Table 2.
Characteristics of patients and treatment at the start of apheresis
| Total population |
Remission |
No remission |
P value | |
|---|---|---|---|---|
| n = 21 | n = 7 | n = 14 | ||
| Clinical and biological characteristics | ||||
| Age (y) [IQR] | 34 [24–50] | 51 [31–65] | 30 [22–40] | 0.05 |
| Min-Max (years) | 16–76 | 16–76 | 16–49 | |
| Hemoglobin level (g/dl) [IQR]; n = 18/21, 6/7, 12/14 | 10.9 [9.2–12.3] | 9.6 [9.1–11.7] | 11.3 [10.1–12.8] | 0.17 |
| Platelet count (109/l) [IQR]; n = 17/21, 6/7, 11/14 | 299 [249–365] | 294 [235–333] | 319 [228–377] | 0.59 |
| Absolute neutrophil count (109/l) [IQR]; n = 16/21, 6/7, 10/14 | 6.1 [4.4–7.7] | 4.6 [2.2–6.7] | 6.4 [5.4–8.5] | 0.14 |
| Renal parameters | ||||
| Systolic blood pressure (mm Hg) [IQR]; n = 18/21, 5/7, 13/14 | 137 [120–146] | 130 [109–141] | 140 [120–146] | 0.27 |
| Diastolic blood pressure (mm Hg) [IQR]; n = 18/21, 5/7, 13/14 | 80 [70–90] | 78 [55–83] | 80 [70–92] | 0.32 |
| Serum albumin concentration (g/l) [IQR] | 17.0 [11.4–22.9] | 20.0 [11.2–28.0] | 16.6 [11.4–20.9] | 0.5 |
| Proteinuria (g/d) [IQR] | 5.3 [4.0–10.5] | 3.9 [3.0–5.1] | 7.3 [4.9–11.0] | 0.03 |
| Absolute change in proteinuria (g/d) [IQR] | −2.9 [−5.4; 2.0] | −5.5 [−14.0; −2.9] | 0.5 [−4.5; 3.6] | 0.03 |
| Absolute monthly change in proteinuria (g/d/mo) [IQR] | 0.0 [−0.6–0.1] | −0.6 [−2.9; −0.3] | 0.0 [−0.2; 0.2] | 0.008 |
| Serum creatinine concentration (μmol/l) [IQR]; n = 18/21, 4/7, 14/14 | 142.5 [110.0–198.5] | 153.5 [112.2–207.5] | 142.5 [103.2–185.5] | 0.87 |
| eGFR (ml/min per 1.73 m2) [IQR]a | 48.0 [25.0–66.5] | 28.0 [0–52.0] | 48.5 [39.8–75.0] | 0.05 |
| CKD stage | ||||
| - I (%) | 2 (9.5) | 0 | 2 (14.3) | 0.79 |
| - II (%) | 3 (14.3) | 0 | 3 (21.4) | 0.51 |
| - III (%) | 10 (47.6) | 3 (42.9) | 7 (50.0) | 1 |
| - IV (%) | 2 (9.5) | 1 (14.3) | 1 (7.1) | 1 |
| - V (%) | 4 (19.1) | 3 (42.9) | 1 (7.1) | 0.17 |
| Time from diagnosis to apheresis (mo) [IQR] | 10 [5–25] | 8 [1–11] | 19 [7–26] | 0.17 |
| Absolute change in eGFR (ml/min per 1.73 m2) [IQR] | −29.0 [−54.3; −6.9] | −28.0 [−83.0; −7.0] | −29.0 [−51.2; −4.7] | 0.68 |
| Absolute monthly change in eGFR (ml/min per 1.73 m2/mo) [IQR] | −2.9 [−6.2; −0.3] | −6.8 [−12.6; −3.1] | −1.5 [−3.4; −0.2] | 0.04 |
| Dialysis before apheresis /at the last follow-up | ||||
| - no/no (%) | 13 (61.9) | 4 (57.1) | 9 (64.3) | } 0.01 |
| - yes/no (%) | 3 (14.3) | 3 (42.9) | 0 | |
| - no/yes (%) | 5 (23.8) | 0 | 5 (35.7) | |
| Specific treatments for INS before apheresis | ||||
| Number of immunosuppressive drugs with corticosteroids | ||||
| - 1 immunosuppressive drug (%) | 10 (47.6) | 7 (100.0) | 3 (20.0) | 0.003 |
| - ≥ 2 immunosuppressive drugs (%) | 11 (52.4) | 0 | 11 (78.6) | 0.003 |
| Number of treatments without corticosteroids [IQR] | 2 [1–3] | 1 | 2 [1–3] | 0.002 |
| Min - Max | 1; 6 | 1 | 1; 6 | |
| Duration of corticosteroid use before apheresis - median [IQR] (month) | 7.0 [5.0–24.0] | 5.0 [1.0–7.0] | 15.0 [6.0–25.2] | 0.05 |
| Immunosuppressive therapy used before apheresis | ||||
| - Calcineurin inhibitor (%) | 13 (61.9) | 4 (57.1) | 9 (64.3) | 1 |
| Cyclosporine (%) | 13 (61.9) | 4 (57.1) | 9 (64.3) | |
| Tacrolimus (%) | 8 (38.1) | 0 | 8 (57.1) | |
| - Cyclophosphamide (%) | 4 (19.1) | 2 (28.6) | 2 (14.3) | 0.84 |
| - Rituximab (%) | 8 (38.1) | 1 (14.3) | 7 (50.0) | 0.27 |
| - Mycophenolate mofetil (%) | 7 (33.3) | 0 | 7 (50.0) | 0.07 |
| - Intravenous immunoglobulin (%) | 1 (4.8) | 0 | 1 (7.1) | 1 |
| Mode of apheresis | ||||
| Type of apheresis | ||||
| - Plasma exchange (%) | 11 (52.4) | 6 (85.7) | 5 (35.7) | 0.09 |
| - Immunoadsorption (%) | 6 (28.6) | 0 | 6 (42.9) | 0.12 |
| - Double-filtration plasmapheresis (%) | 2 (9.5) | 1 (14.3) | 1 (7.1) | 1 |
| - Plasma exchange followed by immunoadsorption (%) | 1 (4.8) | 0 | 1 (7.1) | 1 |
| - Low-density lipoprotein apheresis (%) | 1 (4.8) | 0 | 1 (7.1) | 1 |
| Number of apheresis sessions [IQR] | 12 [4–39] | 11 [4–74] | 12 [7–32] | 0.97 |
| - ≤ 3 (%) | 3 (14.3) | 1 (14.3) | 2 (14.3) | |
| - [4–15](%) | 10 (47.6) | 3 (42.9) | 7 (50) | |
| - ≥ 15 (%) | 8 (38.1) | 3 (42.9) | 5 (35.7) | |
| Duration of apheresis (days) [IQR] | 47 [17–172] | 56 [13–1954] | 40 [21–114] | 0.56 |
| Min-Max | 6; 2296 | 7; 2296 | 6; 338 | |
| Specific treatments for INS after apheresis | ||||
| Dose of corticosteroids at the start of apheresis (mg/d) [IQR] | 15 [1–60] | 30 [7–65] | 10 [0–60] | 0.36 |
| Immunosuppressive therapy used after and during apheresis | ||||
| - Calcineurin inhibitor (%) | 12 (57.1) | 5 (71.5) | 7 (50.0) | 0.64 |
| Cyclosporine (%) | 7 (33.3) | 5 (71.5) | 2 (14.3) | |
| Tacrolimus (%) | 7 (33.3) | 0 | 7 (50.0) | |
| - Cyclophosphamide (%) | 2 (9.5) | 2 (28.6) | 0 | 0.19 |
| - Rituximab (%) | 3 (14.3) | 2 (28.6) | 1 (7.1) | 0.51 |
| - Mycophenolate mofetil (%) | 4 (19.1) | 0 | 4 (28.6) | 0.36 |
| - Intravenous immunoglobulin (%) | 2 (9.5) | 0 | 2 (14.3) | 0.79 |
| - Azathioprine (%) | 2 (9.5) | 1 (14.3) | 1 (7.1) | 1 |
| - Ofatumumab (%) | 1 (4.8) | 0 | 1 (7.1) | 1 |
Qualitative data are expressed as n (%), quantitative data as medians [interquartile range; IQR], as appropriate.
Glomerular filtration rate (GFR) was estimated (eGFR) by the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation.
CDK stage was defined according to National Kidney Foundation practice guidelines for CKD.
a
eGFR = 0 ml/min per 1.73 m2 for the 3 patients on dialysis.