Table 1 Demographic data of all patients

Age, years

27.5 ± 10.2

28.7 ± 10.9

25.8 ± 9.0

Sex

 Male

110

64

46

 Female

26

13

13

Symptoms (n)

 Asymptomatic

88 (64.7)

59 (76.6)

29 (49.2)

 Symptomatic

48 (35.3)

18 (23.4)

30 (50.8)

  Pain

16

6

10

  Discharge

10

6

4

  Pain + discharge

22

6

16

Previous perianal surgery (n, %)

47 (34.6)

28 (36.4)

19 (32.2)

Time from the first surgery to diagnosis, months

n = 47

n = 28

n = 19

 Median (IQR)

24 (5, 36)

24 (6.25, 48)

12 (4, 36)

Montreal classification (n)

Age

 A1

15

7

8

 A2

105

59

46

 A3

16

11

5

Location

 L1

29

17

12

 L1 + 4

2

1

1

 L2

34

16

18

 L2 + 4

2

–

2

 L3

57

36

21

 L3 + 4

12

7

5

Behavior

 B1

100

55

45

 B2

21

9

12

 B3

13

11

2

 B2 + 3

2

2

–

C-reaction protein, mg/L

37.06 ± 33.75 (n = 131)

30.81 ± 30.12 (n = 75)

45.43 ± 36.70 (n = 56)

ESR, mm/h

28.55 ± 21.09 (n = 130)

24.08 ± 18.73 (n = 75)

34.64 ± 22.73 (n = 55)

PDAI (mean ± SD)

3.83 ± 3.41

2.7 ± 1.8

5.3 ± 4.4