Proctalgia fugax

INTRODUCTION — Proctalgia fugax is a functional anorectal disorder characterized by severe, intermittent episodes of rectal pain that are self-limited. The diagnosis of proctalgia fugax requires exclusion of other causes of rectal or anal pain.

This topic will review the epidemiology, clinical manifestations, diagnosis, and management of proctalgia fugax. Other functional gastrointestinal disorders and disorders that affect the anus or rectum are discussed separately. (See "Clinical manifestations and diagnosis of irritable bowel syndrome in adults" and "Perianal and perirectal abscess" and "Anal fissure: Clinical manifestations, diagnosis, prevention" and "Hemorrhoids: Clinical manifestations and diagnosis" and "Perianal Crohn disease" and "Clinical manifestations, diagnosis, and prognosis of ulcerative colitis in adults" and "Clinical presentation, diagnosis, and staging of colorectal cancer" and "Clinical features and staging of anal cancer".)

EPIDEMIOLOGY — Proctalgia fugax is estimated to affect 4 to 18 percent of the general population [1-5]. However, only 17 to 20 percent of patients report their symptoms to a physician. Although proctalgia has been reported in adult patients ranging from 18 to 87 years of age, it usually affects individuals between 30 and 60 years of age [6-9]. Proctalgia fugax is more common among female patients as compared with males [3,8].

PATHOPHYSIOLOGY — The sporadic and transient nature of proctalgia fugax has limited efforts to determine the underlying pathophysiologic basis, but spasm of the anal sphincter, pudendal nerve compression, and neuropathy have been implicated.

Muscle spasm/hypertrophy — Patients with proctalgia fugax have normal anorectal pressures when asymptomatic, but exhibit motor abnormalities of the anal smooth muscle during an acute attack [7,10]. In one study that included 18 patients with proctalgia fugax, anorectal manometry demonstrated slightly increased resting anal pressures, but no differences in squeeze pressure, sphincter relaxation, rectal compliance, or internal and external anal sphincter thickness [7]. In two patients, anorectal manometry provoked symptoms of proctalgia fugax. Furthermore, increasing duration of pain was associated with an increase in anal resting tone and slow wave amplitude. A rare autosomal dominant inherited myopathy of the internal anal sphincter has also been associated with proctalgia fugax [11-13].

Nerve compression — Pudendal nerve compression or neuralgia has been implicated in the pathogenesis of proctalgia fugax [14,15]. In a study of 68 patients with a history of proctalgia fugax, 55 patients (81 percent) had tenderness along the pudendal nerve during digital rectal examination [14]. The location, character, and degree of pain elicited by digital examination were similar to the pain experienced during spontaneous paroxysms of proctalgia fugax. Of the 20 patients with severe symptoms who were treated with a nerve block, there was resolution of symptoms in 13 patients (65 percent) and a reduction in symptoms in 5 patients (25 percent) at eight weeks.

Other — Other factors that may contribute to the symptoms of proctalgia fugax include visceral hypersensitivity, anxiety, and an association with other functional bowel disorders [5,16].

CLINICAL MANIFESTATIONS — Patients with proctalgia fugax have recurrent attacks of severe anorectal pain that can occur during the day or night. Each episode may last from a few seconds to minutes, but the duration does not exceed 30 minutes [17,18]. Patients are asymptomatic between episodes [19]. The attacks are usually infrequent, occurring less than five times per year in approximately one-half of patients, but wide ranges have been reported (1 to 180 attacks per year) [6,20]. Most episodes are not associated with an obvious trigger, although some studies have suggested that some attacks may be related to a precipitating factor such as stress, defecation, menstruation, or constipation [6,17,21].

DIAGNOSIS — According to the Rome IV criteria, a diagnosis of proctalgia fugax requires all of the following criteria to be fulfilled for the past three months, with symptom onset at least six months prior to diagnosis [18]:

●Recurrent episodes of pain localized to the rectum and unrelated to defecation

●Episodes last from seconds to minutes, with a maximum duration of 30 minutes

●Absence of anorectal pain between episodes

The diagnosis also requires the exclusion of anorectal and pelvic pathology (eg, inflammatory bowel disease, intramuscular abscess or fissure, thrombosed hemorrhoid, coccydynia, and major structural alterations of the pelvic floor). (See 'Differential diagnosis' below and 'Evaluation' below.)

Evaluation — The diagnosis of proctalgia fugax should be suspected in patients with recurrent, episodic pain in the anus and lower rectum. Evaluation of a patient with suspected proctalgia fugax serves to exclude other causes of rectal pain and establish the diagnosis of proctalgia fugax. The diagnostic evaluation consists of:

●A digital rectal examination with inspection of the perianal skin for fissures, ulcers, external hemorrhoids, or prolapsed internal hemorrhoids; and palpation for thrombosed internal hemorrhoids and tenderness to palpation of the coccyx suggestive of coccydynia. In male patients, a prostate examination should be performed to evaluate for prostate hypertrophy, tenderness, edema, and nodularity that suggests the presence of chronic prostatitis. (See "Coccydynia (coccygodynia)", section on 'Diagnosis' and "Anal fissure: Clinical manifestations, diagnosis, prevention", section on 'Physical examination'.)

●A pelvic examination in female patients to rule out pelvic inflammatory disease. (See "Pelvic inflammatory disease: Clinical manifestations and diagnosis", section on 'Diagnosis'.)

●Laboratory studies including complete blood count, electrolytes, and markers of inflammation including a C-reactive protein (CRP). These laboratory studies are normal in patients with proctalgia fugax and, if elevated, are suggestive of another etiology of rectal pain.

●Colonoscopy or flexible sigmoidoscopy to rule out other causes of rectal pain (eg, inflammatory bowel disease, hemorrhoids).

●In patients who are refractory to initial management and in patients with fever or leukocytosis, we perform an endoanal ultrasound or magnetic resonance imaging of the abdomen and pelvis. In patients with concurrent constipation, we perform an anorectal manometry to rule out pelvic floor dysfunction. (See "Etiology and evaluation of chronic constipation in adults", section on 'Defecation disorder' and "Etiology and evaluation of chronic constipation in adults", section on 'Assessment for a defecation disorder'.)

DIFFERENTIAL DIAGNOSIS — Anorectal pain may be caused by hemorrhoids, anorectal abscesses, anal fissures, rectocele, anorectal carcinoma, inflammatory bowel disease, pelvic inflammatory disease, chronic benign prostatitis, and coccydynia. These conditions can be excluded by the evaluation, as discussed above. (See 'Evaluation' above and "Hemorrhoids: Clinical manifestations and diagnosis", section on 'Clinical manifestations' and "Anal fissure: Clinical manifestations, diagnosis, prevention", section on 'Physical examination' and "Pelvic inflammatory disease: Clinical manifestations and diagnosis", section on 'Diagnosis' and "Coccydynia (coccygodynia)", section on 'Diagnosis' and "Perianal and perirectal abscess", section on 'Clinical manifestations'.)

●Levator ani syndrome – Patients with chronic proctalgia (also referred to as levator spasm, puborectalis syndrome, piriformis syndrome, or pelvic tension myalgia) describe a vague, dull ache or pressure sensation high in the rectum, often worse with sitting than with standing or lying down.

According to the Rome IV criteria, in order to diagnose levator ani syndrome, patients have to meet all of the following criteria for the past three months, with symptom onset at least six months prior to diagnosis [18] :

•Chronic or recurrent rectal pain or aching

•Episodes last at least 30 minutes

•Exclusion of other causes of rectal pain

•Tenderness is elicited during posterior traction of the puborectalis

Patients who meet all the criteria for levator ani syndrome with the exception of tenderness during posterior traction of the puborectalis, are classified by Rome IV criteria as having unspecified functional anorectal pain.

●Coccydynia – Patients complain of pain in the tailbone on sitting, especially when leaning back, and pain on rising and with prolonged standing. Other pelvic floor symptoms such as painful defecation may be reported. The pain may radiate to the floor of the pelvis. The diagnosis of coccydynia is established by rectal examination that demonstrates tenderness and pain on movement of the coccyx, while adjacent structures are not tender. The clinical manifestations, diagnosis, and management of coccydynia are described in detail, separately. (See "Coccydynia (coccygodynia)", section on 'Diagnosis'.)

MANAGEMENT — For most patients, symptomatic episodes are brief and infrequent and require no specific treatment [4,17]. Only a small percentage of patients have more frequent and troubling symptoms. However, there are limited data to guide management in patients with proctalgia fugax [22].

Initial treatment — In most patients with mild and infrequent symptoms, we suggest reassurance and explanation [5,10]. The episodes of pain are typically brief, and prevention is not possible.

For patients who experience severe or frequent symptoms, sitz baths and treatment with topical antispasmodics may be helpful.

Topical antispasmodics — Topical therapy with nitroglycerin (0.2 percent) or topical diltiazem gel (2 percent) has been used to treat proctalgia fugax at the onset of symptoms by decreasing internal anal sphincter pressure [5,23]. We have found that topical diltiazem gel (2 percent) can also be helpful and is often better tolerated than topical nitroglycerin. The major side effect of topical nitroglycerin is headache. The use of a topical calcium channel blocker for proctalgia fugax is supported by indirect data in patients with anal pain after hemorrhoidectomy [24].

Subsequent therapy and evaluation — In patients with severe or frequent symptoms who fail to respond to topical treatment, we perform additional evaluation with a rectal endoscopic ultrasound or magnetic resonance imaging of the abdomen and pelvis, if not performed as part of the initial evaluation [25]. If no alternative etiology is found, we suggest biofeedback therapy for patients with severe or frequent symptoms who do not respond to initial therapy.

Biofeedback therapy — Biofeedback therapy is noninvasive and has been used to treat functional anorectal pain syndromes, including proctalgia fugax. In one study, the clinical response to biofeedback was greatest in patients who reported difficulty with defecation [17].

Therapies of uncertain benefit — For patients with proctalgia fugax, we do not typically use inhaled beta-2-adrenergic agonists [26] or interventions such as botulinum toxin injection and pudendal nerve block [14,27] because randomized trials have not demonstrated their efficacy [28].

SUMMARY AND RECOMMENDATIONS

●Proctalgia fugax is a functional anorectal disorder characterized by severe, intermittent episodes of rectal pain that are self-limited. (See 'Introduction' above.)

●Proctalgia fugax affects 4 to 18 percent of the general population. The incidence of proctalgia fugax is higher in females as compared with males. Although proctalgia has been reported in adult patients ranging from 18 to 87 years of age, it usually affects individuals between 30 and 60 years of age. Spasm of the anal sphincter, pudendal nerve compression, and neuropathy have been implicated in the pathogenesis of proctalgia fugax. (See 'Epidemiology' above and 'Pathophysiology' above.)

●Patients with proctalgia fugax have recurrent attacks of severe anorectal pain that may last from a few seconds to minutes, but the duration does not exceed 30 minutes. Patients are asymptomatic between episodes. The attacks are usually infrequent, occurring less than five times per year in approximately one-half of patients. Most episodes are not associated with an obvious trigger. (See 'Clinical manifestations' above.)

●The Rome IV criteria for the diagnosis of proctalgia fugax require the presence of all of the following criteria for the past three months, with symptom onset at least six months prior to diagnosis: recurrent episodes of pain localized to the rectum, episodes lasting from seconds to minutes (with a maximum duration of 30 minutes), and the absence of anorectal pain between episodes. The Rome IV criteria also require the exclusion of other causes of rectal pain and major structural alterations of the pelvic floor. (See 'Diagnosis' above.)

●Evaluation of a patient with suspected proctalgia fugax serves to exclude other causes of rectal pain and establish the diagnosis of proctalgia fugax. We perform a digital rectal examination, examination of the prostate in males, and a pelvic examination in females. In addition, we perform routine laboratory studies and endoscopic evaluation with a colonoscopy or flexible sigmoidoscopy. In patients who are refractory to initial management and in patients with fever or leukocytosis, we perform an endoanal ultrasound or magnetic resonance imaging of the abdomen and pelvis. (See 'Differential diagnosis' above and 'Evaluation' above.)

●Most patients have mild and intermittent symptoms and require no specific treatment other than reassurance and explanation of the disorder. For patients with severe or frequent symptoms, we suggest topical treatment with nitroglycerin to treat an acute attack (Grade 2C). For patients who do not respond to topical treatment, we suggest biofeedback therapy (Grade 2C). (See 'Management' above.)