Patients with anal fissures usually present with pain and bleeding. Pain is often most severe during or after a bowel movement, while bleeding is usually bright red and minimal. An accurate diagnosis can often be made on the basis of the patient's history. The American Gastroenterological Association has issued recommendations on the diagnosis and management of anal fissures.
The diagnosis is based on the classic symptoms and a split in the epithelium at or within the anal verge, which is visualized best with lateral traction applied to the opposite buttock. Other physical findings of chronicity include a distal skin tag or a proximal thickened anal papilla. Trauma is the most common etiology, although some patients report only a single episode of diarrhea. It is probably a chronic increase in resting anal pressure with resultant anodermal perfusion that causes fissure events and recurrences. Endoscopy or evaluation with an instrument is usually painful and unnecessary. When required, the physical examination can be done with anesthesia. Most lesions are located in the midline, either anterior or posterior. If the fissure is off midline, evaluation for some other diagnosis, including Crohn's disease, human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) and associated infections, ulcerative colitis, tuberculosis, syphilis, leukemia, or cancer, is required.
Increased fiber and fluid intake, sitz baths, and topical analgesics are the usual measures used in the management of acute fissures, and most fissures heal with minimal care. Emollient suppositories also may be useful. Self-dilation with anal dilators does not have documented efficacy. Chronic fissures, those that do not heal, and highly symptomatic lesions may require additional care.
Further treatment options include surgery, topical therapy, and botulin toxin. Surgery involves a sphincterotomy that rapidly reduces symptoms but occasionally results in fecal incontinence that can be permanent. Topical therapy includes nitroglycerin ointment or topical calcium channel blockers to decrease the resting anal pressure, but these preparations are not presently available in the United States. Headaches and lightheadedness are common in patients using topical nitroglycerin. Topical calcium channel blockers have fewer adverse effects. Botulin toxin can be injected locally into the sphincter (internal or external), with frequent relief of symptoms. Long-term studies of relapse rates and resulting incontinence from this treatment are necessary.
Treatment in patients with Crohn's disease can be more aggressive, but surgery should be withheld initially because of the potential of incontinence or disease progression requiring proctectomy. Standard conservative treatment is the first choice in these patients. Patients with HIV/AIDS must have anal fissures distinguished from anal ulcers, which are broad-based and deep, with generally lower sphincter tone.
The statement and review conclude by noting that conservative therapy is risk-free but may take longer to achieve symptom relief. Sphincterotomy is a more familiar treatment in select cases, but the use of topical therapy and botulin toxin injection are gaining support, even in patients who are less symptomatic.