Definition of anal fistula An anal fistula is a fistula in the anus. Most fistulas are formed when an anorectal abscess breaks down or is incised to drain the pus. The abscess gradually shrinks, but the intestinal contents continue to enter the abscess cavity, in the process of healing and shrinking, often forming a tortuous cavity, poor drainage is not easy to heal, and after a long time there are many scar tissue around the cavity, forming a chronic infectious pipeline. In Chinese medicine, this disease is called “hanging carbuncle”, “sitting horse carbuncle”, “dirty poison”, etc. It is mostly caused by the rupture of perianal abscesses around the rectum and the formation of granulomatous canals around the anus that do not heal over time. It mostly occurs in men aged 20 to 40. Anal fistulas generally consist of a primary internal opening, a fistula arm, and a secondary external opening. Most of the internal openings are located near the dentition line, mostly one, and the external openings are located on the perianal skin and can be one or more. Anal fistula is a common anal disease. Anal fistula mainly invades the anal canal and rarely involves the rectum, so it is often referred to as anal fistula, also called “anal leakage” in Chinese medicine. It is a granulomatous canal that connects to the skin of the perineum. The incidence of the disease is second only to hemorrhoids and is most often seen in male young adults, probably due to the high secretion of sebaceous glands, one of the target organs of male sex hormones. The cause of anal fistula 1, the presence of the inner mouth of the primary source of infection such as anal sinusitis, or anal gland infection still exists, the contents of the intestinal cavity can also continue to enter the fistula from the inner mouth, again forming a new fistula. This is the key to the recurrence of anal fistula. The actual fact is that you will be able to find all of them, just eliminate the surface of the fistula, and not solve the most critical internal mouth, resulting in repeated attacks of anal fistula. 2, the anal part can not be static, the pus cavity is not easily bonded in feces, urination, due to sphincter muscle contraction or due to inflammation stimulation of the anal sphincter muscle, so that the anal sphincter muscle is often in spasm. 3, the intestinal cavity of the feces, intestinal fluid and gas continue to enter the fistula, stimulating the wall of the tube, so that the wall of the connective tissue hyperplasia thickened, the lumen is difficult to close. 4, poor drainage of the abscess cavity, or narrowing of the external mouth, sometimes closed and sometimes collapsed, pus accumulation in the cavity, resulting in abscess recurrence and penetration and the formation of new branches or fistulas. 5, the tube more than at different heights through the anal sphincter, sphincter contraction impede the discharge of pus, resulting in poor drainage. In addition, there are some diseases that are also the cause of the formation of anal fistula, such as tuberculosis Clon’s disease, ulcerative colitis, etc. 6, children’s sacral bend has not yet formed, the tension of the internal anal sphincter is weak, feces easy to directly press the anal canal at the tooth line, the anal sinus mucosa abrasion, easy to make the bacterial invasion caused by disease. 7, children often due to diaper dermatitis, stimulation of the skin around the anus, the formation of perianal subcutaneous abscess and anal sinus, and become anal fistula. 8, neonatal sebaceous gland hypersecretion, infection formed perianal subcutaneous abscesses and anal sinus, and anal fistula. 9, neonatal physiological immune insufficiency, prone to anal infection, the formation of anal fistula. The symptoms of anal fistula 1, poor anal venous reflux, frequent local bruising, tissue malnutrition, affecting healing. 2, the fistula is bent, or has sinuses, branches, poor drainage, retention of pus, repeated infection, resulting in fistula is not easy to heal. 3, there is a certain pressure in the rectum, will rectal infection material such as feces, gas, can often constantly from the inner mouth into the fistula, stimulate the cavity wall, secondary to infection from the outer mouth, is also the cause of fistula. 4, after the perianorectal abscess breaks, the pus is discharged, the pus cavity gradually shrinks, the external rupture and incision also shrinks, and the cavity wall forms a hard duct wall with proliferation of connective tissue, and thus cannot be closed naturally. 5, fistula passage between the anal sphincter, because the sphincter often constantly contract and diastolic, compression of the fistula, affecting the exclusion of pus, easy to store pus infection and difficult to heal. 6, anorectal perineal abscess breaks or incision mostly outside the anus, pus flows from the external mouth, but the primary infection is mostly in the anal sinus. The anal sinus is then the portal of secondary infection, repeatedly infected and forming a fistula. 7, abscesses formed by infections such as Mycobacterium tuberculosis and Actinomyces, and Clonorchisis, which are difficult to heal by themselves and form special anal fistulas. Most anal fistulas are formed by anorectal abscesses after breaking or incision and drainage of pus. The abscess gradually shrinks, but the intestinal contents continue to enter the abscess cavity, and in the process of healing and shrinking, tortuous cavities are often formed, which do not drain well and do not heal easily. Traveling in the vicinity of the internal and external sphincter, the skin of the external mouth grows faster, often with pseudo-healing, causing recurrent episodes. The majority of infections in the canal are purulent, and a few are tuberculous. The danger of anal fistula 1, anal fistula infection inflammation, anal pain is intense, ulcerated pus contamination of underwear, pus stimulation of local skin, anal itching intense. The more frequent the attacks are, the more frequent they are, forming a mutual cause and effect. The first thing you need to do is to get a good idea of what you are getting into. 3, multiple anal fistula, can form rectovaginal fistula, rectal urethral fistula and rectal bladder fistula, endangering the surrounding organs, and years of untreated or mistreated old anal fistula has the possibility of cancer. The first thing you need to do is to get a good idea of what you are getting into. The fistula of low anal fistula can be felt under the skin as a rope-like hard strip that travels from the external mouth to the anus, and when pressed with the finger, pus flows from the external mouth. The external opening is often seen as a protrusion or depression on the skin around the anus or on the buttocks. The surrounding skin is often red and peeling due to pus stimulation, and sometimes there is granulation tissue protruding from the external opening. If the surrounding skin is red-purple, it is mostly a tuberculous fistula. 3. Rectal examination A small hard node with a depressed center can often be felt on the posterior side of the anal canal, near the dentate line, with slight pressure pain, which is the primary internal orifice. 4.To determine the location of the internal orifice, pathological examination and bacterial culture, medical history to determine the location of the internal orifice, iodine oil imaging, anoscopy, the distance between the external orifice and the anus to determine the location of the internal orifice, staining examination, examination by probing and palpation can help to understand the location of the internal orifice. Note: When suffering from anal diseases, do not listen to the so-called treatment prescriptions advertised, but always go to a regular public first-class hospital for treatment.