From the Guidelines
Nephritic syndrome and nephrotic syndrome are two distinct kidney disorders with different causes, and their diagnosis and treatment depend on understanding these underlying causes. Nephritic syndrome is primarily caused by inflammatory processes affecting the glomeruli, with common causes including post-streptococcal glomerulonephritis following a streptococcal infection, IgA nephropathy, lupus nephritis, Goodpasture syndrome, and ANCA-associated vasculitis, as outlined in the 2021 KDIGO clinical practice guideline for the management of glomerular diseases 1. These conditions trigger immune complex deposition or direct antibody damage to the glomerular basement membrane, leading to hematuria, proteinuria, and often hypertension and reduced kidney function. Some key causes of nephritic syndrome include:
- Post-streptococcal glomerulonephritis
- IgA nephropathy
- Lupus nephritis
- Goodpasture syndrome
- ANCA-associated vasculitis Nephrotic syndrome, conversely, results from damage to the podocytes that maintain the glomerular filtration barrier, causing massive protein leakage into urine. Common causes include minimal change disease (especially in children), focal segmental glomerulosclerosis, membranous nephropathy, diabetic nephropathy, and amyloidosis, with the Canadian Society of Nephrology commentary on the 2012 KDIGO clinical practice guideline for glomerulonephritis providing insight into the management of these conditions 1. Nephrotic syndrome presents with severe proteinuria (>3.5g/day), hypoalbuminemia, edema, and hyperlipidemia. Some key causes of nephrotic syndrome include:
- Minimal change disease
- Focal segmental glomerulosclerosis
- Membranous nephropathy
- Diabetic nephropathy
- Amyloidosis The distinction between these syndromes is important for proper diagnosis and treatment, though some kidney diseases can present with features of both conditions simultaneously, and the 2021 KDIGO guideline provides updated recommendations for the management of glomerular diseases, including the use of immunosuppressive therapy and supportive therapies 1.
From the Research
Nephritic Syndrome
- Nephritic syndrome is characterized by a constellation of hematuria, proteinuria, hypertension, and in some cases acute kidney injury and fluid retention, typically resulting from acute glomerulonephritis 2.
- The most common diseases associated with nephritic syndrome include:
- Infection-related glomerulonephritis
- IgA nephropathy
- Lupus nephritis
- Membranoproliferative glomerulonephritis
- Antineutrophil cytoplasmic antibody-associated vasculitis 2
- Acute post-streptococcal glomerulonephritis (APSGN) is a major cause of acute glomerulonephritis in children, often presenting as acute nephritic syndrome 3.
Nephrotic Syndrome
- Nephrotic syndrome is typically characterized by heavy proteinuria, hypoalbuminemia, hyperlipidemia, and edema 4, 5, 6.
- The primary causes of nephrotic syndrome include:
- Minimal change disease (MCD)
- Focal segmental glomerulosclerosis (FSGS)
- Membranous nephropathy
- Membranoproliferative glomerulonephritis
- IgA nephropathy
- Fibrillary glomerulonephritis
- Amyloidosis
- Monoclonal gammopathy of renal significance 4
- MCD and FSGS are the two major causes of nephrotic syndrome in children and young adults, with both diseases resembling each other and sometimes only being discriminated based on their clinical courses 5.
- Idiopathic membranous nephropathy and primary FSGS usually present with a nephrotic syndrome with or without renal insufficiency 6.