From the Guidelines
Nephritis should be treated with immunosuppressive agents, such as mycophenolate mofetil (MMF) or cyclophosphamide, in combination with glucocorticoids, to reduce proteinuria and preserve kidney function, as recommended by the 2020 EULAR/ERA-EDTA guidelines 1.
Key Recommendations
- Kidney biopsy should be considered when there is evidence of kidney involvement, especially in the presence of persistent proteinuria ≥0.5 g/24 hours or an unexplained decrease in GFR 1.
- The use of the International Society of Nephrology/Renal Pathology Society (ISN/RPS) 2003 classification system is recommended for pathological assessment of kidney biopsy, with additional assessment of activity and chronicity indices, as well as thrombotic and vascular lesions associated with anti-phospholipid antibodies/syndrome 1.
- Immunosuppressive agents, such as MMF or cyclophosphamide, are recommended in combination with glucocorticoids for the treatment of class IIIA or IIIA/C (±V) and IVA or IV A/C (±V) nephritis, with the goal of achieving a complete clinical response, defined as a reduction in proteinuria of at least 50% and a UPCR target below 500-700 mg/g by 12 months 1.
Treatment Options
- MMF (target dose: 2 to 3 g/day) or low-dose intravenous cyclophosphamide (500 mg every 2 weeks for a total of 6 doses) in combination with glucocorticoids are recommended as initial treatment for patients with class III or IV (±V) lupus nephritis, due to their best efficacy/toxicity ratio 1.
- Combination of MMF (target dose: 1 to 2 g/day) with a calcineurin inhibitor (CNI), such as tacrolimus, is an alternative treatment option, particularly in patients with nephrotic-range proteinuria 1.
- Hydroxychloroquine (HCQ) should be coadministered, at a dose not to exceed 5 mg/kg/day, to improve outcomes by reducing renal flares and limiting the accrual of renal and cardiovascular damage 1.
Monitoring and Follow-up
- Patients with lupus nephritis should be regularly monitored by determining body weight, blood pressure, serum creatinine, and eGFR, as well as serum albumin, proteinuria, and urinary sediment, to assess disease activity and response to treatment 2.
- Repeat renal biopsy may be considered in selected cases, such as worsening or refractoriness to immunosuppressive or biological treatment, to demonstrate change or progression in histological class, change in biopsy chronicity and activity indices, and to provide prognostic information 2.
From the Research
Definition and Classification of Nephritis
- Nephritis refers to a group of disorders that present with a combination of haematuria, proteinuria, hypertension, and reduction in kidney function to a variable degree 3
- It can be classified into different types, including immune-complex glomerulonephritis, anti-neutrophil cytoplasmic antibodies-associated glomerulonephritis, anti-glomerular basement membrane glomerulonephritis, C3 glomerulopathy, and monoclonal immunoglobulin-associated glomerulonephritis 3
Clinical Presentation of Nephritis
- The clinical presentation of nephritis can vary, with some patients presenting with asymptomatic haematuria and proteinuria, while others may present with full-blown nephritic syndrome or rapidly progressive glomerulonephritis 3
- The nephritic syndrome is associated with hematuria and proteinuria and abnormal kidney function and carries a poorer prognosis and is typically associated with hypertension 4
Treatment of Nephritis
- The treatment of nephritis depends on the underlying cause and severity of the disease, but may include non-specific measures aimed at controlling hypertension, edema, proteinuria, and disease-modifying immunosuppression 4
- Mycophenolate mofetil (MMF) has been shown to be effective in the treatment of lupus nephritis, with a significant improvement in serum albumin and a decrease in proteinuria 5, 6
- MMF has also been compared to cyclophosphamide in the treatment of severe IgA nephropathy, with MMF showing a higher remission rate and a lower incidence of adverse effects 7
Diagnosis of Nephritis
- The gold standard for the diagnosis of nephritis is a kidney biopsy, with a hallmark glomerular inflammation that translates into various histopathological patterns depending on the location and severity of the glomerular injury 3
- The diagnosis of nephritis can also be made based on clinical presentation, laboratory tests, and imaging studies, but a kidney biopsy is necessary to confirm the diagnosis and guide treatment 3