| Antibody isotype | n | Percentage (%) |
| Total antibodies | 5 | 2.7 |
| IgA | 1 | 0.5 |
| IgG | 22 | |
| IgM | 24 | 12.8 |
| IgA/IgM | 2 | 1.1 |
| IgM/IgG | 112 | 59.6 |
| IgA/IgG/IgM | 2 | 1.1 |
| N/R | 20 | 10.6 |
| Total | 188 | 100 |