 inhibitors as add-on therapy for IgA nephropathy with persistent proteinuria >0.5 g/day after RAS blockade optimization. The TESTING trial (methylprednisolone vs placebo) showed benefit but also significant adverse effects (infections, metabolic). Sparsentan (dual endothelin-angiotensin receptor antagonist) and targeted budesonide (Nefecon) are newer approved options. Rituximab has no proven role.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.