What are the management options for Immunoglobulin A (IgA) nephropathy with worsening renal function, also known as Impaired renal function?

From the Guidelines

Management of IgA nephropathy with worsening kidney function should prioritize a multi-faceted approach, focusing on optimizing blood pressure control with ACE inhibitors or ARBs, and considering the addition of SGLT2 inhibitors, as supported by the most recent evidence from 2023 1. The first-line treatment should focus on optimizing blood pressure control with ACE inhibitors or ARBs, targeting blood pressure <130/80 mmHg, with medications like lisinopril 10-40 mg daily or losartan 50-100 mg daily commonly used. Key considerations in management include:

• Optimizing blood pressure control with ACE inhibitors or ARBs
• Considering the addition of SGLT2 inhibitors, such as dapagliflozin 10 mg daily or empagliflozin 10-25 mg daily, to slow progression of kidney disease, regardless of diabetes status, as shown in studies like DAPA-CKD 1
• Dietary sodium restriction (<2 g/day) and protein moderation (0.8 g/kg/day) as important supportive measures
• Fish oil supplements (3-4 g/day) may provide additional benefit in reducing proteinuria, as suggested by the Canadian Society of Nephrology commentary on the 2012 KDIGO clinical practice guideline for glomerulonephritis 1 Regular monitoring of kidney function, proteinuria, and blood pressure every 3-6 months is essential to assess treatment response, with the goal of reducing glomerular pressure, decreasing inflammation, and minimizing immune complex deposition in the glomeruli, thereby protecting kidney function from further deterioration. Immunosuppressive therapy may be considered for patients with proteinuria >1 g/day and declining GFR, with regimens combining alkylating agents with glucocorticoids or anti-CD20 agents like rituximab potentially effective, but requiring individualized risk-benefit analysis, patient preference, and local availability, as discussed in the KDOQI US commentary on the 2021 KDIGO clinical practice guideline for the management of glomerular diseases 1.

From the Research

Management of IgA Nephropathy with Worsening Kidney Function

• The management of IgA nephropathy with worsening kidney function involves a combination of supportive care and immunosuppressive therapy 2, 3, 4, 5.
• Supportive care includes the use of renin-angiotensin system inhibitors, such as ACE inhibitors and angiotensin II receptor blockers, to reduce proteinuria and slow the progression of kidney disease 6, 2, 3.
• Immunusuppressive therapy, such as corticosteroids, may be used in patients with proteinuric IgA nephropathy, but the benefits and risks of such therapy must be carefully considered 2, 3, 4.
• Newer therapies, such as sodium-glucose transporter-2 inhibitors, sparsentan, and nefecon, have shown promise in reducing proteinuria and preserving kidney function in patients with IgA nephropathy 4, 5.
• Lifestyle modifications, such as protein and salt restriction, and blood pressure control, are also important in slowing the progression of kidney disease in patients with IgA nephropathy 2, 3, 5.

Treatment Approaches

• The treatment approach for IgA nephropathy with worsening kidney function depends on the severity of the disease and the presence of other complications, such as hypertension and proteinuria 3, 4, 5.
• Patients with mild disease and minimal proteinuria may be managed with supportive care alone, while those with more severe disease may require immunosuppressive therapy 3, 4.
• The use of corticosteroids and other immunosuppressive agents should be carefully considered, as they can have significant side effects 2, 3, 4.
• Newer therapies, such as complement inhibitors and immunomodulators, are being developed and may offer additional treatment options for patients with IgA nephropathy in the future 4, 5.

Future Directions

• Further research is needed to fully understand the pathogenesis of IgA nephropathy and to develop effective treatments for this disease 4, 5.
• The use of surrogate outcome markers, such as changes in proteinuria and estimated glomerular filtration rate, may help to accelerate the development of new therapies for IgA nephropathy 4.
• A personalized approach to treatment, taking into account the individual patient's disease characteristics and response to therapy, may help to optimize outcomes in patients with IgA nephropathy 2, 4.