TABLE 5.
Relating histologic rejection diagnoses to Expert1MMDx rejection sign-out comments (6 classes, N = 1679)
| Histologic diagnoses (6 classes) | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rejection-related, N = 740 | No rejection | No rejection excluding PVNa | Row totals | No. discrepancies per row (%) | ||||||||
| AMR-related, N = 417 | Mixed, N = 56 | TCMR-related, N = 267 | ||||||||||
| AMR | pAMR | TCMR | pTCMR (borderline) | |||||||||
| AMR suspicious | CG | |||||||||||
| Expert1MMDx sign-out comments (6 class) |
AMR-related,N = 561 | AMR | 260 | 17 b | 32 b | 25 c | 20 d | 24 d | 131 d | (127) | 509 | 249/509 (49%) |
| Possible AMR | 12 b | 1 | 1 | 1 c | 3 d | 5d | 29 b | (26) | 52 | 50/52 (96%) | ||
| Mixed | 6 c | 2 c | 1 c | 22 | 25 c | 4 c | 9 c | (8) | 69 | 47/69 (68%) | ||
| TCMR-related,N = 144 | TCMR | 5 d | 0 | 1 d | 5 c | 55 | 9 b | 48 d | (22) | 123 | 68/123 (55%) | |
| Possible TCMR | 0 | 0 | 0 | 1 c | 8 b | 3 | 9 b | (6) | 21 | 18/21 (86%) | ||
| No rejection | 50 d | 13 b | 16 b | 2 c | 28 d | 83 b | 713 | (698) | 905 | 192/905 (21%) | ||
| Column totals | 333 | 33 | 51 | 56 | 139 | 128 | 939 | (887) | 1679 | 624/1679 (37%) | ||
| No. discrepancies per column (%) | 73/333 (22%) | 32/33 (97%) | 50/51 (98%) | 34/56 (61%) | 84/139 (60%) | 125/128 (98%) | 226/939 (26%) | 189/887 (21%) | 624/1679 (37%) | |||
pTCMR and pAMR were ignored in definite AMR or TCMR respectively. Twenty-six Expert1MMDx TCMR/Histology NR were PVN virus positive.
Bolding indicates clear rejection/no rejection categories.
Excludes PVN from row totals. Histology usually does not diagnose TCMR in biopsies with PVN; MMDx recognizes molecular TCMR regardless of PVN status, but acknowledges that it does not distinguish whether the TCMR activity is directed against alloantigens, PVN antigens, or both.
Boundary discrepancies between Expert1MMDx and histology (N = 228).
Mixed discrepancies between Expert1MMDx and histology (N = 81).
Clear discrepancies between Expert1MMDx and histology (N = 315).
AMR, antibody-mediated rejection; cg, transplant glomerulopathy; MMDx, Molecular Microscope Diagnostic System; PVN, polyoma virus nephropathy; TCMR, T cell–mediated rejection; TG, transplant glomerulopathy.