TABLE 1. The basic clinical features.
| Item | n (%) | |
| Gender | male | 107 (77.0) |
| female | 32 (23.0) | |
| CD course | <1year | 79 (56.8) |
| 1~10year | 54 (38.8) | |
| >10 year | 6 (4.3) | |
| Anal fistula course | <1 year | 74 (53.2) |
| 1~10 year | 60 (44.6) | |
| >10 year | 5 (3.6) | |
| Relationship between the two courses | Anal fistula appears first Simultaneously CD diagnosed first | 66 (47.5%) 27 (19.4%) 46 (33.1%) |
| Number of previous abdominal surgeries | 1 | 23 (16.5) |
| >1 | 4 (2.9) | |
| Perianal surgeries history | Anal fistula surgery | 38 (27.3) |
| Perianal abscess surgery | 56 (40.3) | |
| Hemorrhoids surgery | 6 (4.3) | |
| Anal fissure surgery | 2 (1.4) | |
| Else♦ | 1 (0.7) | |
| Number of previous perianal surgeries | 1 | 58 (41.7) |
| >1 | 32 (23.0) | |
| Medication history | Yes 5-ASA | 103 (74.1) 62 (44.6) |
| SASP | 15 (10.8) | |
| Immunosuppressor | 24 (17.3) | |
| Corticosteroid | 31 (22.3) | |
| Biologics | 22 (15.8) | |
| Antibiotic | 16 (11.5) | |
| Enteral nutrition | 28 (20.1) | |
| Else* | 23 (16.5) |
♦ =resection of perianal mass; * =treatment of Chinese herbal pieces, extract of Chinese herbal pieces, transplantation of fecal bacteria, anti-tuberculosis, antiviral treatment and so on.