Overview.
Functional anorectal pain is anorectal pain that lacks evidence of organic disease and is an uncommon form of functional anorectal disease. Clinically, it can present as a frequent vague dull pain that lasts for a long period of time, or as an episodic sharp pain that lasts only a few seconds to a few minutes. It is most common in women, and is more common in people aged 30 to 60 years.
Etiology
The etiology and pathophysiologic mechanism are not clear, and may be related to the following aspects.
1. Abnormal pelvic floor muscle movement
Excessive spasmodic contraction of the anorectal muscles is the main cause, which may also be related to pelvic floor dysfunction.
2. Mental and psychological factors
Patients are often accompanied by paranoia, anxiety, depression, dysthymia and so on.
3. Mechanical factors
Long-term excessive physical labor, sedentary and so on.
4. Neurological factors
Stimulation of the nerves in the pubic area can cause spasmodic anorectal pain, and the pain can be radiated to the area innervated by the nerves in the pubic area.
5. Hereditary factors
People with a family history of functional anorectal pain have a greater chance of developing the disease.
Symptoms
According to the duration, frequency and characteristics of the pain, it is categorized into chronic anorectal pain and spasmodic anorectal pain. The former includes the anorectal raphe syndrome and non-specific functional anorectal pain.
1. Chronic anorectal pain
The performance of the anorectal area of fuzzy dull pain, usually pain for a long time (more than 20 minutes), or presenting increased rectal pressure sensation, sitting position than the standing position or lying down, lasting from hours to days, with the morning symptoms of light, aggravated by midday, the pattern of symptoms disappear at night. According to pulling the puborectalis muscle with or without pain is divided into the anorectal raphe syndrome and non-specific anorectal pain, the former appear pain, the latter no pain.
2. Spasmodic anorectal pain
The manifestation of recurrent spasmodic sharp pain confined to the anus or lower rectum, stressful events or anxiety is often the trigger. Most of the attacks at night, affecting sleep, a short period of time (a few seconds to a few minutes) can be relieved on their own, without leaving other discomfort.
Examination
1. Physical examination
Chronic anorectal pain can be found on rectal examination with excessive contraction of the anorectal muscles and tenderness on palpation of the pelvic floor.
2.Laboratory examination
(1) Blood routine: white blood cell count is mostly normal.
(2) Stool routine: attention should be paid to the examination of fecal character, red blood cells and white blood cells, parasites (eggs), fat droplets, etc., in order to determine the presence of gastrointestinal bleeding, bacterial or parasitic infections, and dyspepsia and other diseases.
3.Imaging examination
Through anorectoscopy, sigmoidoscopy, to determine whether there is organic lesions, such as ischemia, inflammation, abscess, anal fissure, etc. found to indicate the presence of organic lesions.
Diagnosis
No recent history of gastrointestinal inflammation, prostatitis, anal fissure, hemorrhoids, etc. Clinical manifestations are important diagnostic basis, chronic anorectal pain is a persistent vague dull pain, episodes last 20 minutes or more; spasmodic anorectal pain manifested as short episodes of sharp pain, to exclude other causes of rectal pain, the white blood cell count is usually within the normal range, no abnormal performance of the routine stool, combined with the imaging examination of the diagnosis of no abnormal performance can be made.
Differential diagnosis
1. Tailbone pain
Mostly seen in women and old and frail patients, mostly originated from acute trauma, poor sitting posture or chronic injury caused by sedentary, sacrococcygeal arthritis. Tenderness at the coccyx, aggravated by sitting position, can be relieved by massaging the coccyx.
2. Other perianal or rectal organic lesions
Such as inflammatory bowel disease, cryptitis, intermuscular abscess, anal fissure, hemorrhoids, prostatitis, women’s chronic pelvic pain and other diseases, through rectal fingerprinting, anorectoscopy, pelvic imaging can be identified.
Treatment
Non-surgical treatment is the mainstay, and symptoms can be effectively relieved by decreasing the tension of the transverse striated muscles of the pelvic floor. Spasmodic anorectal pain often comes on suddenly and lasts for a short period of time, after which it can be completely relieved, so most of them only need psychological treatment.
1. General treatment
Psychological counseling, correction of sedentary habits, warm water sitz baths, relief of fatigue, etc.
2. Medication
(1) Oral medication: nifedipine and diltiazem are mainly used for functional anorectal pain caused by hereditary internal sphincter myopathy. By antagonizing calcium ions, they can relieve spasm of the anorectal muscles to reduce pain, and it should be noted that patients with severe hypotension cannot apply these two medications.
(2) Topical medication: when treating spasmodic anorectal pain with topical application of 0.3% nitroglycerin ointment, the patient’s pain can be relieved, and serious adverse reactions rarely occur.
(3) Others: Inhaled salbutamol can significantly shorten the duration of severe pain, especially for those patients whose pain lasts longer than 20 minutes, the effect is more obvious; can also be used to treat spasmodic anorectal pain with intra-anal sphincter injections of botulinum toxin A. Botulinum toxin A can block the release of acetylcholine, which prevents paroxysmal sphincter overmovement, thus relieving the pain. .
3. Biofeedback therapy
Through repeated positive and negative attempts of training, the coordination of pelvic floor muscles and diastolic perception can be improved. This treatment method is effective for some patients, and the success of biofeedback has a certain relationship with the patient’s willingness to accept the whole treatment process.
4.Nerve block treatment
Ultrasound-guided local injection of anesthetics and/or ethanol to seal the corresponding pelvic nerves (e.g., pubic nerves) is effective in the short term, but not in the long term.
Prognosis
Timely and appropriate treatment measures can effectively relieve the symptoms. The disease is characterized by recurrent episodes and cannot be completely cured at present, but the disease can be asymptomatic during the period of non-episodes.
Nursing care
Rest should be paid attention to, avoid excessive fatigue, accept health education, maintain a positive and optimistic attitude, for spasmodic anorectal pain patients can take oral diltiazem to prevent attacks.