Table 4. Proposed cut-off values for determination of the major amyloid subclasses.
| Protein | Corresponding subgroup (pmol/mm3) |
Other subgroups (pmol/mm3) |
Cut-off value | ||
|---|---|---|---|---|---|
| Mean ± SD | Range min-max | Mean ± SD | Max (#sample) | ||
| SAA | AA subgroup (n = 14/7 cases) | n = 34 | max+6SD | ||
| 134.976 ± 80.031 | 38.054–268.439 | 1.188 ± 2.466 | 11.484 (#21–2) | 26.280 | |
| TTR | ATTR subgroup (n = 14/7case) | n = 34 | max+6SD | ||
| 216.195 ± 85.117 | 56.514–367.852 | 0.538 ± 0.898 | 3.499 (#27–2) | 8.887 | |
| IGK | ALk subgroup (n = 8/4cases) | n = 40 | mean+2SD | ||
| 71.898 ± 38.314 | 14.751–128.572 | 4.214 ± 4.371 | 26.404 (#7–1) | 12.956 | |
| IGL | ALl subgroup (n = 10/5cases) | n = 38 | mean+2SD | ||
| 33.771 ± 13.212 | 19.037–60.228 | 2.912 ± 2.694 | 16.742 (#7–1) | 8.300 | |
| B2M | AB2M subgroup (n = 2) | n = 46 | max+6SD | ||
| - | 55.141–77.763 | 0.641 ± 0.303 | 1.837 (#25–2) | 3.655 | |
Analysis was performed using the data of immunohistochemically determined subgroups (each corresponding amyloid subgroup vs. other subgroups)
B2M, beta-2-microglobulin; IGK, immunoglobulin kappa light chain; IGL, immunoglobulin lambda light chain; SAA, serum amyloid A; TTR, transthyretin