Anal abscess and fistula

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Anal abscess and fistula is a frequent disease that cause inflammations and fluid discharge. Treatment of Anal abscess- fistula is at times difficult and the condition may occasionally reappear.


Fistula or abscess?


Perianal abscess is the acute- abrupt- painful phase. fistula is the long- lasting relatively painless phase with pus discharge. Flareups and remissions are quite common.  A perianal abscess appears as a painful swelling, accompanied rarely with fever. Pus and inflammation should be treated as an emergency by surgical drainage of pus. Postoperatively a skin opening with pus discharge is left. This is the clinical appearance of a perianal fistula.




Perianal inflammation is caused from an infection in an inner anal opening. In case of hidradenitis, a skin disease, there is no intraanal opening. Hidradenitis is more frequent in obese and smokers. Rarely, anal fistulas are a manifestation of Crohn’s disease or after external blunt injury or a foreign body ingestion. Other rare types of anal fistula are postoperative fistulas, fistulas after pouch surgery, low anterior resection, anovaginal or rectoprostatic fistulas.




The abscesses occur suddenly, within a few days, as a painful inflamed swelling and occasionally fever. The fistulas appear like an opening with pus discharge. Skin openings may heal or reappear.  is, there are multiple skin openings and fistulas are seen in hydradenitis. Rarely fistulas are early diagnosis of fiustulas can be made with the finding of a painful intraanal bulge only.


Diagnosis and preoperative diagnosis


An important feature in the diagnostic assessment of perianal fistulas and their proper surgical treatment is the exact location of internal opening in the anal canal. Other significant features of preoperative assessment are fistula’s connection with the anal sphincters (circular muscles which hold the stools) and the proportion of sphincters beneath the fistula. Manual examination by an experienced surgeon may provide significant information about fistula anatomy. A frequently employed diagnostic test is NMR. However, in our practice we use 3d endoanal ultrasound for 25 years. Because of our long-term experience with 3d ultrasound, we are able to obtain an immediate diagnosis concerning perianal inflammation, and additionally an extremely detailed information about significant features of fistula tract and its relationship to anal sphincters. 3d ultrasound gives us the ability to make measurements in millimeters. The MRI usually gives indefinite answers to the above questions and it is completely wrong in the worst of cases.


Treatment – Techniques (laser)


Abscesses containing pus should be treated by opening the abscess and draining pus. If the surgery is delayed, abscesses get worse and the patient may endure quite important pain. Rarely septicemia with hypotension may occur. If abscesses are not eventually drained upon, they eventually drain by themselves and pus. comes out by itself.  However, in this instance the abscess has expanded a lot, it may penetrate deeper into anal sphincters and the final treatment of fistula becomes more complicated. Because abscesses usually originate from an anal opening, postoperatively a fistula often remains with pus discharge from a skin opening. This condition should be treated in a second phase. The opinion that the poor drainage of the abscess causes the fistula is totally wrong. In selected cases a complete treatment of anal fistula-abscess can be achieved in one surgical procedure by a proctologist-surgeon and after a detailed 3d ultrasound.


Antibiotics should be given as a unique treatment of perianal abscess only when an untrained surgeon cannot detect the abscess, especially if there is no preoperative diagnostic assessment. Antibiotics often manage to limit inflammation, and the later often recurs to a greater extent. There are more than ten available techniques for fistula treatment. The existence and use of such a large number of surgical procedures indicate that none is appropriate for all kind of fistulas. The main purpose is at first not to damage anal sphincters, secondarily to definitely treat the fistula and third not to cause an extensive wound and severe postoperative disablement. In recent years a great number of procedures and appliances have been proposed as golden treatment of fistulas. In their introduction they have been advertised as a final solution with important financial and advertising benefits to the medical providers, but with time all their disadvantages come to the surface.


The oldest and simplest technique is to lay open the fistula. The use of a seton (loose or tight) suture for more difficult fistulas has been used since Hippocratic era. In recent years many new techniques have been devised (LIFT, Flap, AFP, Permacol, VAAFT, OTSC, etc.). Some appear and disappear as comets after their disadvantages emerge. Filac-Laser technique in certain cases is a method that promises a lot because it does not cause any injury and does not injure sphincters. Its success rate, according to the inventor of the method, is about 60-70%.


Any proctologist surgeon operating fistulas should not limit his armamentarium in one technique only but should look for the appropriate procedure in every individual patient. For a particular fistula surgery in a patient, we may use a combination of two or more techniques at the same time for the best result. Some fistulas can be cured within half an hour. More difficult fistulas require patience and more than one surgical procedures for a satisfactory outcome. The most important goal for a fistula patient is the suited selection of the proctologist-surgeon. If a bilateral trusted relationship between patient and surgeon has been established, a definitive treatment is very likely. In difficult cases the patient must be patient.


Postoperative course


After a laser surgery, wherever it can be applied, there is no trauma and the patient can return to his activities in a couple of days. In the other methods, it may have another kind of surgical wound with discharge. This usually requires proper wound care and frequent dressings.