Table 1.
Features of different subtypes of MG
| Early-onset MG (EOMG) | Late-onset MG (LOMG) | Thymoma-associated MG (TAMG) | Anti-MuSK-Ab-associated MG (MAMG) | Ocular MG (OMG) | “Seronegative”MG (SNMG) | |
|---|---|---|---|---|---|---|
| Estimated frequency | 20 % | 45 % | 10–15 % | 6 % | 15 % | 4 % |
| Disease-course and manifestation | Generalized, disease maximum within the first 3 years | Generalized, disease maximum within the first 3 years | Generalized, more scarcely—complete remission is possible | Generalized, fasciopharyngeal focus | Ocular | Generalized |
| Age at disease onset | ≤45 (50, 60) yearsa | >45 (50, 60) yearsa | Any age (primarily 40–60 years) |
Any age (primarily Younger patients) |
Any age | Any age |
| Male: female ratio | 1:3 | 5:1 | 1:1 | 1:3 | 1:2 | n. a. |
| HLA-association (caucasians) | B8 A1 DR3 (strong) DR16 DR9 (less strong) | B7 DR2 (less strong) Anti-titin-ab− with DR7 Anti-titin-ab+ with DR3 |
DR7 (less strong) A25 (less strong) |
DR14 (strong) | n. a. | n. a. |
| (Auto-)antibodies | Anti-AChR-ab |
Anti-AChR-ab
Anti-Titin-ab Anti-RyR-ab Anti-IL12-ab Anti-IFNα-ab |
Anti-AChR-ab
Anti-Titin-ab Anti-RyR-ab Anti-IL12-ab Anti-IFNα-ab Anti-IFNω-ab |
Anti-MuSK-ab |
Anti-AChR-ab
(50–70 %) |
Anti-LRP4-ab
Anti-Argin-ab |
| Typical thymus pathology | lymphofollicular hyperplasia (LFH) | Atrophy, involution | Thymoma Type A 5 % Type AB, B1–3 92 % |
Usually normal | No systematic data | No systemic data |
| Response to thymectomy | good when performed within the first 1–2 years after diagnosis | No systematic data | Often poor | Poor | No systematic data | No systematic data |
| Response to immunotherapy | +++ | +++ | +(+) | +(+) | +++ | +(+) |