Fistula-in-ano different methods of management .ppt

Different methods of management of anal fistula and a new way of controlling post operative pain by using pack containing tannic acid powder and lignocaine cream

1. FISTULA IN-ANU
HAMED RASHAD
Professor of surgery Banha
faculty of medicine -Egypt

2. Anorectal anatomy
Rectum develops from hind gut at 6 weeks
Anal canal formed at 8 weeks –ectoderm.
Dentate line transition from endo to ecto.
Rectum has inner –circular.
outer –longitudinal.
Anal canal –4cm, pelvic diaphragm to
anal verge.

3. Anatomy
External Sphincter-
-U shaped , continuation of levator ani
-deep segment is continuous with puborectalis
muscle and forms anorectal ring felt on DRE.
-striated muscle
-voluntary control
-3 components -sub mucous, superficial and
deep.

4. Anatomy-
Internal sphincter-
-smooth muscle
-autonomic control
-extension of circular
muscles of rectum.
-contracted at rest.

5. Anatomy
4-8 anal glands drained
by respective crypts, at
dentate line.
Gland body lies in
intersphincteric plane.
Anal gland function is
lubrication.
Columns of Morgagni
8-14 long mucosal fold.

6. Anorectal anatomy

7. Ano-rectal sepsis
Sx: perineal pain (throbbing), possible prior history of similar
Exam:tender fluctuant mass +/-discharge, may be toxic
Beware:diabetics (risk of rapidly progressive infection &
skin necrosis (possible Fournier’s gangrene)
anal spasm & throbbing pain (inter-sphincteric abscess)
Treatment: I&D

8. Pathophysiology
Infection starts in crypto glandular epithelium
lining the anal canal.
Internal anal sphincter a barrier to infection
passing from gut to deep perirectal tissue.
Duct of Anal gland penetrate internal sphincter
into intersphincteric space.
Once infection sets in intersphincteric space it
can spread further.

9. Anorectal sepsis

10. Perianal abscess
acute infection originating in anal gland


11. Natural history of perianal abscess
Drainage via anal gland
resolution
Drainage via abnormal
route
Resolution of abscess
Creation of fistula
Intersphincteric
Trans-sphincteric
others

12. Anorectal Sepsis
Treatment
Adequate incision and drainage
Elliptical, saucerisation
Drains usually not necessary, packing counterproductive
Drains encircling horseshoe abscess
Seton if fistula can be identified
•Often difficult in presence of inflammation/infection
Antibiotics/immune suppression
Supralevator: MRI/CT to determine source of sepsis

13. Drainage of Perianal Abscess
50% of abscesses will develop fistulae
Perirectal drainage when feasible
Avoids creation of Fistula to perianal skin

14. Anorectal Fistula
(Fistula-in-Ano)
“Chronic form” of anorectal
abscesses
Connection/tract between
two epithelial-line structures
Internal opening-Anal crypt of the
gland
External opening-
Perianal/Perineal skin
Other: rectovesicular, rectovaginal, rectourethral
fistula

15. Pathogenesis of Fistulae
Pentrating ulcers
extend with time
Anal gland infection
tracks along
intersphincteric space

16. Pathophysiology
Anal gland infection
Perianal abscessDrainage self/ surgery
Fistula formation

17. Frequency
Common in 3
rd
and 4
th
decade of life
Male > female (2:1)
30% present with previous episodes.
Increase incidence during summer and
spring.
Common in infants , poorly understood
mechanism , fairly benign and majority
settle with simple drainage.

18. Etiology
Abscess initially forms in the
intersphincteric space and spreads along
adjacent potential spaces.
Common organisms-
* E.Coli
* Enterococcus species
* Bacteroides species.

19. Etiology
Less common causes -
Crohn’s Disease.
Cancer.
Tuberculosis.
Trauma.
Leukemia.
Lymphoma.

20. Fistula
Most fistulas begin as an anorectal
abscess
Anal fistulas is an abnormal passage or
communication between the interior of the
anal canal or rectum and the skin surface
Rarer forms may communicate with the
vagina, large bowel, and bladder

21. Fistula in ano
~ 30-40% of all perineal sepsis once drained goes on to develop
a fistula
~ 80-90% of perineal sepsis that yielded enteric organisms will
develop a fistula

22. Fistula in ano
95% cryptoglandular
-ie origin in ano-rectal crypts at dentate line
5% rarities
-Crohn’s
-TB
-hidradenitis suppurativa
-traumatic
-malignancy
-complicated diverticular disease
-radiation
-anastomotic leakage

23. Classification
Inter-sphincteric 70%
Trans-sphincteric 25%
Supra-sphincteric ~5%
Extra-sphincteric <1%
Simple v. complex
‘Complex’:
-branching tracts / 2y tracts
-associated abscess
-associated pathology

24. Park’s Classification of Anorectal
Fistulas
Type 1 –
Intersphincteric, most
common
Type 2 –Transphincteric
Type 3 –
Suprasphincteric
Type 4 -Extrasphincteric

25. Park’s Classification of Anorectal
Fistulas

26. Fistula-in-ano
A. Intersphincteric-
Via internal sphincter
to intersphincteric
space then to
perineum.
70%
B. Transsphincteric-
Via internal and
external sphincter into
Ischiorectal fossa and
then to perineum.
25%

27. Fistula-in-ano
C. Suprasphincteric–
Via intersphincteric
space superiorly to
above puborectalis
muscle into
Ischiorectal fossa
then perineum.
5%
D. Extrasphincteric-
From Perianal skin
through levator ani
muscles to the rectal
wall completely
outside sphincter
mechanism.
<1%

28. Classification
Type I –Intersphincteric (70%)
Type II-Transsphincteric (23%)
Type III-Suprsphincteric (5%)
Type IV-Extrasphincteric (2%)

29. Park’s Classification
Superficial
Intershincteric
Transphincteric
Suprasphincteric
Extrasphincteric

30. Park Classification system-
A.Intersphincteric
B.Transsphincteric
C.Suprasphincteric
D.Extrasphincteric

31. Goodsall’s rule
External opening posterior to 3-9
oclock position open in posterior
midline of the anal canal
External opening anterior to 3-9 oclock
position open radially in the anal canal
~80-90% accurate

32. Fistula

33. Simple Fistula

34. Complex
Horse shoe fistula

35. Complex Fistula
Crohn’s

36. Complex Fistula
Malignancy

37. Complex Fistula
Malignancy

38. Complex Fistula
Anterior Type Females

39. Crohn’s Fistula

40. Simple vs. Complex Fistula
Simple
Superficial, intersphincteric,
low transsphincteric
single opening
does not involve another organ
Complex
supra-, extra-, trans-sphincteric
multiple openings
involves bladder or vagina

41. Simple Fistula

42. Complex Fistula

43. Clinical Presentation
Abscess: Pain,swelling,fever
Perianal: Tender anal verge, fluctuanat mass,erythema
Ischiorectal: Larger, less dramatic cutaneous findings
Intersphincteric/supralevator: Severe rectal pain
Perianal soilage or bleeding
UTI or Vaginal Drainage
Evaluation
Often difficult beside
EUA
Black spot –widespread necrotising infection

44. Clinical presentation
History–Recurrent Swelling, Discharge,
Pain and Surgery for an Abscess.
Symptoms–
-Perianal discharge -Pain
-Swelling -Bleeding
-External opening

45. Anorectal Fistula
Clinical Presentation
Hx
Chronic drainage from
“nonhealing abscess”
Pain with defecation
Pruritus
Physical exam
Draining pustule
Erythema, induration,
excoriated skin
DRE-firm cord (fistula
tract)

46. Clinical presentation
Past medical history-
* Inflammatory bowel disease.
* Diverticulitis
* Previous pelvic radiation
* Tuberculosis
* Steroids therapy
* HIV infection

47. Fistula-Symptoms
Are usually a purulent discharge and
drainage of pus or stool near the anus
Can irritate the outer tissues causing
itching and discomfort
Pain occurs when fistulas become blocked
and abscesses recur
Flatus may also escape from the tract

48. Clinical presentations
Physical examination-
* Look at entire perineum,
* An open sinus or elevation of granulation
tissue.
* Discharge may be seen.
* DRE-fibrous cord, or cord beneath the skin.
* Voluntary squeeze pressures & sphincter tone
should be assessed.

49. Fistula
Fistulas can be difficult to diagnosis
A probe must be passed between the
opening of the skin’s surface and the
interior opening
Goodsall’s Rulecan be helpful
Other causes include tuberculosis,
inflammatory bowel disease, and cancer

50. Diagnostic testing
MRI –
facilitates identification of tracts
EUS (endorectal ultrasond)
visualize air in tracts
CT
evaluate for undrained abscess
Fistulography
EUA (ex under anaethesia)
utilized for patients requiring surgical intervention
diagnostic and therapeutic

51. Imaging Studies
Not indicated for routine evaluation
Performed when external opening is difficult to
identify, recurrent or multiple fistulae.
1.Fistulography-
-involves injection of contrast via the opening
and taking images in different planes.
-15-48% accuracy.

52. Fistulography
Fistulography involves cannulation of the external
opening with injection of water soluble contrast
It may be useful for evaluation of recurrent or
complex fistulae.
Its use has been generally discouraged
because of risk of septicemia in a small amount
of patients and poor visualization of anatomic
landmarks.
This study has been substituted by other
diagnostic modalities

53. Imaging studies
2. Endo Anorectal Ultrasonography -
-Transducer 7-10 MHz.
-Installation of H2O2 can help location of
internal opening .
-not widely used.
3. MRI-
-Study of choice
-80-90% concordance with oper.finding.
-good for primary course and sec extensions.

54. Imaging
4. CT Scan–
-Good for perirectal inflammation disease,
delineating fluid pockets.
-Needs oral and rectal contrast.
-poor delineation of muscular anatomy.
5. Barium enema / Small bowel series-
-Useful in multiple fistulae or recurrent
disease, also to rule out IBD.

55. fistula imaging
MRI showing
intersphincteric fistula
anteriorly
Prm-puborectalis
muscle.

56. Fistulography

58. Fistulography

59. Fistulography

60. Posterior and lateral fistulae

61. Horse shoe fistula with long blind
track

63. Direct posterior fistula

64. The
xeroradiography

65. Other investigations
Anal Manometry-
Pressure evaluation of sphincter mechanism
help in some cases -
-Decreased tone in preop evaluation
-previous fistulectomy
-obstetrical trauma
-high transsphincteric or suprasphincteric fistula
-very elderly patient.
If decreased, avoid -surgical division of any
portion of sphincter.

66. Diagnostic procedures
A. E U A-
Examination of perineum, DRE, anoscopy.
To look for internal opening techniques-
-Inject -H2O2, Milk, Dilute methylene blue
-Traction on external opening may help
-Probing gently can help.
B. Proctosigmodoscopy / Colonoscopy-
Rigid sigmoidoscopy to rule rectal disease.

67. Goodsall’s Rule
Transverse Line
Straight tracks
Radial opening
Curved tracks
Opening post midline
>3 cm
Goodsall’s rule often does not apply in Crohn’s Disease

68. Management of fistula in ano
Strike a balance between
-cure of fistula
-prevention of further anorectal abscess
-preservation of continence

69. Exam Under Anesthesia
Goal is to identify the external, internal
openings, the course of the tract,
presence of secondary connections,
presence of other rectal disease.

70. Exam Under Anesthesia
Scope placed in such a way as to view the
known or predicted location of the internal
opening. A curved probe is gently introduced
and guided to the internal opening. Occasionally
you can pass it the other way.
Can place small catheter into external opening
and flush with methelyne blue, peroxide, sterile
milk, or air. Identification successful in 86%.

71. Anorectal Fistula
Treatment
Aim: eliminate fistula, prevent recurrence, preserve sphincter
Identification of primary opening and limiting muscle division
Intersphincteric / transphincteric: Laying open
Proximal to dentate line: seton
Extrasphincteric: Lower portion divided, rectal opening closed.
May need temporary colostomy
Fibrin Glue? Long, narrow but enthusiasm fading
Plug
Diversion
Proctectomy

72. Exam under Anesthesia (EUA)

73. EUA
Explore and identify all tracts
Hydrogen Peroxide and methylene blue
to faciliate identification of primary opening
Determination of relationship to sphincter
Avoid creating new tracts

74. Causes of failure
• Failure to appreciate anatomy of tract(s)
• Failure to control the primary tract
• Overlooked secondary sepsis / tracts
• Iatrogenic tracts
• Unusual pathology

75. Surgical Treatment of Anal Fistula
Fistulotomy
Setons
Advancement flaps*
Other techniques
Fibrin glue*
Fistulotomy & immediate reconstruction of the
divided musculature, with 1
0
wound closure*.
Fistulectomy
Defunctioning colostomy
*Need to eradicate acute sepsis before more
complex procedures undertaken for anal fistula

76. Management
1. Fistulotomy / Fistulectomy -
-laying open technique is useful in 85-95% of
primary fistulae.
-overlying skin, subcutaneous tissue, internal
sphincter divided with electrocautry, curette
tract to remove granulation tissue.
-complete fistulectomy creates bigger wound
with no advantage in minimizing recurrence.
-perform biopsy of firm or suggestive tissue.

77. Management
2. Seton Placement–
-Alone, in combination with fistulectomy or as a
stage procedure-
Useful in –
Complex fistulae
Recurrent fistulae after fistulectomy
Anterior fistulae in females
Poor preop sphincter pressure.
Immunosuppresed patients.

78. Fistulotomy

79. Anorectal Fistulas
Management of Simple Fistulas
Fistulotomy

80. Management of Simple fistula

81. Management of Simple fistula

83. Fistulotomy : Metheline blue injected in the
external opening

84. Proctoscopy : The dye comes from the
internal opening

86. Fistulotomy : Aprope is iserted in the track

87. Fist is begun : the dye shows the track

89. Wound edges are excized

91. Wound sauserized : Fistulotomy completed

93. Anterior and posterior separate
fistulae

94. Begining the
fistulotomy

95. Completing the anterior fistulotomy

96. Inserting seton

99. Anterior and
posterior fistulae
with two setons

100. Tannic acid powder is
used to cover the raw
area( It is an astringent
destroys nerve endings,
causing haemostasis and
lessen secondary infcetion )

102. Lignocain cream
is mixed with
tannic acid to form a
paste and put into a
piece of gause and
packed in the rectum
and raw area

103. Anterior fistula –Ext opening in the scrotum
and internal opening at 3 O’clock position

105. Anal fistula : Goodsall’s role

106. Methyline blue

107. Probe inserted

108. Internal opening in midline posteriorly

109. Final shape of posterior fistula

110. Probe entered the
internal opening
with remaining
part of anal
sphincter…..
Seton ??

112. Remember to
destroy the anal
gland with
diathermy

113. Two stage technique long anterior
fistula (sphincter is weaker specially in females)

114. Fistula Management
Management depends on the anatomy of the
fistula. If it is apparent that the fistula is simple,
and low, and the location of the internal opening
can be inferred by probing, fistulotomy can be
performed over the probe thru the predicted site
of the internal opening at the dentate line.
The entire tract is opened along its length. This
should be reserved for low intersphinteric
fistulae, which are short, posterior, and in which
the external sphincter is not involved.

115. Lay open VsPlug

116. Fistula Management
Fistulotomy should be avoided anteriorly,
especially in women.
Anal fistulae that involve a large portion of
the external sphincter are considered
complex, as are multiple fistulae, IBD
patients, impaired preoperative
continence. These may require use of a
seton.

117. Setons
Definition: from Latin word seta, meaning bristle.
First used around 600 BC in India.
Materials used for setons include:
Types of setons:
Drainage / Loose
Cutting / Tight
Chemical
Silicone rubber Polyester
Silk Wire
Nylon Herbal medicated threads
Rubber Horse hair

118. Seton placement-
Seton defines sphincter muscles
Promotes -Drainage
-Fibrosis.
Material used-
-Silk suture
-Silastic vessel markers
-Rubber bands

119. Setons
Potential actions of the seton
Act as a drain for acute sepsis
To allow resolution of inflammation prior to definitive fistula
surgery
Role in staged fistulotomy
Delineation of the amount of muscle caudal to the fistulous
track
Cutting & Chemical setons:
Controlled division of the enclosed sphincter mechanism
with minimal separation of the transected ends.

120. Seton
Authors Types of fistulae
treated
Seton method/No. of
Patients
Healing
Rates
Altered Continence
Kennedy &
Zegarra
1990
High
transsphincteric &
suprasphincteric
Loose silk
32
25/32 (78%)9/25
Parks & Stitz
1976
High fistulae Loose
68
? 17% seton + distal fistulotomy (to
dentate line)
39% above + division of seton
contained muscle
Thomson &
Ross
1989
Complex idiopathic
transsphincteric
Loose
34
44% without
division of
EAS
17% altered continence in the
‘cured’ group
68% altered continence in group
requiring division of EAS
Goldberg
1996
TranssphinctericCutting
13
100% 7/13 minor incontinence
1/13 major incontinence
Deshpande
& Sharma
1973
All types Chemical
200
93%
7% 2
nd
appln
?
Shulka et al
1991
High & low Chemical
RCT 502
96% 4%

121. Seton Fistulotomy
Fistulotomy is accomplished gradually. The
muscle contained in the seton is slowly divided
due to pressure necrosis, with the divided ends
separating only minimally because of the fibrosis
that develops behind the seton.
An elastic seton (vessel loop) is drawn thru the
tract a loosely secured to itself, tighten
sequentially over time. Repeat every two weeks
until division of the muscle is complete.

122. Laser
The main options are ligation of the fistula tract, closure using a clip or
filling the fistula by injecting biological infill agents;[2] however, the
success rate of these techniques in treating FIA is only in the region of
50%.[2,3] The main cause of this low success rate is the inability of these
methods to disrupt the epithelial integrity of the fistula tract. As the fistula
epithelium preserves its integrity with conventional sphincter-sparing
methods, success rates are low and recurrence rates are high[4] For this
reason, an alternative method that would be able to destroy the epithelial
integrity of the fistula tract, while protecting the patient from sepsis and
preserving the sphincters was needed, and in response to these
requirements, laser ablation therapy was developed.[5] This technique uses
laser energy: A radial laser probe sent into the fistula tract destroys the
epithelium of the fistula tract with its 360-degree laser energy and also
causes shrinkage. In this way, it serves to close the fistula.[5]

123. Laser
All patients were treated under spinal anesthesia in the
lithotomy position. After identifying the external and internal
openings, the fistula tract was cleaned with a curette and
irrigated with saline. First, the inner opening of the fistula was
closed using 3/0 absorbable surgical suture (MITSU™ Meril
Endo Surgery Pvt. Ltd.). Then, a 10 W 1470 nm radial laser
probe (G.N.S neoLaser Ltd.© HaEshel, Israel) was advanced
along the fistula tract and then withdrawn slowly, delivering
360°laser energy for 3 s per 1 cm. In this way, the fistula tract
was completely obliterated. If there were no complications,
patients were discharged after overnight observation. Oral pain
medication was started 6–8 h after the spinal anesthesia and no
dietary restrictions were imposed.

124. Results
In this study, we found an acceptable primary success rate
(77.5%) and a high secondary success rate (95%) for the laser
ablation method. With a success rate comparable to other
methods, the biggest advantage of laser ablation therapy seen
in our study was the lack of major perioperative complications
in any of the patients.

125. Complex Fistula
*Cutting Seton (Staged Fistulotomy)*-
tightening of seton at regular intervals allows for slow
transection of muscle, minimizing sphincter dysfunction
Recurrence= 0-18%
Incontinence rate= 0-30%
Mucosal advancement flap-mobilize flap that
covers the internal fistulous opening
Indication= recurrent fistula
Recurrence= 0-36%
Incontinence rate= 0-13%
Anorectal Fistulas
Management

126. •Cutting seton(staged fistulotomy)
–Thread silk suture through fistula tract, tie
together on outside
–Incise SKIN ONLY over fistula tract
–Tighten setonat regular intervals, slowly
cutting through sphincter
–Gradual cutting causes muscle scarring
leaving muscle ends near usual location after
being transected, thus minimizing disruption of
sphincter and decreasing risk of incontinence
Anorectal Fistulas
Management of Complex Fistulas

127. Anorectal Fistulas
Management of Complex Fistulas
Cutting Seton (Staged Fistulotomy)

128. Surgical Options –Cutting Seton
Lay open external tract
Draining seton replaced
with cutting seton
1/0 Prolene suture
Tied tight around
sphincter complex
Simultaneous slow cutting
and repair of sphincter
May require re-tightening

129. Seton

130. Complex Fistula
LIFT Procedure

131. Horse shoe fistula ? best way

132. Drainage seton
Infant feeding tube
Vascular sling

133. Follow up
Sitz bath
Analgesia
Stool bulk agents (bran)
Frequent office visits to ensure healing.
Healing in 6 weeks.

134. Complications
Early-
Urinary retention
Bleeding
Fecal impaction
Thrombosed
hemorrhoids.
Delayed-
Recurrence
Incontinence stool)
Anal stenosis
Delayed wound
healing.

135. Outcome & Prognosis
Following Rate of
Recurrence
Incontinence of
stool
Standard
Fistulotomy
0 -18% 3 -7 %
Seton 0 –17% 0 -17 %
Mucosal
advancement
flap
1-10% 6 –8%

136. Rectal Advancement Flaps

137. 3.Mucosal Advancement Flap -
In chronic high fistula , indication same as seton.
Total fistulectomy , removal of primary and
secondary tract with internal opening
Rectal mucomuscular flap is raised .
Internal muscle defect is closed with absorbable
suture and flap is sewn down over internal
opening.
Single stage procedure
Poor success in Acute infection and Crohn’s.

138. Mucosal advancement flap
Anorectal Fistulas
Management of Complex Fistulas

139. Endorectal Flap Advancement
High recurrence rate
57% in patients with Crohns Disease
Wexner et al. Dis Colon Rectum 2002
100 % in patients with Crohn’s
Hyman et al. Am J Surg 1999

140. Fibrin Glue
Benefits:
Sphincter apparatus not disturbed
No significant scarring from the treatment
Technique
EUA; identification of primary and any
secondary tract openings.
Fistula tract then curetted
Fibrin adhesive injected into the secondary
tract opening until seen coming from the
primary opening.
Vaseline gauze applied over the openings

141. Anorectal Fistulas
Management of Simple Fistulas
Anal Plug

143. Fibrin Glue
Thrombin & Fibrinogen
2-chamber syringe
Mix at delivery
Cannula tip up to internal
opening and withdrawn while
injecting
Early results: promising
Follow up: disappointing
Against conv seton-RCT
Lindsey et al:DCR2002;45:1608-15
Advocated
Zmora et al:DCR 2003;46(5):584-589
With antibiotics-RCT
Singer M et al: DCR 2005; 48:799-808
Advancement Flap and Glue
–RCT
Paul J van et al:Int J Colorectal Ds
2008;23:697-701
Cochrane Systematic Review
Associated with worse outcome
Gone with the wind

144. Fibrin Glue
Anorectal Fistulas
Management of Simple Fistulas

145. Fibrin Glue
Study Results:
Lindsay I; Dis Colon & Rectum 2001
55% healed at in the short term (8/12 follow up)
Probably little advantage over conventional Rx but
may be useful first line treatment for higher fistulas
Cintron JR; Dis Colon & Rectum Jul 2000
54% fistula closure at 12 months with autologous
fibrin
64% fistula closure at 12 months with commercial
fibrin sealant.
Most treatment failures occurred within 3 months

146. Fibrin Glue
Fibrin glue alone
33% healing rate at 12 months
Fibrin glue at time of advancement flap
54% healing rate at 12 months
Wexner et al. Dis Colon Rectum 2003

147. Anal Fistula Plug

148. Anal Fistula Plug ( AFP )
Johnson et al, 2006; DCR 49(3):371-376
-New biological material
-Absorbable
-Lyophilized porcine intestinal submucosa
Champagne BJ et al, 2006; DCR 49(12):1817-1821
Success rate 83% at 12 months

149. Plugging

153. Fistula Plug

154. Fistula Plug scheme of technique

157. Failed anal fistula plug
High Cost : May not be the best

158. Anal Fistula Plug
Prospective trial 25 patients with complex
fistulae
13% recurrence rate with plug
60% recurrence with fibrin glue
Johnson et al. Dis Colon Rectum 2006

159. Anal Fistula Plug
AFP and Crohns Disease
8 patient successfully treated
No Long term studies

160. Fecal Diversion
May be performed
laparoscopically
Prevents fecal drainage
Often performed in
conjunction with
seton/med mgmt.
REVERSIBLE
Fistula may re-open

161. Proctectomy
Invasive
Permanent Stoma
Wound complications
Stoma complications
DEFINITIVE

162. Summary
Fistula in Ano complex problem
Requires multidisciplinary approach
Surgery reserved for those cases refractory
to initial medical therapy
Stepwise progression beginning with least
invasive operative procedures.

163. Treatment Algorithm
Simple fistula Complex Fistula
Antibiotics/immune therapy Surgical evaluation
antibiotics/immune meds
Failure Success Failure Success
Treat as complex Maintenance meds Remedial surgeryMaintain meds
Tacrolimus

164. THANK YOU
GOOD LUCK