History

Fact Explanation
History of an perianal abscess A fistula is an abnormal connection between two epithelial surfaces. An anal fistula is a tract which usually communicates an infected anal gland to a secondary opening in perianal skin, which is lined with granulation tissue. Cryptoglandular disease (anorectal abscesses ) is responsible for 90% of fistula-in-ano. Anorectal abscesses represent the acute presentation of cryptoglandular disease, while fistulae are the chronic evolution of the same process. There is usually a History of an anorectal abscess that was either drained spontaneously or surgically. He/ she may remember of a discharge, pain, swelling in the perianal area. [1,2,3,4,5]
Discharge The abscess usually discharge pus. This is usually foul smelling yellowish with streaks of blood. The discharge may occur continuously or intermittently. [2,3,4]
Perianal pain If the discharge is intermittent, the patient may have increased pain and pressure prior to recurrent drainage, which gives relief. [3,4,5]
Nonspecific symptoms Other symptoms include bleeding, soreness, pruritis or Skin excoriation (perianal dermatitis). [1,6,7]
Past history of similar events Sometimes perianal fistulas recurs. Patient may give a history of similar event in the past. Most of the patients with perianal fistula have a underlying disease conditions such as Crohn’s disease. [2,3,6]
Risk factors While the Cryptoglandular disease accounts for the most of the perianal fistulae, other less common causes of fistulae are Crohn’s disease, trauma, anal fissures, carcinoma, radiation therapy, tuberculosis, and chlamydial infections. Males in their 30s -40s are more predisposed than females. [1,3,4,7]
References
  1. AJAYI AO, CHANDRASEKAR T, HAMMED AH. Crohn's disease presenting as a recurrent perianal fistula: a case report. Niger J Clin Pract [online] 2010 Dec, 13(4):473-6 [viewed 18 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/21220869
  2. KHERA PS, BADAWI HA, AFIFI AH. MRI in perianal fistulae. Indian J Radiol Imaging [online] 2010 Feb, 20(1):53-7 [viewed 18 August 2014] Available from: doi:10.4103/0971-3026.59756
  3. GILLESPIE WF. The Treatment of Perianal Abscess and Fistula. Can Med Assoc J [online] 1942 Dec, 47(6):547-51 [viewed 18 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/20322639
  4. ABERCROMBIE JF, GEORGE BD. Perianal abscess in children. Ann R Coll Surg Engl [online] 1992 Nov, 74(6):385-6 [viewed 18 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/1471832
  5. TABRY H, FARRANDS PA. Update on anal fistulae: surgical perspectives for the gastroenterologist. Can J Gastroenterol [online] 2011 Dec, 25(12):675-80 [viewed 18 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/22175058
  6. WHITEFORD MH. Perianal abscess/fistula disease. Clin Colon Rectal Surg [online] 2007 May, 20(2):102-9 [viewed 18 August 2014] Available from: doi:10.1055/s-2007-977488
  7. RUFFOLO C, CITTON M, SCARPA M, ANGRIMAN I, MASSANI M, CARATOZZOLO E, BASSI N. Perianal Crohn's disease: is there something new? World J Gastroenterol [online] 2011 Apr 21, 17(15):1939-46 [viewed 18 August 2014] Available from: doi:10.3748/wjg.v17.i15.1939

Examination

Fact Explanation
External opening of the fistula The external opening can be seen as an elevation of granulation tissue in the perianal area, usually within 3cm distance from the anal verge. Spontaneous discharge of the pus can be observed. Or else this may be elicited on the digital rectal examination, as the pus discharges outside through that opening. Rarely several openings may be seen. [1,2,3,4]
Fistula tract Patient is usually in pain. So he/ she may not allow to perform further examinations. If it is allowed, digital rectal examination will permit to palpate a fibrous tract or cord that runs beneath the skin. It is the sinus tract that extends from the external opening to the abscess. According to the Goodsall rule, if the external opening lies anterior to a plane which is transversely passing through the center of the anus, a straight radial course will be followed by the fistula to the dentate line. If the external opening locates posterior to this line, the fistula tract will follow a curved course to the posterior midline. Thus Goodsall's rule gives a general idea of the course of the fistula tract, that can be confirmed by the examination. Rarely, specially when the external opening is located more than 3cm from the anal verge, this rule becomes unreliable. Inability to palpate the fistula tract implies a deeper course and therefore higher transsphincteric fistula. [2,3,4,5,6]
Internal opening Internal openings may be felt during the digital rectal examination as indurated nodules or pits that correspond to enlarged papilla, leading to a thickened tract. [1,2,4,5]
Old surgical scars Scar from earlier procedures may be appreciated as well as chronic skin changes such as thickened and redness from persistent drainage. [3,4,5,6]
Anoscopic examination This examination allows visualization of the dentate line for possible identification of internal openings before surgery, as well as identification of other pathology such as Crohn’s disease or carcinoma. [2,3,5,6]
References
  1. AJAYI AO, CHANDRASEKAR T, HAMMED AH. Crohn's disease presenting as a recurrent perianal fistula: a case report. Niger J Clin Pract [online] 2010 Dec, 13(4):473-6 [viewed 18 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/21220869
  2. RUFFOLO C, CITTON M, SCARPA M, ANGRIMAN I, MASSANI M, CARATOZZOLO E, BASSI N. Perianal Crohn's disease: is there something new? World J Gastroenterol [online] 2011 Apr 21, 17(15):1939-46 [viewed 18 August 2014] Available from: doi:10.3748/wjg.v17.i15.1939
  3. KHERA PS, BADAWI HA, AFIFI AH. MRI in perianal fistulae. Indian J Radiol Imaging [online] 2010 Feb, 20(1):53-7 [viewed 18 August 2014] Available from: doi:10.4103/0971-3026.59756
  4. GILLESPIE WF. The Treatment of Perianal Abscess and Fistula. Can Med Assoc J [online] 1942 Dec, 47(6):547-51 [viewed 18 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/20322639
  5. TABRY H, FARRANDS PA. Update on anal fistulae: surgical perspectives for the gastroenterologist. Can J Gastroenterol [online] 2011 Dec, 25(12):675-80 [viewed 18 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/22175058
  6. WHITEFORD MH. Perianal abscess/fistula disease. Clin Colon Rectal Surg [online] 2007 May, 20(2):102-9 [viewed 18 August 2014] Available from: doi:10.1055/s-2007-977488

Differential Diagnoses

Fact Explanation
Bartholin gland abscess Bartholin’s abscesses occur when the Bartholin’s glands, located on either side of the opening of the vagina, become obstructed and infected. If the gland becomes blocked, a cyst will usually form first. If the cyst becomes infected, it can lead to a Bartholin’s abscess. The abscess can be more than an inch in size and cause extreme pain. [1]
Hidradenitis suppurativa Hidradenitis suppurativa is a skin disease characterized by clusters of chronic abscesses, epidermoid cysts, sebaceous cysts, pilonidal cyst or multilocalised infections that most commonly affects areas bearing apocrine sweat glands, such as the underarms, under the breasts, inner thighs, groin and buttocks. [2]
Pilonidal disease A pilonidal cyst, also referred to as a pilonidal abscess, pilonidal sinus or sacrococcygeal fistula, is a cyst or abscess near or on the natal cleft of the buttocks that often contains hair and skin debris. The exact cause of a pilonidal sinus is unclear, although it is thought to be caused by loose hair piercing the skin which may trigger an inflammatory response to form an abscess. Patients usually presents with an swelling in the cleft of the buttocks. The swelling is painful, tender, warm and reddish. Though the usual site is the skin of the natal clefts, cleft between the fingers, axilla, at the umbilicus, in the perineum or the sole of the foot as well as on the amputation stumps may also be affected. [3]
References
  1. SAEED NK, AL-JUFAIRI ZA. Bartholin's Gland Abscesses Caused by Streptococcus pneumoniae in a Primigravida. J Lab Physicians [online] 2013 Jul, 5(2):130-2 [viewed 18 August 2014] Available from: doi:10.4103/0974-2727.119870
  2. FERNANDES NC, FRANCO CP, LIMA CM. Hidradenitis suppurativa: retrospective study of 20 cases. An Bras Dermatol [online] 2013 May-Jun, 88(3):480-1 [viewed 07 August 2014] Available from: doi:10.1590/abd1806-4841.20131637
  3. VARNALIDIS I, IOANNIDIS O, PARASKEVAS G, PAPAPOSTOLOU D, MALAKOZIS SG, GATZOS S, TSIGKRIKI L, NTOUMPARA M, PAPADOPOULOU A, MAKRANTONAKIS A, MAKRANTONAKIS N. Pilonidal sinus: a comparative study of treatment methods. J Med Life [online] 2014 Mar 15, 7(1):27-30 [viewed 07 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/24653753

Investigations - for Diagnosis

Fact Explanation
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 and poor visualization of anatomic landmarks. This study has been substituted by other imaging techniques. [1,2,3,4,5]
Endoanal Ultrasound Ultrasonography helps in identification of the fistula tract in relation to the internal and external sphincters, to determine if the fistula is simple or complex and to define the location of the internal opening. The injection of hydrogen peroxide into the fistula opening during ultrasound improves identification of fistulae and their internal openings by making them hyper instead of hypoechoic. [2,3,4,5]
MRI scan This is becoming the study of choice in evaluating complex and recurrent fistulae. Accurate classification with MRI is possible than with 2-D ultrasound. But it is best reserved for the cases where ultrasound has already failed in identifying the fistula and internal opening. [1,2,3,5]
Anal Manometry Pressure evaluation of the sphincter mechanism is helpful in patients with a decreased tone This can be observed during the preoperative evaluation, in patients with a history of previous fistulotomy and patients with a history of obstetrical trauma. [1,3,4]
References
  1. RUFFOLO C, CITTON M, SCARPA M, ANGRIMAN I, MASSANI M, CARATOZZOLO E, BASSI N. Perianal Crohn's disease: is there something new? World J Gastroenterol [online] 2011 Apr 21, 17(15):1939-46 [viewed 18 August 2014] Available from: doi:10.3748/wjg.v17.i15.1939
  2. AJAYI AO, CHANDRASEKAR T, HAMMED AH. Crohn's disease presenting as a recurrent perianal fistula: a case report. Niger J Clin Pract [online] 2010 Dec, 13(4):473-6 [viewed 18 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/21220869
  3. TABRY H, FARRANDS PA. Update on anal fistulae: surgical perspectives for the gastroenterologist. Can J Gastroenterol [online] 2011 Dec, 25(12):675-80 [viewed 18 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/22175058
  4. GILLESPIE WF. The Treatment of Perianal Abscess and Fistula. Can Med Assoc J [online] 1942 Dec, 47(6):547-51 [viewed 18 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/20322639
  5. WHITEFORD MH. Perianal abscess/fistula disease. Clin Colon Rectal Surg [online] 2007 May, 20(2):102-9 [viewed 18 August 2014] Available from: doi:10.1055/s-2007-977488

Management - Specific Treatments

Fact Explanation
Watchful waiting For an uncomplicated or asymptomaticcase, drainage seton can be left in place long-term to prevent problems. This is the safest option although it does not definitively cure the fistula. Draining setons will keep the fistulous tract open, allowing for abscess drainage and tract maturation, therefore facilitating a future fistulotomy or other advanced fistula closure technique. [1,2,3,4]
Fistulotomy A probe is passed gently through the tract. Then an incision is made over the probe by a scalpel or electrocautery opening the tract. The edges of the tract are excised completely. Once open, the fistulous tract should be cleaned with a curette to remove any granulation tissue. At the completion of the procedure, light packing tape may be placed in the fistula tract. This option leaves behind a scar, and depending on the position of the fistula in relation to the sphincter muscle, can cause problems with incontinence. Fistulotomy is not suitable for fistulas that cross the entire anal sphincter. [2,3,4,5]
Seton Placement A cutting seton gradually cuts through the sphincter muscle via pressure necrosis, with fibrosis behind the seton, preventing sphincter retraction and incontinence. Care must be taken to not advance the seton too quickly, as the patient will experience a tremendous amount of pain as well as suffer a complication of sphincter division. [3,4,6,7]
Fibrin Glue Fibrin glue may be used as an alternative means of occluding the fistulous tract. When applied to the fistula tract, the fibrin clot seals the tract and stimulates migration, proliferation, and activation of fibroblasts. [2,3,6,7]
Anal Fistula Plug This fistula plug made from lyophilized porcine intestinal collagen is designed to occlude the fistula tract from the internal to the external opening. The plug provides a scaffold for the ingrowth of native tissue. [4,6,7]
Endorectal flaps This treatment modality consists of removal and patching of the internal opening with a muscular–mucosal flap of rectal wall. In patients with chronic high fistula a mucosal advancement flap is used.[3,4,6]
Ligation of the intersphincteric fistula tract (LIFT) LIFT technique is the novel modified approach through the intersphincteric plane. LIFT procedure is based on secure closure of the internal opening and removal of infected cryptoglandular tissue through the intersphincteric approach. [3,6,7]
References
  1. AJAYI AO, CHANDRASEKAR T, HAMMED AH. Crohn's disease presenting as a recurrent perianal fistula: a case report. Niger J Clin Pract [online] 2010 Dec, 13(4):473-6 [viewed 18 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/21220869
  2. KHERA PS, BADAWI HA, AFIFI AH. MRI in perianal fistulae. Indian J Radiol Imaging [online] 2010 Feb, 20(1):53-7 [viewed 18 August 2014] Available from: doi:10.4103/0971-3026.59756
  3. TABRY H, FARRANDS PA. Update on anal fistulae: surgical perspectives for the gastroenterologist. Can J Gastroenterol [online] 2011 Dec, 25(12):675-80 [viewed 18 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/22175058
  4. ABERCROMBIE JF, GEORGE BD. Perianal abscess in children. Ann R Coll Surg Engl [online] 1992 Nov, 74(6):385-6 [viewed 18 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/1471832
  5. GILLESPIE WF. The Treatment of Perianal Abscess and Fistula. Can Med Assoc J [online] 1942 Dec, 47(6):547-51 [viewed 18 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/20322639
  6. WHITEFORD MH. Perianal abscess/fistula disease. Clin Colon Rectal Surg [online] 2007 May, 20(2):102-9 [viewed 18 August 2014] Available from: doi:10.1055/s-2007-977488
  7. RUFFOLO C, CITTON M, SCARPA M, ANGRIMAN I, MASSANI M, CARATOZZOLO E, BASSI N. Perianal Crohn's disease: is there something new? World J Gastroenterol [online] 2011 Apr 21, 17(15):1939-46 [viewed 18 August 2014] Available from: doi:10.3748/wjg.v17.i15.1939