Fistula In Ano - Standard Treatment Guidelines

When a patient presents with a discharging opening gin the perianal region, one should suspect a fistula in ano

Ministry of Health and Family Welfare, Government of India has issued the Standard Treatment Guidelines for Fistula In Ano. Following are the major recommendations :

A fistula is an abnormal communication between two epithelial surfaces.

Definition :

By definition a fistula in ano is a communication between the anal canal and skin by a tract which may be straight and simple or complex with ramifications or a horse shoe tract involving the right and / or left halves. The discharge may be pus, fecal matter, flatus or serosanguinous.

Fistula are classified as low or high

Based upon their relationship to the anal sphincter complex, anal fistulas are categorized into:

1. Intersphincteric

2. Trans sphincteric

3. Supra sphincteric

4. Extra sphincteric

Treatment options are based upon these classifications

Incidence : Indian incidence is not documented

Differential Diagnosis

Furunculosis

Crohn’s disease

Pilonidal sinus

Tuberculosis

Actimycosis

Lymphogranuloma venereum

Granuloma inguinale

Perianal abcess

Prevention

Adequate drainage of anorectal abscesses may prevent fistula formation

Predisposing causes

1. Crohn’s disease

2. Malignancy

3. Chlamydia

In the presence of a complex, recurrent, non healing fistula these should be suspected.

Counselling

Surgical treatment alone offers permanent cure. So patients should be counseled for early surgey when it is a simple fistula so that it does not become complex.

Optimal Diagnostic Criteria :

Situation 1

Clinical Diagnosis

Patients with anal fistula commonly present with complaints of

• Discharge from external or internal opening, the external opening may be single or multiple


• Pain


• Swelling


• Fever

The presentation may be acute when there is acute perianal sepsis

A chronic anal fistula presents with periodic exacerbation and pus discharging openings around the anus per rectal exam and proctoscopy should be done to visualize both the internal and external openings. This may be adequate for a straight low tract.

Investigations:

Fistulogram may be done when branching is suspected, in recurrent fistulae and when internal opening is not appreciable.

Examination under anesthesia

Probe test, caution may cause now internal opening

Injection technique is useful in delineating the tract

Biopsy when specific cause is anticipated

Barium enema – when co existing disease is suspected

Blood sugar – to r/o diabetes mellitus

Complete blood count

Urine r/m

X ray chest – to rule out TB

Treatment:

Simple low fistulae can be managed in a secondary hospital where a surgeon is available

Surgical Procedures :

Surgical options are dictated by the type of fistula. Aim is to drain the septic focus and remove the fistula with minimal injury to the sphincter complex

Fistulotomy

Fistulectomy

Seton

Combination of the above:

Fistulotomy (of superficial position), with seton division (of the cephalad position)

Staged procedures may be required in high anal fistulae

Fistula presenting as perianal abscess would require drainage, analgesics and antibiotics followed subsequently by a definitive procedure

Fistulotomy and curettage / Fistulectomy – low anal fistula

Trans sphincteric fistula that involve =<30 percent of sphincteric muscle – sphincteromy without risk of incontinence

High Trans sphincteric fistulas – seton placement

Referral criteria:

Complex/recurrent/high anal fistulae may need referral to a higher centre for adequate investigation and management. Colostomy and staged procedure may be required.

Co existing conditions like rectal cancers, Crohn’s disease, TB fistulae, HIV infection require referral

SOP:

In patient

SITUATION 2:

Clinical Diagnosis

Patients with anal fistula commonly present with complaints of

• Discharge from external or internal opening, the external opening may be single or multiple


• Pain


• Swelling


• Fever

The presentation may be acute when there is acute perianal sepsis

A chronic anal fistula presents with periodic exacerbation and pus discharging openings around the anus per rectal exam and proctoscopy should be done to visualize both the internal and external openings. This may be adequate for a straight low tract.

Investigations:

Fistulogram may be done when branching is suspected, in recurrent fistulae and when internal opening is not appreciable.

Examination under anesthesia

Probe test, caution may cause now internal opening

Injection technique is useful in delineating the tract

Biopsy when specific cause is anticipated

Barium enema – when co existing disease is suspected

Blood sugar – to r/o diabetes mellitus

Complete blood count

Urine r/m

X ray chest – to rule out TB

Additional investigations:

MRI, MR Fistulogram in complex, high, trans sphincteric, supra and extrasphincteric fistulae

Colonoscopy – associated ulcerative colitis, carcinoma, TB etc

HIV test in suspected cases

Biopsy when multiple openings are present, malignancy or specific cause is suspected prothrombin time

HbA1C in cases of diabetes mellitus

Treatment:

Simple low fistulae can be managed in a secondary hospital where a surgeon is available

Surgical Procedures :

Surgical options are dictated by the type of fistula. Aim is to drain the septic focus and remove the fistula with minimal injury to the sphincter complex

Fistulotomy

Fistulectomy

Seton

Combination of the above:

Fistulotomy (of superficial position), with seton division (of the cephalad position)

Staged procedures may be required in high anal fistulae

Fistula presenting as perianal abscess would require drainage, analgesics and antibiotics followed subsequently by a definitive procedure

Fistulotomy and curettage / Fistulectomy – low anal fistula

Trans sphincteric fistula that involve =<30 percent of sphincteric muscle – sphincteromy without risk of incontinence

High Trans sphincteric fistulas – seton placement

Colostomy – when significant sphincter involvement is present, or non healing ulcer Multiple procedures – complex fistula with multiple tracts

SOP:

Day Care – Low fistulae – subcutaneous / submucous fistula

All others – should be admitted

WHO DOES WHAT?

Doctor

Clinical examination

Diagnosis

Planning surgery

Post op care

Anesthesia

Nurse

Siting of colostomy when required, by stoma nurse

Care of stoma

Dressing of the wound

Pre & post operative care

Assisting during surgery

Technician

Pre op equipment and drugs to be checked and kept ready

Assist anesthetist in the OT

Assist the surgeon, positioning of the patient

Resources Required For One Patient / Procedure (Patient weight 60 Kgs)

Guidelines by The Ministry of Health and Family Welfare :

Dr Ajit Sinha Department of Surgery Safdarjung Hospital New Delhi