From the Guidelines
Nephrotic syndrome is primarily caused by damage to the glomerular filtration barrier, resulting in significant protein leakage into urine, whereas nephritic syndrome results from inflammation within the glomeruli, characterized by hematuria, hypertension, and mild proteinuria. The causes of these two syndromes can be distinguished based on their underlying pathophysiology. Nephrotic syndrome is commonly caused by minimal change disease, focal segmental glomerulosclerosis, membranous nephropathy, diabetic nephropathy, and amyloidosis, as well as certain medications like NSAIDs and infections such as HIV and hepatitis 1. On the other hand, nephritic syndrome is caused by inflammation within the glomeruli, with common causes including post-streptococcal glomerulonephritis, IgA nephropathy, lupus nephritis, Goodpasture syndrome, and ANCA-associated vasculitis.
Key Causes of Nephrotic Syndrome
- Minimal change disease
- Focal segmental glomerulosclerosis
- Membranous nephropathy
- Diabetic nephropathy
- Amyloidosis
- Certain medications like NSAIDs
- Infections such as HIV and hepatitis
Key Causes of Nephritic Syndrome
- Post-streptococcal glomerulonephritis
- IgA nephropathy
- Lupus nephritis
- Goodpasture syndrome
- ANCA-associated vasculitis
The distinction between these two syndromes is crucial for proper diagnosis and treatment, as their underlying causes and pathophysiology differ significantly. According to the KDIGO 2021 clinical practice guideline for the management of glomerular diseases, understanding the causes of nephrotic and nephritic syndrome is essential for providing effective treatment and improving patient outcomes 1. The most recent and highest quality study, the KDIGO 2021 guideline, provides a comprehensive overview of the causes and management of glomerular diseases, including nephrotic and nephritic syndrome.
From the Research
Causes of Nephrotic Syndrome (NS)
- Nephrotic syndrome is often associated with hyperlipidaemia, thromboembolism and an increased risk of infection, and develops following pathological injury to renal glomeruli 2.
- The most common cause in children is minimal change glomerulonephritis, while in white adults, nephrotic syndrome is most frequently due to membranous nephropathy 2.
- In populations of African ancestry, the most common cause of nephrotic syndrome is focal segmental glomerulosclerosis 2.
- Diabetic nephropathy is the most common multisystem disease that can cause nephrotic syndrome 2.
Causes of Nephritic Syndrome (NiS)
- The nephritic syndrome is associated with hematuria and proteinuria and abnormal kidney function and carries poorer prognosis and is typically associated with hypertension 3.
- The most common causes of nephritic syndrome are post infectious GN, IgA nephropathy and lupus nephritis 3.
- Chronic GN is slowly progressive and is associated with hypertension and gradual loss of kidney function 3.
Comparison of NS and NiS
- Nephrotic syndrome is defined by the presence of heavy proteinuria, hypoalbuminemia, and peripheral edema, while nephritic syndrome is defined by the presence of hematuria, proteinuria, and abnormal kidney function 3.
- The treatment of NS and NiS includes non-specific measures aimed at controlling hypertension, edema, proteinuria and disease modifying immunosuppression 3.
- In children, most cases of NS are due to minimal change disease, which is responsive to steroid treatment, while in adults, biopsy typically is indicated for diagnosis, except in patients with positive test results for serum anti-phospholipase A2 receptor antibodies 4.
Pathophysiology of NS
- Minimal change nephrotic syndrome (MCNS) is the most common cause of the nephrotic syndrome in children, and is thought to reflect a disorder of T-lymphocytes, which release a cytokine that injures the glomerular epithelial cells 5.
- Focal segmental glomerulosclerosis (FSGS) is characterized by an increased number of large pores in the glomerular basement membrane, leading to an impairment in size selectivity 5.
- The presence of glomerular hypertrophy in biopsies of apparent MCNS appeared to be a high specific indicator of increased risk for progression to FSGS 5.