Chronic Anal Pain

Abstract

Chronic anal pain is the endpoint for a wide range of pathologies. It affects as much as 6.6 % of the population, though only about a third of those affl icted consult a physician [ 1 ]. It can be a disabling condition, with signifi cant decrease in quality of life, psychological distress, and inability to work. Compounding the issue is the relatively sparse data available to aid clinicians treating the condition. Treatment depends on the etiology of the condition and generally requires thoughtful investi-gation, in several stages. The fi rst stage involves consideration of organic, nonfunc-tional causes, which can be identifi ed in about 15 % of patients [ 2 ]. The next stage looks for functional causes of pain. Rome III criteria divide such functional pains into proctalgia fugax, which is typifi ed by short-lasting episodes of severe pain, and levator ani syndrome (chronic idiopathic anal pain) in which the pain lasts for peri-ods of more than 20 min at a time or is permanent [ 3 ]. This chapter provides a structural, stepwise framework for the assessment and treatment of chronic anal pain to ensure that all diagnoses are considered. 244 11.1 Evaluation and Treatment of Common Nonfunctional Causes of Anal Pain 11.1.1 Diagnostic Algorithm When a patient presents with a suspected nonfunctional cause of chronic anal pain, a stepwise approach is essential to ensure that no possible diagnosis is overlooked (Fig. 11.1). The fi rst step, of course, is a through history, including known anorectal problems, radiation exposure, infl ammatory bowel disease, and anal trauma. After this, the next step is a detailed visual inspection and digital rectal exam. Many com-mon anorectal maladies can be identifi ed with this simple step. Visual inspection and digital rectal exam of the anorectum can exclude anal fi ssures, anal stricture, and other infections such as condyloma or herpes. In women, a bimanual exam can reveal gynecologic pathology, which may include endometriosis, vulvodynia, pro-lapse, or mesh erosion. Should initial physical exam fail to provide the diagnosis, ancillary tests may be performed. An offi ce test, anoscopy, can rule out anal cancer and distal rectal cancer or rectal stricture. A fl exible sigmoidoscopy or full colonoscopy can identify proxi-mal rectal cancer proctitis or a solitary rectal ulcer (Fig. 11.2). An MRI of the pelvis and rectum can reveal retrorectal pathology and cryptic perianal fi stulae. An MRI of the spine can exclude herniated disc and neurologic syndromes.