What are the symptoms of proctalgia? How is the diagnosis made?
There are two characteristic, benign syndromes with anal pain of uncertain etiology. We believe the pain is due to a spasm of the anal sphincter, in anal fugax, or a spasm of pelvic floor muscles such as the anal sphincter in limb anal sphincter syndrome (LAS). However, it still remains a topic for investigation.
Diagnosis is usually made on the basis of symptoms. Clinical examination, most of the time, shows nothing unusual. However, it is necessary to perform a full clinical assessment to rule out other conditions in the area. It is thought that emotional factors, sexual activity or fatigue may trigger an episode of pain.
How does proctalgia Fugax present?
At first, there is a cramping or spasm sensation in the rectum, about 5 to 10 cm above the anus, which gradually becomes more intense to the point of intolerance. After it peaks, it gradually subsides, usually lasting 20 minutes at a time. The pain can be induced suddenly and may wake the patient from sleep. It is often described as an indeterminate pain, high up in the rectum, or as a sharp pain that makes the patient feel as if someone is twisting a knife inside their rectum. The patient feels no pain at all between episodes.
Proctalgia fugax (PF) has no clinical findings and the diagnosis is made based on the characteristic symptoms and excluding other causes – conditions with similar pain. Abdominal palpation and rectal finger examination are the minimum assessment of anal pain – ideally Proctoscopy should be performed. Also, if appropriate, a gynecological or urinary examination may be done. Further examination by sigmoidoscopy or colonoscopy may be necessary in certain patients where a possible problem higher up in the colon is suspected.
How does anal sphincter syndrome present?
It is usually described as vague pain or a feeling of pressure in the lower part of the rectum that is often worsened by sitting or lying down, and relieved in an upright position. The pain tends to recur regularly and lasts from hours to days.
Posterior traction of the puborectalis muscle reveals tight (hypertonic) antecubital muscle and external anal sphincter and tenderness or pain in the area. Bathing with lukewarm water and massaging the area may improve the pain and characteristic discomfort.
What factors cause anal proctalgia?
Proctalgia is also often triggered by conditions such as: injury on the coccyx, pain low in the back, anal stretch marks, abscesses, distension due to lower bowel gas or prostate disorders. It may be associated with low-fiber diet and irritable bowel syndrome (IBS) or may be related to sedentary lifestyle. Anatomical deviations of the lumbosacral, coccyx and supporting structures are factors that predispose the anal muscle and anal sphincter to spasm.
What are the risk groups?
More than half of affected patients are aged 30-60 years, with a decreasing prevalence after age 45. Proctalgia has also been linked, with a number of other conditions which may have a causative role, for example vulvar nerve neuralgia. However, there is now a strong view that psychological factors, rather than physical-organic factors, are at the root of the problem.
Fugax Proctalgia (PF) is estimated to affect 8-18% of the population in the developed world, and Limb Anal Syndrome (LAS) about 6%. Levator ani syndrome (LAS) appears to affect women more than men. It is noted, however, that only 20-30% of sufferers will consult a doctor. Patients often delay in approaching the specialist doctor about their problem and this is due to embarrassment and fear of possible detection of some serious problem in the area.
Common symptoms with other conditions
There are some conditions that can cause similar pain (in the area), such as anal proctalgia. These are:
- Irritable bowel syndrome
- External hemorrhoidal thrombosis
- Ring stenosis (usually causes severe local pain associated with defecation) – should be visible on rectoscopy
- Chronic solitary rectal ulcer
- Carcinoma of the rectum
- Perilesional abscess or fistula. Pyogenic sweat adenitis.
- Proctitis (especially gonococcal or chlamydial infection)
- Crohn’s disease/ulcerative colitis
- Rectal foreign body
- Anal itching
- Diverticulosis
- Coccygodynia (neuralgic pain around the coccyx area)
- Rectal cysts – is a rare entity that can be difficult to detect without a high index of clinical suspicion (elective examination – pelvic CT scan)
- Testicular carcinoma
- Prostatitis
- Cystitis
- Alcock canal syndrome (neuralgia of the pudendal nerve due to entrapment, may cause a similar clinical picture to PF)
- Hereditary myopathy of the anal sphincter
- Obstruction of the internal iliac arteries