Constipation is one of the most common complaints expressed in medical consultation as well as to the GP to a specialist.
This symptom may impose looking for an organic underlying disease, but this need varies depending on the terrain and context.
In the absence of proven organicity, constipation becomes a symptom-disease, heterogeneous entity that meets many pathophysiological mechanisms. Functional constipation remains a mild illness, but its chronic nature often resistant to usual symptomatic treatments makes it difficult to support because of the fatigue caused by the patient’s repeated complaints, which can not be answered by a simple and effective therapeutic strategy.
The prevalence of constipation is between 15-20% of the population. It increases in the elderly. His female is constant in all epidemiological studies. In a recent study done in the city and involving over 800 patients, 70% female, mean age of 50 years and suffering from irritable bowel syndrome, constipation predominant in 37.2% of cases, diarrhea in 37 %, and a quarter had an alternation of the two.
The physiological definition of constipation is a slower transit determining excessive drying of the faeces with a dry weight greater than 22%. The clinical definition has been the subject of an international consensus: the Rome criteria.
For at least 12 weeks during the previous 12 months (not necessarily consecutive) presence of at least two of the following signs:
– Less than three exemptions per week;
– When at least 25% exemption, fragmented or hard stools;
– Sensation of incomplete evacuation;
– Of anorectal obstruction sensation;
– Digital maneuvers necessary to obtain the exemption;
– Absence of liquid stool or sufficient criterion for the diagnosis of irritable bowel diarrheal form.
Diagnostic criteria for irritable bowel syndrome:
For at least 12 weeks (not necessarily consecutive) during the previous year, the presence of abdominal pain or discomfort associated with at least two of the following signs:
– Pain relieved by defecation;
– And / or onset associated with a change in frequency of stool;
– And / or onset associated with a change in stool consistency.
Two mechanisms are recognized:
– Global slowdown transit: colonic inertia;
– Distal colonic obstruction: terminal constipation.
Disorders of the distal evacuation of rectosigmoid constitute the majority etiology of functional constipation.
The psychogenic factor is almost constant from childhood. Learning the continence of the child by the mother often determines educational faults causing an abnormal fixation on the issue of stool. More recently, it was stressed the importance of sexual abuse history (broadly defined) in the genesis of functional bowel disorders.
The examination is an essential preliminary, the word having constipation for each patient a different meaning to be evaluated. We must therefore patiently determine the number of bowel movements per week, consistency, appearance. This task is difficult because of a reluctance to this kind of examination of some patients, others conversely extending over a very obsessional description, but often interpretative.
Seniority disorders, possible triggers are to specify in particular: the medical and surgical history (see Box 1), any perineal trauma occurred during childbirth (episiotomy, difficult and long process), all treatments, former or current medications, especially laxatives often taken as self-medication before applying for medical management of symptoms.
Clinical examination aims to assess the state of the abdominal wall: tone, scar possible, disembowelment. The examination of the perineum is also an essential step in particular with full proctology examination. It is desirable to assess:
– Tone of the perineum;
– Tone of the anal sphincter at rest and during voluntary contraction and the thrust force;
– The existence of a prior rectocele (finger positioned hook forward allows charged on the push, the appearance of a more or less deep anterior cul-de-sac);
– The presence of stool in the rectum, useful to know if the patient does not feel a need to feel: it is generally witnessed a terminal type of constipation;
– The existence of a crack or a fistula inspection (in genupectorale position), often suspected problem by questioning the existence of pain during the emission of stool.
The existence of a prolapsed hemorrhoid is noteworthy, common consequence of untimely effort to get a seat.
The symptom-constipation is not in itself a formal indication to colonoscopy, especially when it occurs in younger patients. She discusses the slightest doubt, however, from the age of 45 to remove any ulterior motive before the establishment of a long-term treatment, especially when bleeding associated or a family history of polyps or bowel cancer.
Other specific explorations can specify constipation mechanism. Their indication remains limited to constipation rebels to usual treatments.
Transit time radiopaque markers:
The ingestion of radiopaque pellets measures the transit time segment by segment at the colic frame.
Several techniques are used, but their common point is the realization of a simple abdomen without preparation (ASP), usually 3-5 days after ingestion markers to define whether the constipation function under a colonic inertia (pellets stagnating in the right colon or the entire colon framework) or linked to a terminal barrier (stasis markers at the rectosigmoid).
The anorectal manometry is a useful examination to clarify the mechanisms of defecation disorders. It is not a first-line examination and only considers whether the usual symptomatic treatments do not allow good control of symptoms.
The review can appreciate the sphincter tone, the existence of anorectal inhibitory reflex: it is always kept in case of terminal type of constipation, but sometimes dulls. This is however not present in a rare disease – Hirschsprung’s disease – neonatal revelation in general, but whose recognition is sometimes later.
The review also includes a study of the rectal capacity that allows to recognize the acquired megarectum, linked to the terminal constipation.
Disorders of perirectal static can be specified by defecography which aims to visualize the movements of the rectum and anus during defecation. It can be integrated in a more comprehensive exploration: the colpocystodéfécographie with simultaneous opacification of both the bowel loops, bladder and vagina. Normally, during defecation, there is a rectal change position with opening of the anorectal angle and moderate lowering of the lower end of the rectum due to the intra-abdominal pressure.
The exam can effectively visualize the existence of a prior rectocele, the existence of a paradoxical contraction of the puborectalis (anismus) or the existence of a rectal intussusception (internal prolapse syndrome).
The main causes of constipation are presented in Box 1.
Box 1. Etiology of constipation
Lifestyle and dietary causes
Deficiency of dietary fiber
Causes of digestive colic origin
Non tumoral stenosis
Chronic intestinal pseudo-obstruction
Causes of anorectal digestive origin
Stenosis of varied etiology
Disorders of the rectal static
Metabolic endocrine causes
Neurological causes of central nervous system
Neurological causes peripheral nervous system
Dysautonomia secondary to diabetes, amyloidosis or a
Opioids (painkillers, drugs, antitussives)
This is the most common mechanism of constipation with an inability to empty the rectum despite thrust forces and sometimes digital maneuvers. There is often a lack of need or sensation of pelvic heaviness sensations or anorectal pain. The two diagnostic possibilities are either a anorectal dysfunction or disorder of the posterior perineal static.
The anismus asynergie or anorectal or abdominopelvic asynchrony is defined as a paradoxical contraction of the puborectalis muscle that does not relax during defecation despite the relaxation of the internal sphincter (objectified by the anorectal inhibitory reflex in manometry). In this case the anorectal angle remains closed since puborectale strap contracts instead of relaxing.
This can be seen during the DRE. When the patient pushes, one easily perceives the sensation of contraction (instead of loosening) of puborectal closing the anorectal angle.
The origin of this is likely asynergie psychogenic, but is sometimes seen in asymptomatic patients.
It can be improved by a specific rehabilitation (biofeedback).
Disorders of the posterior perineal static:
The rectocele is the most frequently observed abnormality. His frequent finding in asymptomatic patients must make careful interpretation. It is sometimes associated with rectal intussusception (or internal rectal prolapse) clinically suspected and objectified by defecography. This prolapse may determine the onset of an ulcer at the anterior wall of the rectum (the solitary ulcer syndrome of the rectum).
The congenital megacolon or Hirschsprung disease:
It is a congenital absence of ganglion cells in the parietal nervous plexus of a short segment of the general terminal colon. In most cases, only the rectum and the sigmoid sometimes is interested.
This disease is most often recognized the first days of life because of the absence of spontaneous evacuation of meconium. It can be recognized later in a constipated child from birth, small means (suppositories, enemas) for obtaining a transit. It can be recognized only during adolescence or adulthood, patients consulting for a major constipation which is notable is neonatal onset. The clinical element that draws attention is the fact that the rectum is empty, the above-aganglionic anal area to prevent the passage of stool.
The diagnosis is usually easy, anorectal manometry demonstrating the absence of anorectal inhibitory reflex. The diagnosis can then be confirmed by surgical biopsy of the anorectal junction which demonstrates the existence of a aganglionic area.
The treatment is surgical. Resection of the area with aganglionic coloanal anastomosis to replace the conventional intervention Duhamel.
The impaction is defined as a large mass of matter in the rectum or colon, the volume of hardness and prevent spontaneous emission.
The causes are many, especially LED in the elderly, often bedridden. The overall impaction seat in the rectum, but can be located above, in the sigmoid, or proximal colon. His frequent presentation in the form of a false diarrhea can delay diagnosis, and then prescribed anti-diarrhea treatments only worsen the picture.
DRE easily recognizes the problem, but if the fecal impaction is located above, is the ASP that will allow the diagnosis.
Its complications may be related to compression of the pelvic organs (urinary symptoms, pelvic pain or low rectal). A stercoral ulcer, linked to necrosis of the mucosa of compressive origin is sometimes observed after evacuation.
Treatment involves careful evacuation if necessary using digital maneuvers with the help of enemas or ingestion of polyethylene glycol (PEG) orally to try to soften in the rehydrating the fecal impaction. It is sometimes necessary to use general anesthesia for better anal dilatation (risk of vagal) for evacuation.
Colonic inertia primitive:
This is probably a visceral neuropathy, described especially in young women, and results in an isolated but very obstinate constipation, rebellious to all conventional medical treatments. It is much rarer than the terminal constipation. It gradually worsens with emission of a saddle every 3-4 weeks. He joins in abdominal pain, bloating, nausea, general weakness.
Diagnosis is made using the transit of radiopaque markers that show an overall slowing of colonic transit at the frame.
It is reasonable to perform a colonoscopy to remove any organicity. Anorectal manometry to confirm the normality of defecation mechanisms (presence of anorectal inhibitory reflex) and the absence of megarectum.
After eliminating the general causes of colonic inertia (hypothyroidism, neurological disease, laxatives disease), it is sometimes necessary to consider (a rarity), total colectomy with anastomosis ileorectal.
This exceptional decision must nevertheless be taken in a specialized environment because of its severity.
This is a secondary table to prolonged consumption of large amounts of laxatives favored by frequent self-medication and OTC laxatives herbal teas and many pharmacies.
This is a rare, almost exclusively female. Laxatives is often hidden by the patient, and the only way to authenticate is sometimes looking for laxatives in stool or urine. Anthraquinone and phenolphthalein derivatives are most commonly involved. Diarrhea is common but inconsistent, often abundant secretory type of water sometimes losing enteropathy. There is a potassium leak often associated with metabolic acidosis, hypocalcemia and hypomagnesemia.
When colonoscopy is performed, attention must be drawn to a melanose while the patient consults for diarrhea.
Treatment is difficult, the patient recognized the doctor often beyond it and then the disease continues to evolve.
The purpose of these drugs is to obtain a discharge of a molded seat and hydrated.
This is sometimes difficult to achieve and drugs sometimes determine after a phase of resistance diarrheal debacle.
Several families of mild laxatives can be used without difficulty even in the long term: dietary fiber, mucilage or bulk laxatives, oily laxatives, osmotic laxatives. Other families more irritants are frequently used, effective but dangerous if prolonged use in disrupting the absorption and intestinal secretion.
Dietary fibers have an interesting activity, their water retention capacity to improve the hydration and stool volume. A moderate increase in the daily ration in fiber, often too low in the Western diet is sometimes suffi cient to improve moderate constipation.
Mucilages act in the same manner, gum extract (karaya, karaya) or seed (psyllium, Isphagula). The common disadvantage of fiber or mucilage is the frequent appearance, especially early in treatment, significant bloating and flatulence which may limit its use. The gradual introduction of treatment sometimes improves tolerance.
Based on paraffin oil, they facilitate the increase in fecal bolus and reduce the absorption of water in the colon.
Their effectiveness is medium and high dose often responsible oil seeps at the anus poorly tolerated by patients.
There are three classes:
– The oldest, saline laxatives (eg magnesium sulfate), are being abandoned in favor of two other classes: synthetic disaccharides and PEG;
– Synthetic disaccharide (lactulose or lactitol) are not degraded sugars in the small intestine and therefore not absorbed; They thus exert an osmotic effect in the colon where they will be fermented, which is a gas production source sometimes poorly tolerated by patients;
– PEG of high molecular weight polymer and thus non-absorbable, there was introduced a few years ago, first of all for the preparation for colonoscopy (3 to 4 liters). Their smaller dose efficacy in constipation has been proven by clinical studies. PEGs are a good alternative to synthetic disaccharide; they have a water retention capacity greater than laxatives fermentable, at equal osmotic load, and do not induce gas production.
Irritants laxatives are often taken as self-medication because they are counter in pharmacies in tablets or as teas.One distinguishes derivatives phenolphthalein
– Major laxative disturbing the absorption of water and electrolytes in the small bowel and colon and levels anthraquinone (derived from senna, Buckthorn and aloe vera). These laxatives are partially absorbed and can be found both in feces than in urine.
Bisacodyl himself is poorly absorbed and has a direct effect on the secretory lining of the colon.
This family of drugs may be occasionally useful in the case of constipation difficult, but their prolonged use should be avoided, to the extreme can determine a laxative sick with hypokalemia, hypomagnesemia, dehydration. Prolonged use of anthraquinone determines a colonoscopy colonic melanosis easy to recognize.
In the terminal type of constipation, they can be an interesting extra. The glycerin suppositories have péristaltogène effect.
Gassing of suppositories or microenemas exonérateur can trigger reflex.
This is a behavioral therapy indicated if anismus or anorectal inhibitory reflex blunt, under the type of terminal constipation. Efficiency is variously estimated, but could improve the table in about 50% of cases.
Constipation being a motor component to disease, the use of prokinetic is logical. Few new products have come up in recent years. Some work has recently suggested that the serotonin metabolism disturbances may be involved.
Tests utilizing 5-HT4 agonists serotonin receptors (tegaserod) have demonstrated efficacy in the treatment of irritable bowel syndrome with constipation-predominant.
The product marketed in the United States and Switzerland, do not always is in France. It appears to improve the transit but not abdominal pain. Some cases of ischemic colitis have been reported with this product.
Prostigmine or its derivatives (Mestinon®) can sometimes be attempted in case of colonic inertia, after verifying the absence of colonic obstruction.
In the terminal type of constipation, disorders of the pelvic floor can sometimes benefit from a surgical procedure to restore the defecation function. The most frequent indications concern large anterior rectal prolapse and rectocele, internal or externalized which are sometimes complicated of a solitary ulcer syndrome of the rectum.
The total colectomy with ileorectal or anal anastomosis has sometimes been proposed but this is an exceptional solution to an approach that in case of major colonic inertia, usually in young women, and after excluding all other conditions which may determine severe constipation. This indication must be done by specialized environment.