Fistulo in ano

brief summary about fistula in ano

1. Fistula in ano Mohammed alhinai

2. Fistula in ano : pathological track lined by epithelium which connect two epithelium surface ( connect the lumen of anal canal or rectum with the external perianal surface. Causes Primary : Anorectal abscess ( most common ) secondary : Crohn disease (could cause multiple opening ) Anorectal carcinoma Iatrogenic causes Lymphogranuloma venereum Rectal foreign bodies Actinomycosis Tuberculosis (could cause multiple opening ) Lymphogranuloma venereum ( chronic infection in the lymphatic system caused by Chlamydia trachomatis, and can cause inflammatory perirectal masses) Radiation proctitis (pelvic radiation can develop bleeding, rectal pain, and fistulas) Rectal foreign bodies rare cause ( by anorectal mucosal laceration is the most common complication from anal insertion of a foreign body and can result in an abscess and fistula formation ) Actinomycosis (cause a simple fistula-in- ano or an inflamed perirectal mass in immunocompromised individuals) Tuberculosis ( rarly occur in immunocomprised and and in population with high incidence of tuberculosis ).

3. Externally into perianal skin Internally into anal canal or rectum Mucus and stool force through the fistulous lead to stop healing of fistula by granulation tissue. pathogenesis

4. Clinical features: Age : occur during adult age – rarely in children . Symptoms : Most common symptoms is watery or purulent discharge from external fistula.  intermittent rectal pain if pus collect in fistula aggravated by defecation, sitting and activity . intermittent and malodorous perianal drainage and pruritus Can occasion be bloodstained. Physical examination : Position of fistula : external opening may be visualized, or palpated as induration just below the skin if the external opening is incomplete or blind . Tenderness Discharge Rectal examination : internal opening may felt as area of induration or small nodule below the mucosa. If felt, try to decide as below or above anorectal junction ( low level or high level ).

5. Goodsall’s rule : It help to identify the location of internal opening of fistula by draw transverse line through the c entre of anus : 1- if the external opening of fistula anterior to the line : the track will be in straight line toward the internal opening. 2- if external opening posterior to line : the track will curve as horseshoe manner to open into midline of posterior anal canal

6. Classification of anal fistula: Its important as affect the surgical management and to know the risk of continence of anal sphincter.

7. Then another classification divide the location of internal opening according to ano -rectal ring ( where the puborectalis muscle sling fuse with external sphincter) : 1- low fistula in ano : below the ano -rectal ring which at this level can be laid open the fistula without significant of impairment of continence. 2- high fistula in ano : laying the open of fistula would divide the ano -rectal ring and affect the patient continence.

8. Differential diagnosis: Anal abscess Anal fissure Anal ulcer or sores. Diagnosis Clinical diagnosis (usually) Imaging studies : MRI helpful for diagnostic evaluation of recurrent fistula and exclude other causes MRI best imaging to know the route of fistula. Fistulography and CT scan may help in some cases Endoscopic evaluation : Including proctoscopy or sigmoidoscopy or colonoscopy. helpful for diagnostic evaluation of recurrent fistula and exclude other causes

9. Management: Overall goal of surgery : Eradicate the fistula Preserve anal sphincteric function. Prevent recurrence. The surgical management of fistula depend on Location of fistula in relation to external anal sphincter Amount of sphincter complex involved with fistula tract. According for that, fistula divide into : Simple fistula : minimal involvement of external sphincter muscle low fistula in ano according to location complex fistula : involving more than 30 percent of the external sphincter. High fistula in ano Women with anterior fistulas Fistulas with multiple tracts Recurrent fistulas Fistula caused by secondary causes.

10. Simple fistula : 1- fistulotomy : open the fistula tract in its entirety and promote healing of incision. ( for lower fistula ). Patients should be observed for a minimum of six months following the procedure before determining a treatment failure or success. complication of a fistulotomy is incontinence from procedure-related damage to the external anal sphincter. Recurrence rates for an anorectal fistula are low. 2- fibrin sealant:   mixture of fibrinogen, thrombin, and calcium ions form a clot that is injected into the fistula tract and within 10 to 60 seconds the fistula is potentially sealed. The main benefit of fibrin glue is sphincter preservation . Recurrence is low but higher compare to fistulotomy .

11. Complex fistula : Multiple procedures use, commonly : 1- fistulotomy and setons (higher fistula) : A cutting seton is a reactive suture or elastic that is placed through the fistula tract and tightened at regular intervals A noncutting or draining seton is a seton that is placed primarily for drainage . two most important complications of a fistulotomy with a cutting seton are recurrence and incontinence.

12. Anal fissure

13. Fissure in ano : anal fissure is a tear in the anoderm distal to the dentate line. Passage of hard stool Constipation Prolonged diarrhea Vaginal delivery Anal sex Previous anal surgical procedure. Inflammatory bowel disease ( crohn’s disease ) Granulomatous disease ( extrapulmonary tuberculosis- sarcoidosis ) Malignancy Communicable disease ( HIV infection – syphilis- chlamydia)

14. Pathogenesis: prolong repeated cycle lead to chronic anal fissure. Spasm pull the edge of fissure lead to impair healing Prolong spasm lead to reduce blood supply causing ischemic

15. Location of anal fissure : Most common caused by primary causes. Usually caused by trauma or secondary causes. Indicate serious condition and require to know underlying cause. Colonoscopy and biopsy required.

16. Clinical feature : Less intense pain Small amount of bright rectal bleeding Perianal pruritus or skin irritation Tearing pain increase by passage of bowel movement Small amount of bright rectal bleeding Perianal pruritus or skin irritation

17. Physical examination : Pale with raised edges External skin tag at distal end of fissure (sentinel pile) Hypertrophied anal papillae at proximal end. Fresh laceration like paper cut. Digital rectal examination and anoscopy contraindicated as increase the pain.

18. Diagnosis : clinical diagnosis based on history and physical examination. Lateral anal fissure need to evaluate further to know the underlying causes.

19. Management :