Table 1.
Characterization of patients at baseline (i.e. the day of rituximab injection) and during follow-up.
| Variables | All patients (n = 68) | Patients with serum rituximab level < 2µg/mL at month-3 (n = 38) | Patients with serum rituximab level > 2µg/mL at month-3 (n = 30) | P-value |
|---|---|---|---|---|
| Characteristics at baseline | ||||
| Age (years) | 58.5 [49.0–67.2] | 57.5 [44.0–67.5] | 60.5 [50.5–68.0] | 0.3 |
| Gender (Female/Male) | 19/49 | 14/24 | 5/25 | 0.1 |
| Weight (kg) | 76.6 [67.4-84.0] | 76.3 [66.6-83.6] | 77.0 [67.9-86.0] | 1 |
| UP (g/d) | 6.0 [4.3–8.9] | 7.0 [4.9–10.1] | 5.5 [3.9–7.1] | 0.07 |
| Serum creatinine (µmol/L) | 120 [87–151] | 119 [83–138] | 137 [90–183] | 0.1 |
| Serum albumin (g/L) | 22.6 [16.0–29.0] | 20.2 [14.1–24.6] | 26.6 [22.0–31.7] | 0.001 |
| CD19+ count (cell/µL) | 186.5 [123.5–270.0] | 208.0 [138.0–280.0] | 142.5 [77.2–215.5] | 0.2 |
| Etiology | 0.2 | |||
| Anti-PLA2R1-associated pMN | 62 (91%) | 35 (92%) | 27 (90%) | |
| Anti-THSD7A-associated pMN | 2 (3%) | 0 (0%) | 2 (7%) | |
| Double negative patients | 4 (6%) | 3 (8%) | 1 (3%) | |
| Anti-PLA2R1 Ab titer (RU/mL) | 149 [57–303] | 184 [71–489] | 89 [20–173] | 0.01 |
| Anti-proteinuric treatment | 68 (100%) | 38 (100%) | 30 (100%) | 1 |
| Characteristics at month-3 | ||||
| UP (g/d) | 3.0 [1.5–5.9] | 5.4 [2.4–8.1] | 1.8 [1.1–3.2] | <0.0001 |
| Serum creatinine (µmol/L) | 110 [92–142] | 110 [87–139] | 105 [92–166] | 0.7 |
| Serum albumin (g/L) | 29.0 [23.0–35.0] | 24.6 [17.7–31.3] | 35.0 [29.5–37.3] | 0.0002 |
| CD19+ count (cell/µL) | 2.0 [0.0–7.0] | 2.5 [0.9–18.5] | 0.0 [0.0–2.0] | 0.005 |
| Anti-PLA2R1 Ab titer (RU/mL) | 5 [0–23] | 19 [5–63] | 0 [0–4] | <0.0001 |
| Patients with anti-RTX Ab | 0 (0%) | 0 (0%) | 0 (0%) | 1 |
| Characteristics at month-6 | ||||
| UP (g/d) | 1.7 [1.0–4.7] | 4.5 [1.7–8.0] | 1.2 [0.6–1.7] | <0.0001 |
| Serum creatinine (µmol/L) | 107 [89–137] | 110 [90–139] | 104 [85–142] | 0.7 |
| Serum albumin (g/L) | 32.5 [25.5–37.0] | 29.0 [22.2–33.6] | 37.0 [32.8–39.2] | <0.0001 |
| CD19+ count (cell/µL) | 22.5 [3.0–52.2] | 41.0 [19.0–127.0] | 2.0 [1.0–33.0] | 0.0009 |
| Anti-PLA2R1 Ab titer (RU/mL) | 3 [0–24] | 15 [2–80] | 0 [0–4] | <0.0001 |
| Patients with anti-RTX Ab | 6 (9%) | 4 (11%) | 2 (7%) | 0.7 |
| Clinical outcome | ||||
| Remission at month-6 | 36 (53%) | 12 (32%) | 24 (80%) | <0.0001 |
| Remission at month-12 | 41 (60%) | 16 (42%) | 25 (83%) | 0.001 |
Anti-PLA2R1 Ab, anti-Phospholipase A2 Receptor 1 antibody; Anti-THSD7A Ab, anti-Thrombospondin Type 1 Domain Containing 7A antibody; Anti-RTX Ab, anti-rituximab antibody; pMN, primary membranous nephropathy; UP, 24-hour urinary protein excretion.