Table 4.
Baseline characteristics of aABMR, aTCMR, and NR patients.
| Variable | aABMR* n = 17 | aTCMR* n = 18 | NR n = 15 | p |
|---|---|---|---|---|
| Recipient | ||||
| Age at time of transplantation in (yr, mean ± SD) | 43,9 ± 13,9 | 47,5 ± 17,7 | 49,9 ± 15,6 | 0,47 |
| Type of transplantation | 0,04 | |||
| Living Related (n, %) | 3 (17,6) | 3 (16,7) | 6 (40) | |
| Living Unrelated (n, %) | 7 (41,2) | 2 (11,1) | 5 (33,3) | |
| Donation after Brain Death (n, %) | 6 (35,5) | 9 (50) | 3 (20) | |
| Donation after Cardiac Death (n, %) | 1 (5,9) | 4 (22,2) | 1 (6,7) | |
| Gender (n, %) | 0,07 | |||
| Female sex | 4 (23,5) | 11 (61,1) | 5 (33,3) | |
| Primary renal disease (n, %) | 0,73 | |||
| Diabetic nephropathy | 0 (0) | 2 (11,1) | 0 (0) | |
| IgA nephropathy | 4 (23,5) | 1 (5,6) | 5 (33,3) | |
| Glomerulonephritis | 0 (0) | 2 (11,1) | 0 (0) | |
| Polycystic kidney disease | 3 (17,6) | 5 (27,8) | 1 (6,7) | |
| Pyelonephritis | 0 (0) | 0 (0) | 0 (0) | |
| Hypertensive nephropathy | 3 (17,6) | 3 (16,7) | 1 (6,7) | |
| MPO-vasculitis | 0 (0) | 0 (0) | 2 (13,3) | |
| Unknown | 2 (11,8) | 0 (0) | 3 (20) | |
| Other | 5 (29,4) | 5 (27,8) | 3 (20) | |
| Donor | ||||
| Gender (n, %) | 0,68 | |||
| Female sex | 6 (35,3) | 7 (38,9) | 8 (53,3) | |
| missing | 4 (23,5) | 1 (5,6) | 1 (6,7) | |
| Age at time of donation (yr, median ± IQR) | 47 ± 20 | 54 ± 13) | 54,5 ± 20 | 0,09 |
| Transplant and Transplantation characteristics | ||||
| HLA mismatches (n, %) | ||||
| mismatches of HLA-AB | 0,13 | |||
| 0 | 0 (0) | 4 (22,2) | 1 (6,7) | |
| 1 | 2 (11,8) | 4 (21,1) | 2 (13,3) | |
| 2 | 9 (52,9) | 6 (33,3) | 7 (46,7) | |
| 3 | 4 (23,5) | 2 (11,1) | 2 (13,3) | |
| 4 | 1 (5,9) | 1 (5,6) | 1 (6,7) | |
| missing | 1 (5,9) | 1 (5,6) | 2 (13,3) | |
| mismatches of HLA- DR | 0,32 | |||
| 0 | 4 (23,5) | 6 (33,3) | 3 (20) | |
| 1 | 7 (41,2) | 10 (55,6) | 6 (40) | |
| 2 | 4 (23,5) | 1 (5,6) | 4 (26,7) | |
| missing | 2 (11,8) | 1 (5,6) | 2 (13,3) | |
| CMV serological status (n, %) | 0,08 | |||
| Donor-/recipient- | 7 (41,2) | 1 (5,6) | 2 (13,3) | |
| Donor+/recipient- | 5 (29,2) | 6 (33,3) | 4 (26,7) | |
| Donor-/recipient+ | 1 (5,9) | 5 (27,3) | 3 (20) | |
| Donor+/recipient+ | 4 (23,5) | 6 (33,3) | 6 (40) | |
| Biopsy | ||||
| Time since transplantation (yr, mean ± std) | 4,4 ± 3,4 | 1 ± 1,4 | 0,8 ± 0,3 | <0,01 |
| Age at biopsy (yr, mean ± SD) | 46,8 ± 12,5 | 48,1 ± 16,8 | 51,1 ± 15,3 | 0,71 |
| Rationale for undergoing biopsy (n, %) | <0,01 | |||
| Delayed graft function | 1 (5,9) | 4 (22,2) | 0 (0) | |
| elevated creatinine level | 4 (23,5) | 4 (22,2) | 0 (0) | |
| proteinuria (n, %) | 8 (47,1) | 1 (5,6) | 0 (0) | |
| elevated creatinine and proteinuria | 0 (0) | 3 (16,7) | 0 (0) | |
| cyst formation | 0 (0) | 1 (5,6) | 0 (0) | |
| BK viremia | 0 (0) | 1 (5,6) | 0 (0) | |
| transplantectomy | 2 (11,8) | 0 (0) | 0 (0) | |
| general kidney function decline | 2 (11,8) | 4 (22,2) | 0 (0) | |
| protocol | 0 (0) | 0 (0) | 15 (100) | |
| C4d in biopsy (n, %) | <0,01 | |||
| positive | 16 (94,1) | 1 (5,6) | 0 (0) | |
| negative | 1 (5,9) | 17 (94,4) | 15 (100) | |
| SV40 in biopsy (n, %) | 0,32 | |||
| positive | 0 (0) | 1 (5,6) | 1 (6,7) | |
| negative | 15 (88,2) | 17 (94,4) | 13 (86,7) | |
| missing | 2 (11,8) | 0 (0) | 1 (6,7) | |
| Laboratory measurements | ||||
| LsdL class I (n, %) | <0,01 | |||
| positive | 11 (64,7) | 1 (5,6) | 0 (0) | |
| negative | 6 (35,5) | 13 (72,2) | 3 (20) | |
| missing | 0 (0) | 4 (22,2) | 12 (80) | |
| LsdL class II positive (n, %) | <0,01 | |||
| positive | 14 (82,4) | 3 (16,7) | 0 (0) | |
| negative | 3 (17,6) | 11 (61,1) | 3 (20) | |
| missing | 0 (0) | 4 (22,2) | 12 (80) | |
| LsdL class I and I (n, %) | <0,01 | |||
| LsdL class I and II both negative | 1 (5,9) | 11 (61,1) | 3 (20) | |
| At least one of LsdL class I or class II positive | 16 (94,1) | 3 (16,7) | 0 (0) | |
| missing | 0 (0) | 4 (22,2) | 12 (80) | |
| eGFR (ml/min/1.73m, median ± IQR) | 26 ± 19 | 17,5 ± 12,1 | 49 ± 18 | <0,01 |
| Creatinine Clearance (ml/min, median ± IQR) | 34 ± 37 | 23 ± 15 | 70 ± 21 | <0,01 |
| Protein in 24-hour Urine Samples (g/24 h, median ± IQR) | 1,5 ± 1,9 | 0,3 ± 1,0 | 0,2 ± 0,1 | <0,01 |
| Proteinuria (>0.5g/24h, n, %) | <0,01 | |||
| yes | 13 (76,5) | 7 (38,9) | 0 (0) | |
| no | 1 (5,9) | 10 (55,6) | 12 (80) | |
| missing | 3 (17,6) | 1 (5,6) | 3 (20) |
Categorical and dichotomous variables are presented as absolute numbers and respective percentages. Continuous, non-parametric variables are presented as median and with interquartile range. Continuous, parametric data is provided as mean and standard deviation. Categorical data, as well as parametric continuous variables, are compared between groups by ANOVA, continuous non-parametric by Kruskal-Wallis test. Statistical significance is defined as P < 0.05 (bold). aABMR, active antibody-mediated rejection; aTCMR, acute T-cell mediated rejection; NR, non-rejection; yrs, years; aHUS, atypical hemolytic syndrome; MPO, Myeloperoxidase; IQR, interquartile range; HLA, human leukocyte antigen; CMV, Cytomegalovirus; SV40, simian virus 40; IFTA, Interstitial Fibrosis and Tubular Atrophy; n.a., not applicable; LsdL, Life screen de Luxe; LSA, Lifecodes Single Antigen; DSA, donor-specific antibodies; eGFR, Estimated Glomerular Filtration Rate. *According to Banff’19.