Anal Fistula and Anal Abscess

Anal fistula and anal abscess result from an infection of an anal crypt, whose distal end lies near the dentate line. The anal glands, which lie within the intersphincteric groove and empty into the anal crypts, become infected because of impacted feces. The resulting infection makes its way into the intersphincteric space but generally does not penetrate beyond the external sphincter. Most of the anal glands lie posteriorly; therefore, most abscesses drain from a line posterior to the ischial tuberosities, whereas anterior abscesses drain radially from their points of origin. The presence of a rectal fistula or abscess may point to an internal bowel disease such as diverticulitis, trauma to the area, or immune system incompetence, as with the human immunodeficiency virus (HIV).

Under normal conditions the highly vascularized rectal mucosa is able to provide adequate protection against the spread of infection. The weak points are the anal glands, however, because they may become impacted with fecal matter, setting up an infective process in the anal crypt and intersphincteric space. The surrounding perianal tissue is swollen, red, and painful to palpation. If the infection remains in the intersphincteric space, the patient has rectal pain seemingly without specific findings. Eliciting the pain with pressure upon examination may provide a clue to the source of the lesion. The patient may also present with a fever of unknown origin.

The adjacent ischiorectal fossae are regions filled with fatty tissue that allow for distention of the rectum. Therefore, an abscess has many different directions in which to track, setting up areas for pockets of pus. In a true perianal abscess, incision and drainage are usually not recommended because the bulk of the lesion would remain untouched owing to the probable invasion of the underlying tissues and the propensity of such an access to form caverns of pus. Unlike other abscesses formed by the body, perianal abscesses should not be allowed to come to a head and rupture on their own; such an occurrence can lead to excessive inflammatory necrosis of the anal sphincter.

Generally a surgical consultation is warranted for a rectal abscess. Surgery allows for opening of the tract and healing by second intention. However, localized treatment can be undertaken to help the abscess drain if it has ruptured on its own or the patient presents acutely and immediate referral is not possible. Such treatment affords some relief and helps decrease the morbidity associated with this condition. Irrigation with herbal antibacterial agents such as Hydrastis, Usnea, and Calendula succus in 0.9% saline helps drainage.

Another, often encountered scenario is that of folliculitis with resultant abscess formation. These abscesses can be incised and drained, because they do not involve the anal canal or ischiorectal fossa. Homeopathic medicines such as calcarea sulphuricum, silicea, hepar sulphuris, and Myristica are some of the more often indicated medicines. Poultices made of onion, garlic, or potatoes exert a drawing action, bringing the lesion to a head faster. Alternating hot and cold sitz bath is also useful. Once the abscess has broken open or has been incised and drained, irrigation with the previously mentioned solution hastens healing.

Anal Cryptitis

Anal crypts are pockets created between the grooves formed by the rectal columns at their distal points ending at the dentate line. Anal glands empty into the crypts and, as previously mentioned, are believed to be the source of anal fistula. That anal cryptitis is a separate entity is open to some debate, and it is rarely seen. The patient complains of pain that is worse with bowel movement. Examination shows localized tenderness and redness at the dentate line, and there may be some rectal spasm. Rectal fissure should be ruled out. Chronic cases suggest bacterial infection, usually gonorrhea.

Treatment is by herbal suppository, sitz baths, increasing dietary fiber intake, and, if necessary, localized anesthesia. The crypt may be cleaned out with a crypt hook if needed and irrigated with a solution of Calendula succus and Hydrastis in normal saline.

Anal Fissure

An anal fissure is a slit-like separation of the anal mucosa lying below the dentate line. The majority of fissures are found in the posterior midline region (70% to 80%), but anterior midline lesions (10% to 20%) are more commonly seen in women. Some investigators report that fissures are more common in men than women,⁴ but other studies do not bear this out.⁵ In some patients the anal sphincter is more oval than round, coming to a Y or narrow point at the posterior midline, making for a greater predisposition for anal fissure. Anal fissure in children is not all that uncommon, often being associated with chronic diarrhea or hard stool.⁶ Fissure may also be a complication of a lesion associated with a congenital anal deformity. Lesions located in the anteroposterior vertical axis suggest an internal bowel disease, such as Crohn’s disease, squamous cell carcinoma or adenocarcinoma of the rectum, syphilitic fissure, or ulceration due to tuberculosis.

Anal fissures are very painful because of their somatic innervation, which results from spasm of the anal sphincter in response to stretching during the passage of stool. The presence of an anal fissure triggers a vicious cycle of pain, causing sphincter spasm, which contributes to a tightening of the sphincter and increased pain with passage of stool. Patients usually have severe pain during and for some time after defecation, and bleeding is not uncommon. As the lesion enlarges it may ulcerate and become infected. Conventional medical treatment consists of rectal dilation, internal sphincterotomy, electrodessication, or surgical excision.⁵

Anal fissure can be caused by passage of large hard stools, childbirth trauma, chronic diarrhea, trauma, food allergy, or prolonged straining to pass stool. Infants and young children who consume large amounts of cow’s milk are more likely to have anal fissures and chronic constipation, especially if they were breast fed for a shorter period.⁷ Many of the patients in whom anal fissures develop display intense, compulsive personalities that may contribute to the formation of such fissures as well as the ability to heal. A previous anal or rectal operation, syphilis, or Crohn’s disease also predisposes the patient to fissure development.

Examination may be difficult because of the pain and spasm, and anoscopic examination is often out of the question unless anesthesia is used. A localized injection of 1% or 2% lidocaine into the rectal sphincter at the 3-o’clock and 9-o’clock positions can help relax it enough for an examination to occur. One can often see anal fissures without using an anoscope simply by pulling back on the anal skin and examining the tissue. Presence of a sentinel pile or enlarged papilla suggests chronic anal fissure and is the result of inflammation and the body’s attempt to protect the inflamed area. Anal spasm may be marked, making it difficult to perform an examination, and anal stenosis and fibrosis may be present if the condition has been chronic.

Clinicians should consider the presence of Crohn’s disease, especially if the patient is younger, there is a history of periodic or chronic diarrhea, and the fissure lies in the anteroposterior vertical axis. Squamous cell carcinoma, syphilitic ulcers, and rarely tuberculosis should be considered as part of the differential diagnosis. Spasm of the levator ani muscle may also make one think of anal fissure, but no lesion is present in this case.

Treatment of anal fissure can prove to be one of the more difficult courses of therapy for both the patient and the clinician. Although surgical intervention removes the lesion and alleviates the pain, the lesion invariably returns because the underlying cause has not been addressed. Additionally, surgical intervention often predisposes to fecal incontinence later in life. Therefore, medical management both in the short and long terms is necessary for complete resolution. Patients must be cautioned that the healing of a rectal fissure has its periods of exacerbation and remission and that continuing with the treatment protocol is important despite the periodic setbacks that are often encountered. Educating the patient on this point upon initiation of therapy is essential to its success.

Treatment

Initial treatment should be to alleviate the pain and spasm, because often they have brought the patient to the office. Homeopathic medicines provide prompt relief if the simillimum is found and aids the healing process. Remedies such as Chamomilla, graphites, nitric acid, Ratanhia, Sepia, silicea, and Thuja are some of the more often indicated medicines, but others may also be needed.^8,9 Frequent dosing is generally the rule. Protease 315 mg, two capsules three times daily between meals and again before bed, will help to alleviate pain as well. A preparation of 0.2% glycerol trinitrite can be used topically to relieve rectal spasm,¹⁰ as can 5% lidocaine cream for localized pain. Glycerol trinitrite has been shown in a number of studies to be effective in relieving rectal spasm as well as increasing blood flow to the anal sphincter.^11–13 Reduced blood flow to the anal sphincter has been postulated as one of the precipitating mechanisms for the development of an anal fissure.

A topical cream consisting of vitamins A and E, panthenol, Calendula, and Comfrey will considerably enhance the healing process by providing nutrients essential for healing by second intention. Some of the commercial preparations also contain boric acid, which acts as a styptic. Initially, the cream should be applied topically after every bowel movement and at bedtime. As healing occurs, twice-daily application usually suffices until the lesion has resolved.

Iontophoresis using a zinc electrode and applying a positive current helps facilitate healing by hardening the underlying fissure, decreasing bleeding, and affording pain relief.¹⁴ The patient lies on the negative dispersing pad and current is applied for 10 minutes at 10 mA.

The patient should be instructed not to strain during passage of stool and to use cotton balls that have been moistened with water rather than toilet paper or chemical or alcohol wipes. Some patients are excessive cleaners; they should be instructed that it is unnecessary to wipe deep into the anal canal because doing so makes the condition worse.

Sitz baths also aid in the healing process by providing increased blood flow to the area. If performing a sitz bath is not possible, alternately spraying hot and cold water on the perineal area will achieve the same result.¹⁵

Increasing dietary fiber is necessary if the condition is due to chronic constipation, whereas chronic diarrhea can be managed through a variety of therapeutic approaches once the cause is found. Dietary changes are a must, especially if the anal fissure is associated with irritable bowel syndrome or Crohn’s disease. The higher rates of hemorrhoids and Crohn’s disease seen in blood group O individuals are believed to be due to food intolerance.¹⁶

As previously mentioned, the clinical course varies from patient to patient and seems to depend partially on whether the patient follows the treatment plan religiously. Frequent follow-up is needed to assess the healing process and reassure the patient. Once healing has occurred, proper bowel function and good dietary and bowel habits must be maintained in order to prevent further episodes. Patients who experience an anal fissure are at risk for further episodes.

Classification

Hemorrhoids are typically classified according to location and degree of severity. External hemorrhoids occur below the anorectal line. They may be full of either blood clots (thrombotic hemorrhoids) or connective tissue (cutaneous hemorrhoids). A thrombotic hemorrhoid is produced when a hemorrhoidal vessel has ruptured and formed thrombus, whereas a cutaneous hemorrhoid consists of fibrous connective tissue covered by anal skin. Cutaneous hemorrhoids can be located at any point on the circumference of the anus. Typically, they are caused by the resolution of a thrombotic hemorrhoid; that is, the thrombus becomes organized and replaced by connective tissue.

Internal hemorrhoids occur above the anorectal line. Occasionally an internal hemorrhoid enlarges to such a degree that it prolapses and descends below the anal sphincter. Internal hemorrhoids are graded by the degree of prolapse.

Internal-external, or mixed, hemorrhoids are a combination of contiguous external and internal hemorrhoids that appear as baggy swellings. The following types of mixed hemorrhoids can occur:

Treatment

In contrast to the United States and the United Kingdom, hemorrhoids are rarely seen in parts of the world where high-fiber diets containing unrefined foods are consumed.¹⁹ A low-fiber diet high in refined foods contributes greatly to the development of hemorrhoids. Individuals consuming a low-fiber diet tend to strain more during bowel movements, because their smaller and harder stools are more difficult to pass. This straining raises the pressure in the abdomen, obstructing venous return. The greater pressure will increase pelvic congestion and may significantly weaken the veins, causing hemorrhoids to form.

A high-fiber diet is perhaps the most important component in the prevention of hemorrhoids. A diet rich in vegetables, fruits, legumes, and grains promotes peristalsis because many fiber components attract water and form a gelatinous mass that keeps the feces soft, bulky, and easy to pass. A high-fiber diet leads to significantly less straining during defecation.

Natural bulking compounds can be used to reduce fecal straining. These fibrous substances, particularly psyllium seeds and guar gum, possess a mild laxative action owing to their ability to attract water and form a gelatinous mass. They are generally less irritating than wheat bran and other cellulose fiber products. Several double-blind clinical trials have demonstrated that supplementing the diet with bulk-forming fibers can significantly reduce the symptoms of hemorrhoids (bleeding, pain, pruritus, and prolapse) and improve bowel habits.^21,22 The use of psyllium seed fiber has been shown to afford significant relief in bleeding and pain within 6 weeks in hemorrhoid suffers.²³

A placebo-controlled randomized study evaluated the efficacy of fiber supplements in 50 patients with bleeding internal hemorrhoids. Patients in the study group were treated with a commercially available preparation of Plantago ovata and those in the control group were treated with a placebo. Endoscopy was performed in every patient before and after treatment to establish the degree of hemorrhoidal prolapse as well as the numbers of congested hemorrhoidal cushions and contact-bleeding hemorrhoids. During the first 15 days of treatment, the average number of bleeding episodes was 4.8 ± 3.8 for the study group versus 6.4 ± 3 for the control group (NS). During the following 15 days, it decreased to 3.1 ± 2.7 in the study group versus 5.5 ± 3.2 (P <0.05) in the control group, and in the last 10 days of treatment a further reduction to 1.1 ± 1.4 was found in the study group compared with 5.5 ± 2.9 in the control group (P <0.001). The number of congested hemorrhoidal cushions diminished from 2.6 ± 1 to 1.6 ± 2.2 after fiber treatment (P <0.01) but no differences were found in the control group. In the fiber group, hemorrhoids bled on contact in 5 out 22 patients before treatment and in none after treatment; no differences were found in the control group. No modification of the extent of prolapse was observed after treatment.²⁴ Although the effect took a few weeks to develop, the final results were very impressive.

Another important, but only recently recognized dietary factor is breakfast. An age-, gender-, and pregnancy-matched case-control study carried out in an outpatient clinic found a remarkable 7.5-fold increase in the odds of suffering from hemorrhoids or anal fissures in matched subjects who did not eat breakfast!²⁵

Flavonoid preparations have been shown to be beneficial in the prevention and treatment of hemorrhoids through their strengthening effect on venous tissues. Although early studies primarily used rutin, later research has used hydroxyethylrutosides (HERs).

Several of the studies have been performed in pregnant women, where HERs were shown to be of great benefit in helping to relieve hemorrhoidal signs and symptoms. In one study, 90% of the women given HERs (1000 mg daily for 4 weeks) experienced improvement of symptoms, compared with only 12% in the placebo group.²⁶ Similar results in hemorrhoids not associated with pregnancy have been reported.^27,28 Another study provided a micronized flavonoid combination (diosmin 90% and hesperidin 10%) for a median of 8 weeks before delivery and 4 weeks after delivery to 50 pregnant women with acute hemorrhoids. Their therapy was very successful, with 66% of patients reporting relief from symptoms by the fourth day of treatment and fewer suffering relapses during the antenatal period.²⁹ Treatment was well accepted and did not affect pregnancy, fetal development, birth weight, infant growth, or feeding.

In most circumstances, topical treatments for acute or chronic hemorrhoids involving the use of suppositories, ointments, and anorectal pads provide only temporary relief. Many over-the-counter products for hemorrhoids primarily contain natural ingredients, such as witch hazel (Hamamelis), cocoa butter, Peruvian balsam, zinc oxide, allantoin, and homeopathic preparations. Many patients use hydrocortisone cream to help with the itching that they associate with hemorrhoids; prolonged use of this agent can often aggravate the pruritus ani, setting up a cycle of continued use.