Symptoms of Fistula (Anal Abscess)
Anorectal pain, swelling, perianal cellulitis (redness of the skin) and fever are the most common symptoms of an abscess. Occasionally, rectal bleeding or urinary symptoms, such as trouble initiating a urinary stream or painful urination, may be present.
Patients with fistulas commonly have history of a previously drained anal abscess. Anorectal pain, drainage from the perianal skin, irritation of the perianal skin, and sometimes rectal bleeding, can be presenting symptoms of a fistula-in-ano.
Major Causes
Most anal fistulas are the result of an infection that starts in an anal gland. This infection results in an abscess that drains spontaneously or is drained surgically through the skin next to the anus. The fistula then forms a tunnel under the skin and connects with the infected gland.
Diagnosis of Fistula (Anal Abscess)
A careful history regarding anorectal symptoms and past medical history are necessary, followed by a physical examination.
Most anal abscesses and fistula-in-ano are diagnosed and managed on the basis of clinical findings. Occasionally, additional studies can assist with the diagnosis or delineation of the fistula tunnel. Endoanal ultrasound are a very effective manner of diagnosing a deep perirectal abscess, identifying a horseshoe extension of the abscess, and delineating the path of a fistula tract. This may be combined with hydrogen peroxide injection into the fistula tract (via the external opening) to increase accuracy. MRI scans can be useful for patients with complicated infections or with other medical conditions which may present similarly, such as Crohn’s disease. A pelvic MRI may also be performed for mapping the fistula tract and identifying internal openings.
Treatment of Anal Abscess
The treatment of an abscess is surgical drainage under most circumstances. An incision is made in the skin near the anus to drain the infection. This can be done in a doctor’s office with local anaesthetic or in an operating room under deeper anaesthesia. Hospitalization may be required for patients prone to more significant infections, such as diabetics or patients with decreased immunity.
Up to 50% of the time after an abscess has been drained, a tunnel (fistula) may persist, connecting the infected anal gland to the external skin. This typically will involve some type of drainage from the external opening. If the opening on the skin heals when a fistula is present, a recurrent abscess may develop. Until the fistula is eliminated, many patients will have recurring cycles of pain, swelling and drainage, with intervening periods of apparent healing..
Treatment of Anal Fistula
Currently, there is no medical treatment available for this problem and surgery is almost always necessary. Our modality of treatment is Laser surgery
Yet another non-sphincter dividing treatment for anal fistula is the LIFT (ligation of the intersphincteric fistula tract) procedure. This procedure involves division of the fistula tract in the space between the internal and external sphincter muscles. This procedure avoids division of the sphincter muscle, but has not been performed long enough to adequately assess its success or the most appropriate cases to attempt it on.
