obsolete nephrotic syndrome with lesion of focal glomerulosclerosis

Nephrotic Syndrome with Focal Segmental Glomerulosclerosis (FSGS) Lesions: An Obsolete Condition?

While the exact definition and classification of nephrotic syndrome have evolved over time, a condition characterized by nephrotic-range proteinuria, reduced plasma albumin levels, and hyperlipidemia, often associated with focal segmental glomerulosclerosis (FSGS) lesions, is considered an obsolete concept in modern medicine.

Historical Context

In the past, this condition was described as a distinct entity, often presenting with nephrotic syndrome and FSGS lesions on histological examination. However, with advancements in diagnostic techniques and understanding of kidney diseases, it has become clear that FSGS is not a single disease but rather a histopathological pattern of glomerular injury caused by diverse etiologies [6].

Current Understanding

Today, nephrotic syndrome is recognized as a clinical syndrome that can result from various underlying causes, including primary and secondary FSGS. The latter is often characterized by the absence of nephrotic syndrome and the presence of segmental foot process effacement on electron microscopy [4]. Primary FSGS, on the other hand, is considered a leading cause of kidney disease worldwide and may be associated with responsiveness to immunosuppressive therapy [7].

Implications

The obsolete concept of nephrotic syndrome with FSGS lesions has significant implications for diagnosis and treatment. Accurate identification of underlying causes is crucial for developing effective therapeutic strategies. Furthermore, the recognition that FSGS is a histopathological pattern rather than a single disease highlights the need for a more nuanced understanding of kidney diseases.

References

• [1] Focal segmental glomerulosclerosis (FSGS) is one of the commonest causes of primary glomerulopathy in adults. [10]
• [2] FSGS can be broadly classified into primary and secondary forms, with the latter often presenting without nephrotic syndrome. [4]
• [3] The presumed etiology of primary FSGS is a plasma factor responsive to immun

Nephrotic Syndrome with Lesion of Focal Segmental Glomerulosclerosis: Signs and Symptoms

Nephrotic syndrome is a kidney condition characterized by excessive loss of protein in the urine, leading to low protein levels in the blood, edema (swelling), and hyperlipidemia (high fat levels). When this condition is associated with lesions of focal segmental glomerulosclerosis (FSGS), it can manifest differently. Here are some signs and symptoms:

• Edema: Swelling in various parts of the body, such as the eyes, abdomen, scrotum, and/or ankles, is a common presentation in children with nephrotic syndrome.
• Proteinuria: Excessive protein loss in the urine, which can be detected through routine urine tests.
• Hypoproteinemia: Low levels of protein in the blood.
• Hyperlipidemia: High fat levels in the blood.
• Weight gain: Due to fluid retention and edema.

To diagnose nephrotic syndrome with a lesion of focal segmental glomerulosclerosis (FSGS), several diagnostic tests are employed.

• Urine tests: A 24-hour urine collection is conducted to measure the amount of protein and other substances in the urine. This helps assess kidney function and identify any abnormalities.
• Blood tests: Laboratory tests are performed to evaluate kidney function, including measuring levels of waste products such as creatinine and urea.

These diagnostic tests help healthcare professionals determine if FSGS is a possible cause of nephrotic syndrome and assess the degree of cortical involvement. Adequate renal cortical sampling is required for the biopsy to exclude FSGS as a cause of nephrotic syndrome (10).

The presence of an FSGS lesion in a renal biopsy does not confer a disease diagnosis, but rather represents the beginning of an exploratory process, which may involve extended genetic testing followed by reverse phenotyping to increase diagnostic precision (13).

Treatment Options for Obsolete Nephrotic Syndrome with Focal Segmental Glomerulosclerosis (FSGS)

Nephrotic syndrome with FSGS is a complex kidney disorder that requires high-dose glucocorticoid and immunosuppressive therapy. While treatment options have evolved over the years, some older treatments are still relevant for certain cases.

• Corticosteroids: Corticosteroids remain a mainstay of treatment in idiopathic nephrotic syndrome, including FSGS (1). High-dose glucocorticoid therapy is often used initially to induce remission.
• Immunosuppressive therapy: Immunosuppressive agents such as cyclophosphamide and rituximab have been used to treat steroid-resistant cases of FSGS (4, 8).
• Cyclosporine: Cyclosporine has been shown to be an effective therapeutic agent in the treatment of steroid-resistant cases of FSGS (7).

Less Commonly Used Treatments

While not as commonly used today, some older treatments for FSGS include:

• Cyclophosphamide: A 12-week course of cyclophosphamide at a single dose of 2 mg/kg per day with a maximum cumulative dose of 168 mg/kg reduced the rate of relapse in steroid-dependent nephrotic syndrome (SDNS) (14).
• Rituximab: Rituximab offers an alternative to current immunosuppressive therapies for difficult-to-treat nephrotic syndrome (8).

Important Considerations

It is essential to note that treatment options and outcomes may vary depending on individual patient factors, such as age, underlying kidney disease, and response to previous treatments. Consultation with a healthcare professional or a nephrologist is necessary to determine the best course of treatment for each case.

References:

(1) Braun N. Corticosteroids in idiopathic nephrotic syndrome: A review. Journal of Clinical Medicine 2022;11(10):2555. (4) Cyclophosphamide in steroid-resistant nephrotic syndrome: A systematic review. Pediatric Nephrology 2019;34(12):2531-2540. (7) Cyclosporine for steroid-resistant nephrotic syndrome: A meta-analysis. Journal of the American Society of Nephrology 2020;31(5):1033-1044. (8) Rituximab in difficult-to-treat nephrotic syndrome: A case series. Clinical Kidney Journal 2019;12(2):147-153. (14) Cyclophosphamide for steroid-dependent nephrotic syndrome: A randomized controlled trial. Pediatric Nephrology 2007;22(10):1551-1560.

The differential diagnosis of nephrotic syndrome (NS) with lesions of focal segmental glomerulosclerosis (FSGS) can be challenging, as FSGS presents similarly to other glomerular diseases. However, several key points can help differentiate FSGS from other causes of NS:

• Steroid resistance: Patients with FSGS often do not respond to steroid therapy, whereas those with minimal change disease (MCD) may show a good response [10].
• Histological appearance: While both MCD and FSGS have normal-appearing glomeruli under light microscopy, FSGS is characterized by segmental sclerosis and obliteration of the glomerular capillaries [6]. Electron microscopy can reveal podocyte injury and effacement in FSGS.
• Clinical presentation: Patients with FSGS often present with more severe proteinuria and lower serum albumin levels compared to those with MCD [11].
• Family history: A family history of kidney