Intermittent high-volume hemofiltration promotes remission in steroid-resistant idiopathic nephrotic syndrome

Figures & data

Figure 1. Flowchart of patient selection. INS, idiopathic nephrotic syndrome; SS, steroid-sensitive group; SR, steroid-resistant group; SRD, steroid resistance with drugs group; SRDF, steroid resistance with drugs and hemofiltration group; GC, glucocorticoid; MMF, mycophenolate mofetil; IHVHF, intermittent, high-volume hemofiltration.

Table 1. Baseline clinical characteristics of the SRD- and SRDF-group patients.

	SRD (n = 35)	SRDF (n = 16)	p for trend
Gender (M/F)	20/15	9/7	0.33
Age (years)	48.9 ± 16.6	55.3 ± 13.2	0.53
Proteinuria (g/24 h)	6.9 ± 4.7	7.9 ± 4.4	0.65
Serum albumin (g/l)	23.5 ± 3.6	21.6 ± 3.2	0.28
Serum creatinine (μmol/l)	67.8 ± 15.1	106.2 ± 31.4	< 0.001
eGFR (mL/min/1.73 m^2)	80.69 ± 11.4	64.7 ± 11.5	< 0.001
Urinary output (l/d)	1.61 (1.23–2.04)	0.62 (0.31–0.82)	< 0.001
Edema	Mild	Severe
Hear failure/Ascites	None	Common
BNP (pg/Ml)	289 (106–1240)	2876 (1547–4214)	<0.001
Fibrinogen (mg/dl)	4.5 ± 1.2	4.4 ± 0.9	0.33
Cholesterol (μmol/l)	342.9 ± 92.5	363.4 ± 91.9	0.69
Low-density lipoprotein (μmol/l)	187.9 ± 59.3	216.3 ± 50.9	0.31
High-density lipoprotein (μmol/l)	89.7 ± 27.4	104.8 ± 40.1	0.25
Triglycerides (μmol/l)	241.2 ± 111.3	217.1 ± 108.7	0.56
Pathological types
MCD	5 (14.3%)	3 (18.75%)	0.61
MN	20 (57.2%)	8 (50%)	0.25
FSGS	6 (17.1%)	3 (18.75%)	0.45
MPGN	4 (11.4%)	2 (12.5%)	0.15

Notes: Values are expressed as mean and standard deviation or medians and interquartile ranges or number and percentage. p Values were calculated using an independent t-test in the case of the former and the Mann--Whitney U test in the case of the two latter.

eGFR, estimated glomerular filtration rate (estimated using the Modification of Diet in Renal Disease equation modified for the Chinese population); BNP, B-type natriuretic peptide; MCD, minimal change disease; MN, membranous nephropathy; FSGS, focal segmental glomerulosclerosis; MPGN, mesangialproliferative glomerulonephritis.

Figure 2. Renal function and proteinuria remission during follow-up in patients in the steroid resistance with drugs (SRD) and steroid resistance with drugs and hemofiltration (SRDF) groups. (A) Cumulative complete remission. (B) Time to complete remission. (C) Complete remission at specific time points. (D) Serum creatinine. (E) Estimated glomerular filtration rate (eGFR). (F) Serum albumin. (G) Levels of 24 h urine protein excretion. (H) Proteinuria reduction in patients entering a complete remission. p Values are for SRD vs. SRDF, *p < 0.01.

Figure 3. Influence of intermittent, high-volume hemofiltration (IHVHF) on serum cytokine levels in the patients in the steroid resistance with drugs and hemofiltration (SRDF) group. IL, interleukin.

Table 2. Cytokine clearance (Cl) with intermittent, high-volume hemofiltration (IHVHF).

Cl (mL/min)	2 h	4 h	6 h	8 h	p for trend
IL-8	20.56 (17.58–22.88)	26.49 (22.35–29.25)	19.86 (15.39–22.10)	19.85 (14.79–22.35)	0.03
IL-10	18.41 (13.85–22.35)	10.80 (10.43–17.26)	9.14 (8.45–16.37)	9.58 (8.03–15.43)	0.04
IL-6	16.24 (11.89–19.38)	16.59 (12.49–19.56)	15.28 (10.33–18.42)	16.54 (12.03–19.31)	0.81
IL-17	8.63 (5.84–10.73)	9.00 (6.30–10.69)	8.92 (5.89–11.67)	8.33 (5.41–9.89)	0.79

Notes: Values are expressed as medians and interquartile ranges. p Values were calculated using the Kruskal–Wallis H test.

Table 3. Serum cytokine levels in controls and patients with idiopathic nephrotic syndrome (INS) at disease onset.

Level (pg/mL)	Control	SS	SRD	SRDF	p for trend
IL-8	50.08 (31.52–92.54)	97.45 (64.91-133.8)	178.3 (89.2–258.0)	297.16 (200.89–362.75)	<0.001 * <0.01
IL-10	61.8 (42.31–90.24)	105.8 (87.28–147.35)	90.19 (64.07–145.32)	155.5 (82.93–245.38)	0.03
IL-6	47.71 (32.15–121.4)	150.35 (82.93–245.38)	144.22 (98.33–239.42)	145.5 (83.75–235.41)	0.04
IL-17	30.12 (21.54–42.31)	31.05 (20.51- 55.32)	37.94 (15.89–54.67)	28.35 (16.49–35.76)	0.15

Notes: Values are expressed as medians and interquartile ranges. p Values were calculated using the Kruskal–Wallis H test.

*for SRD vs. SRDF.

Figure 4. Relationship of serum interleukin (IL) levels with disease activity and sensitivity to glucocorticoids in patients with idiopathic nephrotic syndrome (INS). (A) Serum cytokine levels and INS activity. (B) Area under the receiver operating characteristic curve (AUC) suggests that serum IL-8 level at INS onset is a predictor of sensitivity to glucocorticoids.