1. Current Management of Anal Fistulas in Crohn’s Disease
Rita YK Chang
Joint Hospital Surgical Grand Round
23th April 2016

2. Background 20-50% Crohn’s disease (CD) have perianal fistula
More distal luminal CD are at higher risk
90% proctitis have fistula
Low remission and high recurrence
More complications
Stricture, stenosis, abscess

3. Classification Park’s classification High vs. low Simple vs. complex
Secondary branches
Involving >= 1/3 of the sphincter circuit
Anterior fistulas in women
Faecal incontinence, strictures

5. Investigations Colonoscopy Examination under anaesthesia (EUA):
Concomitant active proctocolitis
Malignancy
Examination under anaesthesia (EUA):
Accuracy of 90%
Allow concomitant surgery

6. Investigations Pelvic MRI: Endoanal ultrasound
Non-invasive
Identifying deep abscesses and classifying fistulas, sphincter anatomy
Endoanal ultrasound
3-dimensional
Enhanced with hydrogen peroxide
Requires expertise
Rectal stenosis has to be excluded
Ultrasound or MRI used together with EUA are 100% accurate (Schwartz et al. 2001)

7. Contrast-enhanced fat suppressed T1-weight MRI

9. Management principle
Medications traditionally control intestinal CD are ineffective for perineal CD
Not all surgical treatment for crytograndular perianal fistula are beneficial to Crohn’s perianal fistula
Treat active luminal Crohn’s disease
Drain perianal abscess as urgency
Combined approach: medical + surgical

10. Management outline Medical Surgical: Drainage of abscess
1st line: antibiotics (metronidazole + ciprofloxacin)
Symptoms typically recur immediately after discontinuation
2nd line:  immunomodulators (azathioprine/6-mercaptopurineas)
Slow response (at least 8 weeks)
Leukopenia and drug-induced hepatitis
3rd line: Biological agents: (infliximab/ adalimumab)
Surgical: Drainage of abscess

11. Adalimumab for the treatment of fistulas in patients with Crohn's disease (Colombel et al. 2009)
CHARM = Crohn’s Trial of the Fully Human Antibody Adalimumab for Remission Maintenance
Fistula efficacy defined as no draining fistulas at the last two consecutive period before and on that visit

12. Infliximab maintenance therapy for fistulizing Crohn’s disease (Sands etal. 2004)

13. Medical therapy- anti-TNF
Infliximab (IV)
5–10 mg/kg body weight
Induction: 0, 2, and 6 weeks
Maintenance: every 8 weeks (for 1 year)
Adalimumab (SC)
Induction: 160 mg in 0 week, 80 mg in week 2, 40 mg every other week until week 12
Maintenance: 40 mg every other week (for 1 year)
Efficacy in closing fistula ~50% in 10 weeks

14. Is anti-TNF the ultimate solution?
Adverse reaction
severe septic infections, drug-induced lupus, haemic malignancies
Relapses after discontinuation of therapy
17% at 1 year
40% at 5 years
Cost

15. Surgery principle: more alleviative then radical
Radical treatment not advocated
High rate of recurrence, impaired wound healing, damage to the anal sphincter
I&D, non-cutting seton
timing of seton removal: no consensus

16. Fistula classification Concomitant proctitis Management Simple, low No
Fistulotomy
Sphintcer-preserving procedures (fibrin glue, fistula plug and LIFT)
Yes
Non-cutting seton
Complex, high
Mucosal advancement flap or
Rectal sleeve advancement if anal canal disease
+/- Temporary stoma
Temporary fecal diversion
Proctectomy
Cristina B. Geltzeiler, Nicole Wieghard, Vassiliki L. Tsikitis. Recent developments in the surgical management of perianal fistula for Crohn’s disease. Annals of Gastroenterology (2014) 27,

17. Anorectal advancement flap
Complicated by anal canal ulceration or stricturing
rectal sleeve advancement with temporary fecal diversion
extensive version of the rectal mucosal advancement flap
full thickness of the rectum is circumferentially mobilized after excision of the ulcerated or strictured area
Formal proctoanal anastomosis is performed in combination with diverting loop ileostomy. Although
Occ required trans-abdominal mobilization
Rakinic J, Poola VP.  Curr Probl Surg (3):98-137

18. Anorectal advancement flap
Healing rate: 25-64%
Incontinence rate: 9.4%
Temporary stoma
Mild proctitis
Significant sphincter involvement
History of failed repairs
47% restore intestinal continuity

19. Proctectomy Proctectomy rate 12-38%; higher if proctitis
Often difficult healing of the perineal wound
Myocutaneous flap (rectus abdominus flap/ gracilis flap) may be required

20. New treatment Local anti-TNF injection Stem cell in fibrin glue
Video-assisted fistula treatment

21. Maintenance medical therapy
Fistulotomy
Sphincter-preserving procedures
Healing of fistula
Simple fistula
Look out for malignancy
Treat active luminal Crohn’s disease
Sepsis control:
I&D, seton, antibiotics
Complex case: Stoma
Chronic seton (proctitis)
Mucosal advancement flap (no proctitis)
Proctectomy
Yes No
Refractory, aggressive
Medical therapy
Cristina B. Geltzeiler, Nicole Wieghard, Vassiliki L. Tsikitis. Recent developments in the surgical management of perianal fistula for Crohn’s disease. Annals of Gastroenterology (2014) 27,

22. References:
Cristina B. Geltzeiler, Nicole Wieghard, Vassiliki L. Tsikitis. Recent developments in the surgical management of perianal fistula for Crohn’s disease. Annals of Gastroenterology (2014) 27,
Elsa Limura, Pasquale Giordano. Modern management of anal fistula. World J Gastroenterol 2015 January 7; 21(1): 12-20
Meniero P. Tech Coloproctol :347
Rojanasakul A . LIFT procedure: a simplified technique for fistula-in-ano. TechColoproctol. 2009 Sep;13(3):
Yamaguchi T, Kagawa R, Takahashi H, Takeda R, Sakata S, Nishizaki D. Diagnostic implications of MR imaging for mucinous adenocarcinoma arising from fistula in ano. Tech Coloproctol. 2009 Sep;13(3): doi: /s z. Epub 2009 Jul 17.
Rakinic J, Poola VP. Hemorrhoids and fistulas: new solutions to old problems. Curr Probl Surg (3):98-137
G.A. Santoro, C. Ratto. Accuracy and Reliability of Endoanal Ultrasonography in the Evaluation of Perianal Abscesses and Fistula-in-ano. P
Z Abdool, A H Sultan,  R Thakar. Ultrasound imaging of the anal sphincter complex: a review. Br J Radiol Jul; 85(1015): 865–875
Michael R. Torkzad and Urban Karlbom. MRI for assessment of anal fistula. Insights Imaging May; 1(2): 62–71