Clinical course and outcome of adult patients with primary focal segmental glomerulosclerosis with kidney function loss on presentation

Abstract

BACKGROUND

Kidney function loss or renal insufficiency indicated by elevated creatinine levels and/or an estimated glomerular filtration rate (eGFR) < 60 mL/minute/1.73 m² at presentation in patients with primary focal segmental glomerulosclerosis (FSGS) is commonly seen as a poor prognostic marker for kidney survival. However, a pre>vious study from our center suggested this may be due to hemodynamic factors.

AIM

To observe the clinical and biochemical parameters, treatment response, kidney survival, and overall outcomes of adult patients with primary FSGS presenting with kidney function insufficiency.

METHODS

This retrospective observational study was conducted at the Department of Nephrology, Sindh Institute of Urology and Transplantation, Karachi, Pakistan, from January 1995 to December 2017. During this period, 401 biopsy-proven primary FSGS patients were identified, of which 98 (24.4%) presented with kidney function loss or renal insufficiency defined as eGFR < 60 mL/minute/1.73 m² at presentation and were studied in detail.

RESULTS

Among the 98 patients with renal function loss on presentation, the mean age was 30.9 years ± 13.6 years with a male-to-female ratio of 2.5:1. The mean serum creatinine level was 2.2 mg/dL ± 1.3 mg/dL and mean eGFR 37.1 mL/minute/1.73 m² ± 12.8 mL/minute/1.73 m². The mean 24-hour urinary protein excretion was 5.9 g/day ± 4.0 g/day, and the mean serum albumin was 2.1 g/dL ± 1.0 g/dL (median: 1.5 g/dL). The mean systolic blood pressure (BP) was 132.7 mmHg ± 19.8 mmHg, and the mean diastolic BP was 87.4 mmHg ± 12.7 mmHg. Steroid treatment was given to 81 (82.6%) of 98 patients for an average duration of 19.9 weeks ± 14.4 weeks, with a mean total steroid dose of 4.4 g ± 1.5 g. Treatment response showed that 20 (24.6%) patients achieved complete remission, 9 (11.1%) achieved partial remission, and 52 (64.1%) did not respond. The baseline eGFR was significantly lower in the non-responsive group (P = 0.006). The distribution of FSGS variants was also significantly different among steroid-responsive and non-responsive groups (P = 0.012).

CONCLUSION

Renal function loss in FSGS patients at presentation does not necessarily indicate irreversible kidney function loss and a significant number of patients respond to appropriate treatment of the underlying disease.

Key Words: Focal segmental glomerulosclerosis; Kidney function; Serum creatinine; Treatment response; Steroid therapy

Core Tip: Focal segmental glomerulosclerosis is a common glomerular disease that typically presents with nephrotic syndrome. It often presents with kidney function loss and generally signifies a poor prognosis. We previously showed that kidney function loss at presentation is not necessarily associated with poor outcomes. This study further corroborates these findings and suggests that treatment of such patients can improve outcomes.

INTRODUCTION

Focal segmental glomerulosclerosis (FSGS) is a clinicopathological syndrome characterized by variable levels of proteinuria (usually in the nephrotic range) and histopathologically by focal and segmental scarring of glomeruli, along with effacement of foot processes[1]. First described in 1957 by Rich in an autopsy series, FSGS is a common cause of nephrotic syndrome (NS), accounting for 40% of primary glomerulonephritis cases among adults and the second most common cause of NS in the pediatric population. The estimated incidence of FSGS in adults is approximately 7 per million population per year. The incidence varies by region and population demographics, with higher rates observed in certain ethnic groups, such as African Americans compared to Caucasians[2,3].

Over the past decade, the number of patients with FSGS has increased, making it the most frequent primary glomerulopathy leading to end-stage kidney disease[4,5]. Male sex, elevated creatinine levels or an estimated glomerular filtration rate (eGFR) < 60 mL/minute/1.73 m², and advanced stages of tubulointerstitial fibrosis at presentation are generally considered poor prognostic markers for kidney survival[6,7]. However, our previous study suggested that elevated serum creatinine was likely due to hemodynamic factors leading to reduced eGFR rather than chronic changes, and thus, increased serum creatinine levels alone did not adversely affect the outcome[8].

Despite recent advancements in the treatment of FSGS, including sodium-glucose transporter-2 inhibitors, angiotensin II/endothelin 2 receptor antagonists (Sparsentan), and anti-CD20 monoclonal antibody (Rituximab), prognosis still largely depends on baseline kidney function, the degree of global glomerulosclerosis, and the extent of tubulointerstitial fibrosis. A study showed that only 23.8% of patients with kidney function insufficiency (serum creatinine ≥ 1.4 mg/dL) achieved remission compared to 60% with normal kidney function[9,10]. Our previous publications indicated that elevated serum creatinine at presentation was not predictive of steroid responsiveness, suggesting that nephrologists should not be deterred from initiating steroid treatment, particularly in patients with a short duration of illness. Kidney function insufficiency is not a contraindication to treatment, as we have successfully treated many patients with steroids, resulting in either a decline or stabilization of serum creatinine levels[8].

This study aimed to observe the clinicopathological parameters and outcomes of adult patients with kidney function insufficiency at presentation in primary FSGS, assess their response to steroids, evaluate kidney survival, and describe the experiences from our center.

MATERIALS AND METHODS

This retrospective observational study was conducted at the Department of Nephrology, Sindh Institute of Urology and Transplantation (SIUT), Karachi, Pakistan, between January 1995 and December 2017. During this period, a total of 401 patients were diagnosed with primary FSGS. Among these, 98 (24.4%) patients had renal insufficiency or kidney function loss at presentation and were included in this study for detailed analysis. The majority of these patients, 81/98 (82.6%) were treated with steroids, as were 254/303 (83.8%) in those with normal renal function at presentation, as shown in Figure 1. The remaining few patients in both groups were treated with angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs) only.

Figure 1 Flow diagram showing the selection and analysis of the study participants. CR: Complete remission; FSGS: Focal segmental glomerulosclerosis; PR: partial remission.

The retrospective review included all consecutive adult patients (aged ≥ 17 years) with renal insufficiency who presented to the adult nephrology clinic of SIUT with a final diagnosis of primary FSGS and had at least 6 months of regular follow-up. Patients with known secondary causes of FSGS, including systemic diseases with glomerular involvement, acquired immunodeficiency syndrome, intravenous heroin abuse, solitary kidney, and urinary obstruction and/or reflux, were excluded.

The original biopsy reports and clinical records were reviewed to determine the patients’ age, sex, degree of proteinuria, blood pressure (BP), serum creatinine, total protein, and serum albumin. FSGS was diagnosed based on histopathologic examination, even with a single glomerulus displaying segmental or global sclerosis of tufts, according to standard criteria[8].

The clinical course, treatment responses, and final outcomes of each patient were evaluated by recording current medications, BP, serum creatinine and serum albumin levels, urine analysis, and 24-hour urinary protein excretion or spot urine for protein-creatinine ratio at appropriate follow-up visits.

All patients underwent percutaneous native kidney biopsies under real-time ultrasound guidance after informed consent. Light microscopy was performed with 10 serial sections, with levels 1, 5, and 10 stained by hematoxylin and eosin stain, level 7 by trichrome, level 8 by periodic acid-Schiff, and level 9 by Jones methenamine silver stain. FSGS was diagnosed according to established criteria by two experienced renal pathologists independently and then jointly to reach a consensus diagnosis[11]. The histological variants of FSGS were classified per the Columbia classification criteria[12]. In brief, the tip variant was diagnosed when at least one segmental lesion involved the tip location of the affected glomerulus (outer 25% of the tuft next to the beginning of the proximal tubule) (Figure 2A). It required the exclusion of collapsing and perihilar variants. The tubular pole needs to be identified in the defining lesion. The collapsing variant was diagnosed when at least one glomerulus showed segmental or global collapse and overlying podocyte hypertrophy and hyperplasia (Figure 2B). The defining criteria for perihilar variant included both of the following: (1) There must be at least one glomerulus with perihilar hyalinosis and/or sclerosis; and (2) > 50% of glomeruli with segmental lesions must have perihilar sclerosis and/or hyalinosis (Figure 2C). This category requires that the cellular variant, tip variant, and collapsing variant of FSGS be excluded. The cellular variant was defined by the presence of at least one glomerulus with endocapillary hypercellularity involving at least 25% of the tuft and causing obliteration of the capillary lumina (Figure 2D). Any segment (perihilar and/or peripheral) may be affected. This category requires that the tip variant and collapsing variant be excluded. FSGS, not otherwise specified (NOS), was diagnosed when at least one glomerulus revealed a segmental increase in the mesangial matrix obliterating the capillary lumina, with or without segmental capillary wall collapse but without associated podocyte hyperplasia (Figure 3). It required the exclusion of perihilar, cellular, tip, and collapsing variants.

Figure 2 Histopathological features of focal segmental glomerulosclerosis variants. A: Tip variant showing segmental scarring involving the tip domain of the glomerulus opposite the vascular pole (green arrow) [periodic acid-Schiff (PAS) stain, 400 ×]; B: Collapsing focal segmental glomerulosclerosis showing global collapse of capillary tufts associated with podocyte hypertrophy and hyperplasia [Jones Methenamine silver (JMS) stain, 200 ×]; C: Perihilar variant showing segmental scarring involving the vascular pole of the glomerulus (green arrow) (PAS stain, 400 ×); D: Cellular variant showing the expansion of a segment of glomerulus by endocapillary hypercellularity associated with mild podocyte hyperplasia (green arrow) (JMS stain, 400 ×).

Figure 3 Focal segmental glomerulosclerosis, not otherwise specified variant. The glomerulus is showing segmental scarring involving no specific location of the glomerulus and associated with adhesion to the Bowman’s capsule (green arrow). No podocyte hypertrophy or hyperplasia is noted (periodic acid-Schiff stain, 200 ×).

Immunofluorescence tissue specimens were stained using FITC-conjugated antisera specific for immunoglobulin (Ig) G, IgA, IgM, C3, and C1q (Dako, Glostrup, Denmark), as detailed in our earlier report[11]. Electron microscopy was performed on kidney biopsy specimens in selected patients.

NS was diagnosed according to standard criteria[8]. Hypertension was defined as BP readings exceeding 140 mmHg for systolic BP and 90 mmHg for diastolic BP in two consecutive measurements in the supine and sitting positions, or the need for antihypertensive drugs. Kidney function loss at presentation was defined per Kidney Disease: Improving Global Outcomes 2024 clinical practice guidelines for the diagnosis and evaluation of chronic kidney disease (CKD) as an eGFR < 60 mL/minute/1.73 m² in both sexes[13].

Standard therapeutic regimens and response definitions, with slight modifications, were used as in our previous study[11]. Briefly, all eligible patients were treated with prednisone at a dose of 1 mg/kg body weight per day for 6 weeks, followed by 0.75 mg/kg per day for 6 additional weeks, which was then gradually tapered over 3 months to complete 6 months of treatment. Complete remission (CR) was defined as a decrease in the rate of proteinuria to ≤ 0.2 g/day for at least 1 month, with serum creatinine persistently < 1.4 mg/dL. Partial remission (PR) was defined as a decrease in the rate of urinary protein excretion to between 0.21 g/day and 2 g/day for at least 1 month, with serum creatinine < 1.4 mg/dL. Time to remission was calculated from the date of treatment administration to the date of remission. Relapse was defined as the recurrence of nephrotic-range proteinuria and edema during steroid tapering or after stopping treatment. Relapses received a second course of steroid treatment in combination with cyclosporine. Kidney failure (KF) and KF with replacement therapy (referred to as KFRT) were defined per standard criteria[8].

Statistical analysis

Data were entered and analyzed using Statistical Package for the Social Sciences, version 22 (IBM Corp., Armonk, NY, United States). Descriptive statistics summarized the continuous and categorical variables. Continuous variables were presented as mean and standard deviation or median and interquartile range, depending on the data distribution. Categorical variables were reported as frequencies and percentages. The χ² test was used to determine the proportion differences between the study groups for categorical variables. A student’s two-sample t-test was used to compare mean differences between treatment-responsive and treatment-resistant cases for continuous variables. Pearson’s correlation was used to find relationships, if any, between renal function loss and other clinical and laboratory findings at presentation. A P value less than 0.05 was considered significant.

RESULTS

A total of 401 biopsy-proven FSGS patients were identified during the study period, of which 98 (24.4%) had renal function loss at the time of presentation. The relevant baseline characteristics of these patients are shown in Table 1. The mean age was 30.9 years ± 13.6 years, with a male-to-female ratio of 2.5:1. The mean serum creatinine level was 2.2 mg/dL ± 1.3 mg/dL and mean eGFR 37.1 mL/minute/1.73 m² ± 12.8 mL/minute/1.73 m². The mean 24-hour urinary protein excretion was 5.9 g/day ± 4.0 g/day. The mean serum albumin level was 2.1 g/dL ± 1.0 g/dL (median: 1.5 g/dL). The mean systolic BP was 132.7 mmHg ± 19.8 mmHg, and the mean diastolic BP was 87.4 mmHg ± 12.7 mmHg.

Table 1 Demographic characteristics, clinical features, biochemical and histopathological results of adult patients of focal segmental glomerulosclerosis with kidney function loss at presentation, n = 98.

Parameters	Results
Age in years	30.9 ± 13.6
Sex as male:female	2.5:1
Systolic BP in mmHg	132.7 ± 19.8
Diastolic BP in mmHg	87.4 ± 12.7
Initial proteinuria in mg/24 hours	5945.1 ± 4007.9
Serum albumin in g/dL	2.1 ± 1.0
Serum creatinine in mg/dL	2.2 ± 1.3
Renal insufficiency in males	70 (71.4)
Renal insufficiency in females	28 (28.6)
Estimated glomerular filtration rate on presentation in mL/minute/1.73 m2	37.1 ± 12.8
Histopathological findings
Number of glomeruli	16.4 ± 8.2
Number of glomeruli with global sclerosis	3.4 ± 2.9
Number of glomeruli with segmental sclerosis	3.1 ± 3.0
Tubular atrophy
Mild	41 (41.8)
Moderate	11 (11.2)
Fibrointimal thickening of arteries
Mild	9 (4.2)
Moderate	4 (4.1)
Focal segmental glomerulosclerosis variants
Not otherwise specified	43 (43.9)
Tip	20 (20.4)
Collapsing	19 (19.4)
Hilar	1 (1.0)
Cellular	1 (1.0)
Unknown/unclassified	14 (14.3)

Data are n (%). BP: Blood pressure.

The relative percentages of FSGS variants were 44% for NOS, 20.4% for tip, 19.4% for collapsing, 1% for hilar, 1% for cellular, and 14.3% were unclassified/unknown variants. Moderate tubular atrophy was found in 11 (11.2%) patients, while mild tubular atrophy was present in 41.8% of cases. Fibro-intimal thickening was noted in less than 10% of cases (Table 1).

A total of 82.6% (81/98) of patients received steroid treatment with a mean duration of 19.9 weeks ± 14.4 weeks. The mean total steroid dose was 4.4 g ± 1.5 g. Due to reasons such as uncontrolled diabetes, intolerance to steroids, risk of osteoporosis, and other complications of immunosuppressive drugs, the remaining patients were treated with ACE inhibitors or ARBs only. Out of the 81 patients who received steroids, 20 (24.6%) patients achieved CR. PR was observed in 9 (11.1%) patients, while, 52 (64.1%) patients showed no response to treatment, highlighting the challenges in effectively managing this condition. The mean time to remission was 11.3 weeks ± 6.7 weeks (Table 2). A comparison of various clinicopathological parameters showed no statistically significant difference between steroid-responsive and non-responsive groups except for baseline eGFR, as shown in Table 3. There was no statistically significant difference between responders and non-responders in terms of age, sex, baseline BP, degree of proteinuria, duration of steroid treatment, or the cumulative dose of steroids (Table 3). However, the baseline eGFR was significantly lower in the non-responsive group (35.5 mL/minute/1.73 m² ± 11.2 mL/minute/1.73 m²) compared to the responsive group (43.2 mL/minute/1.73 m² ± 11.8 mL/minute/1.73 m²) (P = 0.006). Similarly, the distribution of FSGS variants was also significantly different among steroid-responsive and non-responsive groups (P = 0.012). The final eGFR showed a significant difference as well: 76.3 mL/minute/1.73 m² ± 34.5 mL/minute/1.73 m² in the responsive group and 49.8 mL/minute/1.73 m² ± 38.8 mL/minute/1.73 m² in the non-responsive group (P = 0.004) (Figure 4). The final serum creatinine levels after steroid treatment were inversely related to the final eGFR values, as shown in Figure 5.

Figure 4 Scatterbox charts comparing the final serum creatinine and estimated glomerular filtration rate values among the steroid-responsive and steroid-non-responsive groups after steroid treatment. A: The final serum creatinine; B: Estimated glomerular filtration rate (EGFR) values.

Figure 5 Scatter diagram showing an inverse relationship between serum creatinine and estimated glomerular filtration rate after steroid treatment. EGFR: Estimated glomerular filtration rate.

Table 2 Treatment responses and follow-up information of adult patients with primary focal segmental glomerulosclerosis with kidney function loss at presentation who received steroid treatment, n = 81.

Parameters	Results
Follow-up duration in weeks	136.8 ± 20.6
Total steroid dose in mg	4391.5 ± 1502.4
Duration of steroid treatment in weeks	19.9 ± 14.4
Time to remission in weeks	11.3 ± 6.7
Complete remission	20/81 (24.6)
Partial remission	9/81 (11.1)
No remission	52/81 (64.1)
Spontaneous remission	2 (2.4)

Data are n (%).

Table 3 Comparison of main demographic, clinical, and laboratory parameters among steroid-responsive and non-responsive adult patients with primary focal segmental glomerulosclerosis with kidney function loss at presentation and treated with steroids, n = 81.

Parameters	Steroid-responsive group, n = 29	Steroid non-responsive group, n = 52	P value
Age in years	32.9 ± 13.3	38.2 ± 15.2	0.123
Sex as male:female	3.8:1	2.1:1	0.251
Systolic BP in mmHg	132.1 ± 22.2	131.8 ± 18.6	0.946
Diastolic BP in mmHg	84.9 ± 13.2	87.5 ± 12.7	0.380
Initial protein in mg/24 hours	5161.9 ± 3615.2	5803.1 ± 3879.4	0.569
Serum albumin in g/dL	1.87 ± 1.06	2.05 ± 1.01	0.492
Serum creatinine in mg/dL	2.105 ± 1.81	2.20 ± 0.92	0.748
Estimated glomerular filtration rate on presentation in mL/minute/1.73 m2	43.2 ± 11.8	35.5 ± 11.2	0.006
Cumulative steroid dose in mg/kg	34.5 ± 32.1	48.4 ± 37.8	0.097
Duration of steroid use in weeks	22.8 ± 21.7	18.3 ± 7.9	0.180
Histopathological findings
Number of glomeruli	17.25 ± 6.78	16.67 ± 9.32	0.806
Number of glomeruli with global sclerosis	2.55 ± 1.64	3.63 ± 3.89	0.396
Number of glomeruli with segmental sclerosis	2.53 ± 1.64	4.37 ± 3.56	0.057
Tubular atrophy
Mild	5 (100)	4 (66.7)	0.455
Moderate	0 (0)	2 (33.3)
Fibrointimal thickening of arteries
Mild	22 (91.7)	17 (68)	0.074
Moderate	2 (8.3)	8 (32)
Focal segmental glomerulosclerosis variants
Not otherwise specified	15 (51.7)	24 (46.2)	0.012
Tip	11 (37.9)	7 (13.5)
Collapsing	2 (6.9)	15 (28.8)
Hilar	1 (3.4)	0 (0)
Cellular	0 (0)	1 (1.9)
Unknown/unclassified	0 (0)	5 (9.6)

Data are n (%). BP: Blood pressure.

Doubling of serum creatinine was seen in 13/52 (25.0%) steroid non-responsive patients. A total of seven patients developed KFRT, while 15 patients developed CKD. We did not observe any mortality among this cohort of patients.

Table 4 compares the main clinicopathological parameters and outcomes between two groups of adult FSGS patients treated with steroids: (1) Those with kidney function loss (n = 81); and (2) Those with normal kidney function (n = 254) at presentation. Table 4 highlights significant differences between patients with kidney function loss and those with normal kidney function who were treated with steroids. Patients with kidney function loss were older and had higher initial proteinuria, higher serum creatinine levels, more glomeruli with global sclerosis, and a higher rate of moderate tubular atrophy. They also had worse outcomes in terms of the doubling of serum creatinine compared to those with normal kidney function. Other parameters, such as sex, BP, serum albumin, steroid dose, treatment duration, time to remission, and glomeruli with segmental sclerosis, did not show statistically significant differences.

Table 4 Comparison of main clinicopathological parameters and outcomes among the two groups [those with kidney function loss (n = 81) and those with normal kidney function (n = 254) at presentation] of adult focal segmental glomerulosclerosis patients treated with steroids.

Parameters	Kidney function loss, n = 81	Normal kidney function, n = 254	P value
Age in years	36.3 ± 14.7	26.5 ± 10.4	< 0.001
Sex as male:female	2.5:1	1.9:1	0.328
Systolic in mmHg	131.9 ± 19.8	128.4 ± 17.9	1.464
Diastolic in mmHg	86.5 ± 12.8	83.9 ± 12.2	1.664
Serum albumin in g/dL	1.9 ± 1.0	1.9 ± 1.1	0.807
Initial proteinuria in mg/24 hours	5626.2 ± 3787	4396.0 ± 2805.2	0.009
Serum creatinine in mg/dL	2.2 ± 1.3	0.8 ± 0.2	< 0.001
Follow-up duration in weeks	136.8 ± 120.6	152.94 ± 115.6	0.243
Total steroid dose in mg	4391.5 ± 1502.3	4279.6 ± 2039.5	0.649
Duration of steroid treatment in weeks	19.90 ± 14.4	23.27 ± 23.9	0.231
Time to remission	11.3 ± 6.7	12.6 ± 20.4	0.705
Number of glomeruli with global sclerosis	3.6 ± 2.9	2.0 ± 1.5	< 0.001
Number of glomeruli with segmental sclerosis	3.2 ± 3.2	2.9 ± 2.6	0.61
Tubular atrophy
Mild	39 (79.6)	133 (90.5)	0.044
Moderate	10 (20.4)	14 (9.5)
Outcomes
Complete remission	20/81 (24.7)	66/254 (25.9)	0.428
Partial remission	9/81 (11.1)	42/254 (16.5)
No remission	52/81 (64.2)	146/254 (57.4)
Doubling of serum creatinine	13/52 (25.0)	16/146 (10.9)	0.007

Data are n (%).

DISCUSSION

Here, we present our experience in one of the largest case series of primary FSGS, focusing on the clinical course and outcomes of adult patients with FSGS who had a loss of kidney function and an eGFR < 60 mL/minute/1.73 m² upon presentation. The SIUT provides free healthcare services to a significant portion of the Pakistani population, which ensures high compliance and regular follow-up. The racial homogeneity of our study population allows for an accurate estimation of the clinical course and outcomes of the FSGS cohort with kidney function loss at presentation.

Kidney function loss was found in 24.4% (98 patients) of FSGS cases upon arrival, with a male-to-female ratio of 2.5:1. These findings are consistent with previous studies. Hemodynamic alterations in acute-onset NS and chronic irreversible changes may contribute to the low eGFR observed at presentation[8,14,15]. Previous reports suggest that steroids can halt FSGS progression or stabilize eGFR, supporting the former mechanism of action in most patients[8].

Corticosteroids are the mainstay of FSGS treatment, and response to steroids is the best predictor of outcomes[16-19]. In this cohort of 81 patients treated with steroids, 29 (35.8%) were steroid-responsive, while 52 (64.1%) were steroid non-responsive. The overall response rate, including CR and PR, was 35.8%. Response rates to steroids in prior studies have varied from 30% to 67%, depending on the dose and duration of steroid treatment[8,16-19]. These findings highlight the need for more robust and targeted therapeutic strategies to improve the treatment outcomes for patients with primary FSGS.

A lower baseline protein excretion was associated with a favorable response to steroids, although it did not reach statistical significance. Prior studies have noted that patients with heavy proteinuria have more severe disease[20-22]. Conversely, lower protein excretion has not consistently been shown to predict a response to steroids.

Surprisingly, the steroid-responsive group had a higher eGFR at presentation compared to the steroid non-responsive group, which was statistically significant. Elevated serum creatinine and decreased eGFR are generally poor prognostic markers in terms of response to steroids and overall kidney survival. In a study enrolling patients with serum creatinine ≥ 1.4 mg/dL, remission was achieved in only 35.8% of patients, compared to 64.1% in those with lower serum creatinine concentrations[15]. In the steroid-responsive group, there was a statistically significant decrease in serum creatinine and an increase in eGFR, comparable to a prior study conducted at our institute[8].

In patients with FSGS, response to steroids is associated with long-term preservation of renal function[23-25]. Lower levels of serum creatinine showed more complete and partial responses (25.9% and 16.5%) compared to raised levels (24.6% vs 11.1%), with raised creatinine on arrival being associated with KF and the need for kidney replacement therapy on follow-up.

The study has certain limitations related to its retrospective nature, medium-term follow-up duration of 34 months, and being a single-center experience. All eligible patients were treated only with steroids.

CONCLUSION

In conclusion, primary FSGS patients with low eGFR at presentation have better outcomes if they are steroid-responsive. However, the presence of declining kidney function at presentation is an adverse prognostic indicator, with most patients showing no response to treatment and progressing to overt KF.