Examination of the fistula

1. EXAMINATION OF SINUS,
FISTULA, FISSURES, ANAL
ABSCESS, HAEMARRHOIDS
AND CLINICAL APPROACH TO
RECTAL PATHOLOGIES
By Takudzwa. Craig. Muchedzi
MbChB September 2019
Texila American University

2. PREPARATION
Position of the patient
 Ensure adequate privacy and uncover the patient from the waist to the
middle of the thigh
 The patient should lie in the left lateral position with the neck and
shoulders rounded so that the chin rests on the chest, hips flexed to 90°
or more, but knees flexed to slightly less than 90°. If the knees are
flexed more than 90°, the patient’s ankles will get in your way.
 f the patient is lying on a soft bed, ask them to move towards you so
that their buttocks are up to the edge of the bed. This makes inspection
easier and tips the abdominal contents forwards, which helps the
bimanual examination.

3. EQUIPMENT
 You need a plastic glove, some inert lubricating jelly and a good light.
 Tell the patient what you are going to do. Explain that you are going to
examine the ‘back passage’ and the inside of the abdomen. Say that it
will be uncom- fortable but not painful, and ask the patient to relax by
breathing deeply and letting their knees go loose.

4. INSPECTION
Lift up the uppermost buttock with your left hand so that you can see the
anus, peri-anal skin and peri- neum clearly. Look for:
 skin rashes and excoriation,
 faecal soiling, blood or mucus,
 scarring, or the opening of a fistula,
 lumps and bumps (e.g. polyps, papillomata,
 condylomata, a peri-anal haematoma, prolapsed
 piles, or even a carcinoma),
 ulcers, especially fissures

5. PALPATION
 Before carrying out a digital examination, particularly if there is a history
of pain on defaecation, place your fingers on either side of the anus
and gently stretch the anal orifice.
 This is to see if there is any spasm associated with a fissure, which may
be visible. If there is spasm or a fissure, in no circumstances carry out
any instrumentation as this could cause severe pain.
 Place the pulp of your gloved right index finger on the centre of the
anus, with the finger parallel to the skin of the perineum and in the
mid-line
 Then press gently into the anal canal, but at the same time press
backwards against the skin of the posterior wall of the anal canal and
the underlying sling of the puborectalis muscle.
 This overcomes most of the tone in the anal sphincter and allows the
finger to straighten and slip into the rectum. Never thrust the tip of
your finger straight in.
 Look at your finger, when you remove it from the rectum, to note
the colour of the faeces and the presence of blood or mucus

6. THE ANAL CANAL
 As the finger goes through the anal canal, note the tone of the
sphincter, any pain or tenderness and any thickening or masses.
 Patients with fissures or abscesses may have so much spasm that rectal
examination is extremely painful. In these circumstances, gently try to
insert your finger, and if there is any reaction from thepatient, abandon
the procedure. A general anaes- thetic may be needed for adequate
assessment


7. THE RECTUM
 Feel all around the rectum as high as possible
 You may have to push quite hard in a fat patient, and in some it is
difficult to feel much beyond the anal canal.
 Note the texture of the wall of the rectum and the presence of any
masses or ulcers. If you feel a mass, try to decide if it is within or
outside the wall of the rectum by testing the mobility of the mucosa
over it. This is a most important distinction.
 Do not forget to feel the lower rectum, just above the anal canal.
Posteriorly, the rectum turns away at a right-angle, and it is easy to miss
a small swelling in this area (and also at sigmoidoscopy).
 Note the contents of the rectum. The rectum may be full of faeces (hard
or soft), empty and col- lapsed, or empty but ‘ballooned out’. Faeces
may feel like a tumour but are indentable, the only rectal mass that is.
 If you can just detect a possible abnormality at your fingertip, ask the
patient to strain or push down. This will often move the mass down 1 or
2 cm or so and bring it within your reach.

8. THE RECTOVESICO POUCH
 Turn your finger round so that the pulp feels for- wards and can detect
any masses outside the rectum in the peritoneal pouch between the
rectum and the bladder or uterus.
 It takes practice to be able to tell the normal prostate and cervix from
an abnormal mass. Do not be downhearted if you get it wrong at first:
experience and confidence are needed.

9. HAEMARRHOIDS
INTRODUCTION
 Also known as Piles
 Anal canal contains cushions, which close it and help to provide an efficient
gas and fluid proof seal. When they enlarge they can either prolapse, be
damaged, bleed and even become pendunculated.
 If condition becomes chronic the prolapse stretches the peri anal skin
below it, so that the haemarrhoid is asscociated with external. skin tag

10. Types
 Internal- above the dentate (pectineal) line, covered with mucous
membrane
 External- below the dentate (pectineal) line, covered with skin
 Interno-external- together occur

11. Classification
Hemorrhoids can be classified according:
 Location
 Severity

12. ACCORDING TO LOCATION
 Primary hemorrhoids: Located at 3, 7, 11 o’clock positions related to the
branches of the superior hemorrhoidal vessels which divides on the
right side into 2, and on the left side it continues as 1.
 Secondary hemorrhoids: One which occur between the primary sites.

13. ACCORDING TO SEVERITY
 First degree: piles within that may bleed but does not come out
 Second degree: piles that prolapse during defecation but returns back
spontaneously
 Third degree: piles prolapsed during defecation, can be replaced back
only by manual help
 Fourth degree: pile that are permanently prolapsed. Piles begin as
pedicle and it is located at the origin of the internal pile i.e. at the level
of anorectum.

14. ETIOLOGY
 Hereditary
 Idiopathic
 Morphologic: weight of the blood column without valves causes high pressure.
 Veins in the lower rectum are in loose submucosal plane but the veins above enter the
muscular layer, which on contraction increases the venous congestion below (more
prevalent in patients with constipation). Superior rectal veins have no valves (as they are
tributaries of portal vein) and so more congestion.
 Other causes:
 Straining, diarrhea, constipation, hard stool, low fiber diet, over-purgation
 Carcinoma rectum, portal hypertension (rare cause)
 Pregnancy: during pregnancy raised progesterone relaxes the venous wall and reduces its tone,
enlarged uterus compresses the pelvic vein and constipation is a common problem.

15. CLINICAL FEATURES
 It occurs at any age but mostly between 30 to 65 years.
 Incidence is equal in both sexes.
 Painless Bleeding- 1st symptom- ‘splash in the pan’- ‘bright red and fresh’-
occurs during defecation
 Note: mucus or fecal soiling may occur, though in general changes in
bowel habit are uncommon and should alert to other cause
 Mass per anum
 Discharge- a mucoid discharge
 Pruritus
 Pain- may be due to prolapse, infection or spasm
 Prolapse of internal hemorrhoids may produce moisture in the anal region
or mucus discharge that causing itching.
 Anemia- secondary

16. EXAMINATION
 On inspection, prolapsed piles will be visualized
 On P/R examination, only thrombosed piles can be felt.

17. DIFFERENTIAL DIAGNOSES
 Carcinoma
 Rectal prolapse
 Perianal warts
 Causes of bleeding per anum
  Piles
 Fissure in ano
 Fistula in ano
 Polyps
 Ulcerative colitis
 Amoebic colitis
 Carcinoma rectum and carcinoma colon
  Diverticulitis
 Intussusception
 Vascular anomaly of the colorectum
 Mesenteric ischemia

18. INVEASTIGATIONS
 Proctoscopy: note number, degree, size, surface and appearance of
piles as well as features of chronicity of the prolapse.
 Sigmoidoscopy or colonoscopy: malignancy
 Endoscopy to rule out other sources of rectal bleeding e.g. cancer and
inflammatory bowel disease.
 Barium enema: malignancy
 Full blood count-check for anemia (hematocrit) and platelet count

19. COMPLICATIONS
 Profuse hemorrhage which may require blood transfusion
 Strangulation- by anal sphincter
 Thrombosis- piles appear dark purple/black, feels solid and tender
 Ulceration
 Gangrene
 Fibrosis
 Stenosis
 Suppuration leads to perianal or submucosal abscess
 Pylephlebitis (portal pyaemia) is rare but can occur in 3rd degree piles
after surgery.

20. ANAL FISTULA(FISTULA IN ANO)
Introduction
 A fistula is an abnormal communication between two
epithelial/endothelial lined surfaces surrounded by granulation tissue.
 A fistula in ano has its external opening in the peri-rectal skin and its
internal opening in the anal canal at the
 Pain is rare with anal fistula. Patients often complain of peri- rectal
itching, irritation and discharge.
 It is believed that fistula in ano can be:
 Crytoglandular (90%) and associated with infection of the intersphincteric
glands
 Non-cryptoglandular (other causes)-10%

21. ETIOLOGY
 Drainage (40%) or rupture of an anorectal abscess (i.e. anal gland
infection) (most common cause)
 Anal fistula forms during the chronic stage of an acute inflammatory
process that begins in the intersphincteric anal glands.
 Extension of the acute inflammation can result in a supralevator,
ischiorectal or perianal abscess.

With chronic inflammation the abscess communicates with the external
surface forming supralevator trans-sphincteric or intersphincteric fistulae.
 Crohn’s disease
 Diverticulitis with perforation and fistula to the perineum
 Infection: HIV, TB, actinomycosis, lymphogranuloma venereum
 Malignancies of the distal rectum, anal canal or perianal skin
 Trauma: foreign body, iatrogenic, anal fissure
 Hydradenitits suppurative

22. CLASSIFICATION
 Fistulae can be either:
 Low level fistulas: these open into the anal canal below the internal ring
 High level fistulas: these open into the anal canal at or above the
internal ring
 Standard classification (Milligan Morgan-1934 and Goligher-1975)
  Pelvi-rectal fistula
  Submucosal fistula
  Subcutaneous (most common)
  High anal fistula
  Low anal fistula(common)
 Park’s classification (1976)
  Intersphincteric fistula commonest)
  Transsphincteric fistula (25%)
  Supralevator/Suprasphincteric fistula (4%)
  Extrasphincteric fistula

23. CLINICAL FEATURES
 Persistent symptoms or ‘non- healing’ following abscess drainage
 Discharge (continuous or
 intermittent) and soiling
 Pruritus
 Rectal pain which may be worse on sitting and defecation
 Untreated can cause sepsis and anatomical changes leading to incontinence
 On examination:  Goodsall’s rule
 Relates to the location of the internal and external openings of a fistula in ano.
 Fistulas with an external opening in relation to the anterior half of the anus is of a direct type.
 If the anus is bisected by a line in the frontal plane, an external opening inferior to that line connects
the internal opening via a short direct tract.
 If the external opening is posterior to the imaginary line, the fistula tract follows a curved route to the
internal opening in the posterior midline, it may present with multiple external openings all connected
to a single internal opening.
 o An exception is an external opening that is anterior to this imaginary line and more than 3cm from
the anus, in which case the tract may be curve posterior and end in the posterior midline.
  Examination under anesthesia if there is significant discomfort
  P/R examination shows indurated internal opening usually in the midline posteriorly.
  Most of the fistulae are on posterior half of the anus.

24. INVESTIGATIONS
 Simple fistulas are diagnosed clinically
 Chest X-ray, ESR and barium enema X-ray.
 If required fistulogram is done only under anaesthesia
 MRI/MRI fistulogram is ideal
 Endorectal U/S (US perineum) is useful to assess deeper plane.
 Dscharge study, methylene blue dye study, biopsy
 Colonoscopy often when ulcerative colitis/Crohn’s is suspected
 Specific blood test

25. ANORECTAL ABSCESS
Introduction
 Anorectal abscess is due to obstruction of anal glands/crypts at the dentate line with
subsequent infection by gut
bacteria.
 Locations include:
 Perianal (60%): limited to skin of anal canal. It results when pus spreads downwards
between the 2 sphincters. It manifests as a tender swelling of the anal verge
 Ischiorectal (20%): crosses the external anal sphincter. It iis formed if a growing
intersphincteric abscess penetrates the external sphincter below the puborectalis.
Infection can spread into the fat of the ischiorectal fossa and the abscess can
become quite large
 Intersphincteric: between the internal and external sphincters. It results from
infection in the anal glands. Fecal coliforms are typically the offending organisms. As
the abscess enlarges within the intersphincteric plane, it can spread in any several
directions.
 Supralevator (Rare): superior extension above levator. It develops when an
intersphincteric abscess expands upwards between the internal and external
sphincters
 Abscess rupture, spontaneous or surgical leads to fistula formation in 50% of
patients

26. RISK FACTORS
 These may cause abscess formation via anal gland infection and/or
separate mechanisms:

Bowel inflammation: IBD (especially Crohn’s), diverticulitis, TB,
 Hidradenitis suppurativa
 Immunosuppression: diabetes, HIV
 Trauma: rectal foreign bodies, receptive anal sex
 Demographic and social: male, aged 20-60

27. CLINICAL FEATURES
 Perianal pain and pruritus. Pain may be worse on siting and defecation
 Constipation due to painful defecation
 Deeper abscesses may cause systemic symptoms
 On Examination:
  Perianal swelling (external or felt by P/R)
 Purulent/bloody discharge
 Examination under anesthesia if there is significant discomfort

28. INVESTIGATIONS
 Can often be diagnosed clinically.
 Deeper abscesses may require endoanal US or MRI

29. DIFFERENTIAL DIAGNOSIS
 Pilonidal abscess
 Hydradenitis suppurativa
 Folliculitis
 Periprostatic abscess
 Bartholin gland abscess
 Inflammatory bowel disease
 Actinomycosis
 Tuberculosis

30. ANAL FISSURE
Introduction
 An anal fissure is a tear in the anal canal, frequently associated with
sudden pain or bleeding during defecation.
 The longitudinal tear (ulcer) in the anal canal can occur anywhere from
below the dentate line to the anal margin.
 90% of anal fissures are in the 6 O’clock position. It may be associated
with skin tags or a sentinel pile.

31. CAUSES
 Straining in constipation
 Childbirth
 Trauma
 IBD

32. PILONIDAL SINUS
Introduction
 A pilonidal sinus is a hair- containing sinus or abscess that usually involves
the skin and adjacent tissue in the intergluteal region.
 Most patients have pain, swelling and drainage when these sinuses become
infected.
 Most investigators believe that this condition is caused by ingrowth of hair,
although whether it is acquired or congenital is not known
 Pilonidal disease can occur at any age but is most prevalent between
adolescence and the third decade of life.
 Recurrent infections are common.
 The treatment depends on the phase of the disease at presentation.
 Pilonidal abscess is best treated by incision and drainage. However, for a
 pilonidal cyst, results of treatment remain imperfect although numerous
methods have been reported. The simplest methods of treatment are
incision and drainage, and curettage with secondary healing or cyst
excision and closure.