Neurogenic bowel dysfunction

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Neurogenic bowel dysfunction
Illu colorectal anatomy.jpg
The image shows the 4 parts of the colon (ascending, transverse, descending and sigmoid) and the rectum. Faeces are transported along and stored in the rectum before excretion.
Specialty Gastroenterology

Neurogenic bowel dysfunction (NBD) is the inability to control defecation due to a deterioration of or injury to the nervous system, resulting in faecal incontinence or constipation. [1] It is common in people with spinal cord injury (SCI), multiple sclerosis (MS) or spina bifida. [2]

Contents

The gastrointestinal tract has a complex control that relies on coordinated interaction between muscular contractions and neuronal impulses. [3] Faecal incontinence or constipation occurs when there is a problem with the normal bowel functioning; this could be for a variety of reasons. The normal defecation pathway involves contractions of the colon in order to help mix the contents, absorb water and propel the contents along the intestine. This results in the faeces moving from the colon to the rectum. [4] The presence of stool in the rectum causes a reflexive relaxation of the internal anal sphincter, so the contents of the rectum can move in to the anal canal. This causes the conscious feeling of the need to defecate. At a suitable time our brain can send signals causing the external anal sphincter and puborectalis muscles to relax as these are under voluntary control and this allows defecation to take place. [4] [5]

Spinal cord injury and other neurological problems mostly affect the lower GI tract leading to symptoms of incontinence or constipation. However, the upper GI tract may also be affected and patients with neurogenic bowel often present with multiple symptoms. [6] [7] Research shows there is a high prevalence of upper abdominal complaints, for example a study showed that approximately 22% of SCI patients reported feeling bloated [6] [8] and about 31% of SCI patients experienced abdominal distension. [6] [9]

Signs and symptoms

In neurogenic bowel dysfunction there may be fecal incontinence, constipation, or both combined. [10] One type of constipation which may occur in people with neurogenic bowel dysfunction is obstructed defecation. [10]

Neurogenic bowel dysfunction can have an impact on a person's life as it often leads to difficulties with self-esteem, personal relationships, social life and can also reduce a person's independence. [5] There is also evidence from studies showing that faecal incontinence can increase the risk of depression and anxiety. [11]

Causes

Different neurological disorders affect the gastrointestinal tract in different ways:

Spinal cord injury

Bowel dysfunction caused by a spinal cord injury will vary greatly depending on the severity and level of the spinal cord lesion. In complete spinal cord injury both sensory and motor functions are completely lost below the level of the lesion so there is a loss of voluntary control and loss of sensation of the need to defecate. [12] An incomplete spinal cord injury is one where there may still be some sensation or motor function below the level of the lesion. [12]

Colorectal dysfunction due to spinal cord injury can be classified in to two types: an  upper motor neuron lesion or lower motor neuron lesion. Problems with the upper motor neuron in a neurogenic bowel results in a hypertonic and spastic bowel because the defecation reflex centre, which causes the involuntary contraction of muscles of the rectum and anus, remains intact. [5] However, the nerve damage results in disruption to the nerve signals and therefore there is an inability to relax the anal sphincters and defecate, often leading to constipation. [5] An upper motor neuron lesion is one that is above the conus medullaris of the spinal cord and therefore above the vertebral level T12. [13] On the other hand, a lower motor neuron lesion can cause areflexia and a flaccid external anal sphincter so most commonly leading to incontinence. Lower motor neuron lesions are damage to nerves that are at the level of or below the conus medullaris and below vertebral level T12. However, both upper and lower motor neuron disorders can lead to constipation and/ or incontinence. [14] [13]

Spina bifida

Patients with spina bifida have a neural tube that has failed to completely form. This is most commonly in the lower back area in the region of the conus medullaris or cauda equina. It, therefore, affects the bowel similarly to a spinal cord injury affecting the lower motor neuron, resulting in a flaccid unreactive rectal wall and means the anal sphincter does not contract and close therefore leading to stool leakage. [12] Most patients with spina bifida also have hydrocephalus this can result in intellectual deficits so can contribute to faecal incontinence. [5]

Multiple sclerosis

There are a variety of symptoms associated with this condition that are all caused by a loss of myelin, the insulating layer surrounding the neurones. This means the nerve signals are interrupted and slower which will then cause muscle contractions to be fewer and irregular resulting in an increased colon transit time. [12] The faeces being in the colon for a longer time will mean that more water is absorbed leading to harder stools and therefore increasing the symptoms of constipation. This neurological problem can also lead to reduced sensation of rectal filling and weakness of the anal sphincter because of weak muscular contraction so can cause stool leakage. [12] In patients with multiple sclerosis constipation and faecal incontinence often coexist and they can be acute, chronic or intermittent due to the fluctuating pattern of MS. [5]

Brain lesion

Damage to the defecation centre within the medulla oblongata of the brain can lead to bowel dysfunction. A stroke or acquired brain injury may lead to damage to this centre in the brain. Damage to the defecation centre can lead to a loss of coordination between rectal and anal contractions and also a loss of awareness of the need to defecate. [12]

Parkinson's disease

This condition differs as it affects both the extrinsic and enteric nervous systems due to the decreased dopamine levels in both. This results in less smooth muscle contraction of the colon, increasing the colon transit time. [12] The reduced dopamine levels also causes dystonia of the striated muscles of the pelvic floor and external anal sphincter. This explains how Parkinson's disease can lead to constipation. [14]

Diabetes mellitus

Twenty percent of people with diabetes mellitus experience faecal incontinence due to irreversible autonomic neuropathy. This is due to the high blood glucose levels over time damaging the nerves, which can lead to impaired rectal sensation. [12]

Mechanism

There are different types of neurons involved in innervating the lower GI tract these include: the enteric nervous system; located within the wall of the gut, and the extrinsic nervous system; comprising sympathetic and parasympathetic innervation. [3] The enteric nervous system directly controls the gut motility, whereas the extrinsic nerve pathways influence gut contractility indirectly through modifying this enteric innervation. [3] In almost all cases of neurogenic bowel dysfunction it is the extrinsic nervous supply affected and the enteric nervous supply remains intact. The only exception is Parkinson's disease, as this can affect both the enteric and extrinsic innervation. [12]

Defecation involves conscious and subconscious processes, when the extrinsic nervous system is damaged either of these can be affected. Conscious processes are controlled by the somatic nervous system, these are voluntary movements for example the contraction of the striated muscle of the external anal sphincter is instructed to do so by the brain, which sends signals along the nerves innervating this muscle. [15] [16] Subconscious processes are controlled by the autonomic nervous system; these are involuntary movements such as contraction of the smooth muscle of the internal anal sphincter or the colon. The autonomic nervous system also provides sensory information; this could be about the level of distension within the colon or rectum. [15] [16]

Diagnosis

This image shows constipation in a young child as seen on X-ray. Constipation1.JPG
This image shows constipation in a young child as seen on X-ray.

In order to correctly manage neurogenic bowel dysfunction it is important to accurately diagnose it. This can be done by a variety of methods, the most commonly used would be taking a clinical history and carrying out physical examinations which may include: abdominal, neurological and rectal examinations. [17] Patients may use the Bristol Stool Chart to help them describe and characterise the morphological features of their stool, this is useful as it gives an indication of the transit time. [18] An objective method used to evaluate the motility of the colon and help with diagnosis is the colon transit time. [19] Another helpful test to diagnose this condition may be an abdominal X-ray as this can show the distribution of the faeces and show any abnormalities with the colon, for example a megacolon. [14] Methods used for diagnosis may vary depending on if the patient is ncontinent or constipated.[ citation needed ]

Management

Management and treatment for neurogenic bowel dysfunction depends on symptoms and biomedical diagnosis for cause of the condition. [14] General practitioners will often refer patients to gastroenterologist to effectively manage the neurogenic bowel dysfunction. Research has been conducted on a variety of therapy and treatments for neurogenic bowel dysfunction including: diet modification, laxatives, magnetic and electrical stimulation, manual evacuation of feces and abdominal massage, enemas, and pulsed irrigation evacuation (PIE). [15] [20] [21] Efficacy studies for pulsed irrigation evacuation with PIEMED demonstrated favorable results, removing stool of 98% of patients who used it for ineffective bowel routine, symptomatic impaction, or asymptomatic impaction. [20] In the most severe of cases of neurogenic bowel dysfunction induced fecal impaction, surgical interventions like colostomy are used to disrupt the dense mass of stool. [22] [23]

See also

Related Research Articles

<span class="mw-page-title-main">Defecation</span> Expulsion of feces from the digestive tract

Defecation follows digestion, and is a necessary process by which organisms eliminate a solid, semisolid, or liquid waste material known as feces from the digestive tract via the anus or cloaca. The act has a variety of names ranging from the common, like pooping or crapping, to the technical, e.g. bowel movement, to the obscene (shitting), to the euphemistic, to the juvenile. The topic, usually avoided in polite company, can become the basis for some potty humor.

<span class="mw-page-title-main">Constipation</span> Infrequent or difficult bowel movements

Constipation is a bowel dysfunction that makes bowel movements infrequent or hard to pass. The stool is often hard and dry. Other symptoms may include abdominal pain, bloating, and feeling as if one has not completely passed the bowel movement. Complications from constipation may include hemorrhoids, anal fissure or fecal impaction. The normal frequency of bowel movements in adults is between three per day and three per week. Babies often have three to four bowel movements per day while young children typically have two to three per day.

<span class="mw-page-title-main">Fecal incontinence</span> Inability to refrain from defecation

Fecal incontinence (FI), or in some forms, encopresis, is a lack of control over defecation, leading to involuntary loss of bowel contents — including flatus (gas), liquid stool elements and mucus, or solid feces. FI is a sign or a symptom, not a diagnosis. Incontinence can result from different causes and might occur with either constipation or diarrhea. Continence is maintained by several interrelated factors, including the anal sampling mechanism, and incontinence usually results from a deficiency of multiple mechanisms. The most common causes are thought to be immediate or delayed damage from childbirth, complications from prior anorectal surgery, altered bowel habits. An estimated 2.2% of community-dwelling adults are affected. However, reported prevalence figures vary. A prevalence of 8.39% among non-institutionalized U.S adults between 2005 and 2010 has been reported, and among institutionalized elders figures come close to 50%.

<span class="mw-page-title-main">Rectal prolapse</span> Protrusion of the walls of the rectum outside the body

A rectal prolapse occurs when walls of the rectum have prolapsed to such a degree that they protrude out of the anus and are visible outside the body. However, most researchers agree that there are 3 to 5 different types of rectal prolapse, depending on whether the prolapsed section is visible externally, and whether the full or only partial thickness of the rectal wall is involved.

<span class="mw-page-title-main">Onuf's nucleus</span> Group of neurons

Onuf's nucleus is a distinct group of neurons located in the ventral part of the anterior horn of the sacral region of the human spinal cord involved in the maintenance of micturition and defecatory continence, as well as muscular contraction during orgasm. It contains motor neurons, and is the origin of the pudendal nerve. The sacral region of the spinal cord is the fourth segment of vertebrae in the spinal cord which consists of the vertebrae 26-30. While working in New York City in 1899, Bronislaw Onuf-Onufrowicz discovered this group of unique cells and originally identified it as “Group X.” “Group X” was considered distinct by Onufrowicz because the cells were different in size from the surrounding neurons in the anterolateral group, suggesting that they were independent.

Functional constipation, also known as chronic idiopathic constipation (CIC), is defined by less than three bowel movements per week, hard stools, severe straining, the sensation of anorectal blockage, the feeling of incomplete evacuation, and the need for manual maneuvers during feces, without organic abnormalities. Many illnesses, including endocrine, metabolic, neurological, mental, and gastrointestinal obstructions, can cause constipation as a secondary symptom. When there is no such cause, functional constipation is diagnosed.

<span class="mw-page-title-main">Fecal impaction</span> Solid buildup of feces in the rectum due to chronic constipation

A fecal impaction or an impacted bowel is a solid, immobile bulk of feces that can develop in the rectum as a result of chronic constipation. Fecal impaction is a common result of neurogenic bowel dysfunction and causes immense discomfort and pain. Its treatment includes laxatives, enemas, and pulsed irrigation evacuation (PIE) as well as digital removal. It is not a condition that resolves without direct treatment.

<span class="mw-page-title-main">Internal anal sphincter</span> Ring of smooth muscle that surrounds part of the anal canal

The internal anal sphincter, IAS, or sphincter ani internus is a ring of smooth muscle that surrounds about 2.5–4.0 cm of the anal canal. It is about 5 mm thick, and is formed by an aggregation of the smooth (involuntary) circular muscle fibers of the rectum. It terminates distally about 6 mm from the anal orifice.

<span class="mw-page-title-main">Neurogenic bladder dysfunction</span> Bladder disorder due to disease or injury of the nervous system

Neurogenic bladder dysfunction, often called by the shortened term neurogenic bladder, refers to urinary bladder problems due to disease or injury of the central nervous system or peripheral nerves involved in the control of urination. There are multiple types of neurogenic bladder depending on the underlying cause and the symptoms. Symptoms include overactive bladder, urinary urgency, frequency, incontinence or difficulty passing urine. A range of diseases or conditions can cause neurogenic bladder including spinal cord injury, multiple sclerosis, stroke, brain injury, spina bifida, peripheral nerve damage, Parkinson's disease, multiple system atrophy or other neurodegenerative diseases. Neurogenic bladder can be diagnosed through a history and physical as well as imaging and more specialized testing. In addition to symptomatic treatment, treatment depends on the nature of the underlying disease and can be managed with behavioral changes, medications, surgeries, or other procedures. The symptoms of neurogenic bladder, especially incontinence, can severely degrade a person's quality of life.

Sacral nerve stimulation, also termed sacral neuromodulation, is a type of medical electrical stimulation therapy.

Bowel management is the process which a person with a bowel disability uses to manage fecal incontinence or constipation. People who have a medical condition which impairs control of their defecation use bowel management techniques to choose a predictable time and place to evacuate. A simple bowel management technique might include diet control and establishing a toilet routine. As a more involved practice a person might use an enema to relieve themselves. Without bowel management, the person might either suffer from the feeling of not getting relief, or they might soil themselves.

<span class="mw-page-title-main">Rectum</span> Final portion of the large intestine

The rectum is the final straight portion of the large intestine in humans and some other mammals, and the gut in others. The adult human rectum is about 12 centimetres (4.7 in) long, and begins at the rectosigmoid junction at the level of the third sacral vertebra or the sacral promontory depending upon what definition is used. Its diameter is similar to that of the sigmoid colon at its commencement, but it is dilated near its termination, forming the rectal ampulla. It terminates at the level of the anorectal ring or the dentate line, again depending upon which definition is used. In humans, the rectum is followed by the anal canal, which is about 4 centimetres (1.6 in) long, before the gastrointestinal tract terminates at the anal verge. The word rectum comes from the Latin rēctumintestīnum, meaning straight intestine.

Solitary rectal ulcer syndrome or SRUS is a chronic disorder of the rectal mucosa. It commonly occurs with varying degrees of rectal prolapse. The condition is thought to be caused by different factors, such as long term constipation, straining during defecation, and dyssynergic defecation. Treatment is by normalization of bowel habits, biofeedback, and other conservative measures. In more severe cases various surgical procedures may be indicated. The condition is relatively rare, affecting approximately 1 in 100,000 people per year. It affects mainly adults aged 30–50. Females are affected slightly more often than males. The disorder can be confused clinically with rectal cancer or other conditions such as inflammatory bowel disease, even when a biopsy is done.

<span class="mw-page-title-main">Anismus</span> Failure to relax the pelvic floor muscles during defecation

Anismus or dyssynergic defecation is the failure of normal relaxation of pelvic floor muscles during attempted defecation. It can occur in both children and adults, and in both men and women. It can be caused by physical defects or it can occur for other reasons or unknown reasons. Anismus that has a behavioral cause could be viewed as having similarities with parcopresis, or psychogenic fecal retention.

Obstructed defecation syndrome is a major cause of functional constipation, of which it is considered a subtype. It is characterized by difficult and/or incomplete emptying of the rectum with or without an actual reduction in the number of bowel movements per week. Normal definitions of functional constipation include infrequent bowel movements and hard stools. In contrast, ODS may occur with frequent bowel movements and even with soft stools, and the colonic transit time may be normal, but delayed in the rectum and sigmoid colon.

Dyssynergia is any disturbance of muscular coordination, resulting in uncoordinated and abrupt movements. This is also an aspect of ataxia. It is typical for dyssynergic patients to split a movement into several smaller movements. Types of dyssynergia include Ramsay Hunt syndrome type 1, bladder sphincter dyssynergia, and anal sphincter dyssynergia.

In fecal incontinence (FI), surgery may be carried out if conservative measures alone are not sufficient to control symptoms. There are many surgical options described for FI, and they can be considered in 4 general groups.

<span class="mw-page-title-main">Lumbar anterior root stimulator</span> Neuroprosthesis

A lumbar anterior root stimulator is a type of neuroprosthesis used in patients with a spinal cord injury or to treat some forms of chronic spinal pain. More specifically, the root stimulator can be used in patients who have lost proper bowel function due to damaged neurons related to gastrointestinal control and potentially allow paraplegics to exercise otherwise paralyzed leg muscles.

Transanal irrigation is medical procedure in which water is used to evacuate feces from the rectum and descending colon via the anus.

Low anterior resection syndrome is a complication of lower anterior resection, a type of surgery performed to remove the rectum, typically for rectal cancer. It is characterized by changes to bowel function that affect quality of life, and includes symptoms such as fecal incontinence, incomplete defecation or the sensation of incomplete defecation, changes in stool frequency or consistency, unpredictable bowel function, and painful defecation (dyschezia). Treatment options include symptom management, such as use of enemas, or surgical management, such as creation of a colostomy.

References

  1. ↑ "Sample records for neurogenic bowel dysfunction". science.gov. Science.gov. Archived from the original on 2018-09-29. Retrieved 2018-09-28.
  2. ↑ Emmanuel, A (2010-02-09). "Review of the efficacy and safety of transanal irrigation for neurogenic bowel dysfunction". Spinal Cord. 48 (9): 664–673. doi: 10.1038/sc.2010.5 . PMID   20142830.
  3. 1 2 3 Brookes, SJ; Dinning, PG; Gladman, MA (December 2009). "Neuroanatomy and physiology of colorectal function and defaecation: from basic science to human clinical studies". Neurogastroenterol Motil. 21: 9–19. doi:10.1111/j.1365-2982.2009.01400.x. PMID   19824934. S2CID   33885542.
  4. 1 2 Palit, Somnath; Lunniss, Peter J.; Scott, S. Mark (2012-02-26). "The Physiology of Human Defecation". Dig Dis Sci. 57 (6): 1445–1464. doi:10.1007/s10620-012-2071-1. PMID   22367113. S2CID   25173457.
  5. 1 2 3 4 5 6 Krogh, K; Christensen, P; Laurberg, S (June 2001). "Colorectal symptoms in patients with neurological diseases". Acta Neurol Scand. 103 (6): 335–343. doi: 10.1034/j.1600-0404.2001.103006335.x . PMID   11421845. S2CID   28090580.
  6. 1 2 3 Qi, Zhengyan; Middleton, James W; Malcolm, Allison (2018-08-29). "Bowel Dysfunction in Spinal Cord Injury". Curr Gastroenterol Rep. 20 (10): 47. doi:10.1007/s11894-018-0655-4. PMID   30159690. S2CID   52129284.
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  9. ↑ Coggrave, M; Norton, C; Wilson-Barnett, J (2008-11-18). "Management of neurogenic bowel dysfunction in the community after spinal cord injury: a postal survey in the United Kingdom". Spinal Cord. 47 (4): 323–333. doi: 10.1038/sc.2008.137 . PMID   19015665.
  10. 1 2 Gulick, EE (September 2022). "Neurogenic Bowel Dysfunction Over the Course of Multiple Sclerosis: A Review". International journal of MS care. 24 (5): 209–217. doi:10.7224/1537-2073.2021-007. PMC   9461721 . PMID   36090242.
  11. ↑ Branagan, G; Tromans, A; Finnis, D (2003). "Effect of stoma formation on bowel care and quality of life in patients with spinal cord injury". Spinal Cord. 41 (12): 680–683. doi: 10.1038/sj.sc.3101529 . PMID   14639447.
  12. 1 2 3 4 5 6 7 8 9 Pellatt, Glynis Collis (2008). "Neurogenic continence. Part 1: pathophysiology and quality of life". Br J Nurs. 17 (13): 836–841. doi:10.12968/bjon.2008.17.13.30534. PMID   18856146.
  13. 1 2 Cotterill, Nikki; Madersbacher, Helmut; Wyndaele, Jean J.; Apostolidis, Apostolos; Drake, Marcus J.; Gajewski, Jerzy; Heesakkers, John; Panicker, Jalesh; Radziszewski, Piotr (2017-06-22). "Neurogenic bowel dysfunction: Clinical management recommendations of the Neurologic Incontinence Committee of the Fifth International Consultation on Incontinence 2013". Neurourol Urodyn. 37 (1): 46–53. doi:10.1002/nau.23289. PMID   28640977. S2CID   206304249.
  14. 1 2 3 4 den Braber-Ymker, Marjanne; Lammens, Martin; van Putten, Michel J.A.M.; Nagtegaal, Iris D. (2017-01-06). "The enteric nervous system and the musculature of the colon are altered in patients with spina bifida and spinal cord injury". Virchows Archiv. 470 (2): 175–184. doi:10.1007/s00428-016-2060-4. PMC   5306076 . PMID   28062917.
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  17. ↑ Krogh, Klaus; Christensen, Peter (2009). "Neurogenic colorectal and pelvic floor dysfunction". Best Pract Res Clin Gastroenterol. 23 (4): 531–543. doi:10.1016/j.bpg.2009.04.012. PMID   19647688.
  18. ↑ Amarenco, G. (2014). "Bristol Stool Chart : étude prospective et monocentrique de " l'introspection fécale " chez des sujets volontaires". Progrès en Urol. 24 (11): 708–713. doi:10.1016/j.purol.2014.06.008. PMID   25214452.
  19. ↑ Faaborg, P M; Christensen, P; Rosenkilde, M; Laurberg, S; Krogh, K (2010-11-23). "Do gastrointestinal transit times and colonic dimensions change with time since spinal cord injury?". Spinal Cord. 49 (4): 549–553. doi: 10.1038/sc.2010.162 . PMID   21102573.
  20. 1 2 Gramlich, T.; Puet, T. (August 1998). "Long-term safety of pulsed irrigation evacuation (PIE) use with chronic bowel conditions". Digestive Diseases and Sciences. 43 (8): 1831–1834. doi:10.1023/a:1018808408880. ISSN   0163-2116. PMID   9724176. S2CID   35212840.
  21. ↑ McClurg, Doreen; Norton, Christine (2016-07-27). "What is the best way to manage neurogenic bowel dysfunction?". BMJ. 354: i3931. doi:10.1136/bmj.i3931. PMID   27815246. S2CID   28028731. Archived from the original on 2018-09-29. Retrieved 2018-09-18.
  22. ↑ Ray, Kausik; McFall, Malcolm (April 2010). "Large bowel enema through colostomy with a Foley catheter: a simple and effective technique". Annals of the Royal College of Surgeons of England. 92 (3): 263. doi:10.1308/rcsann.2010.92.3.263. ISSN   1478-7083. PMC   3080060 . PMID   20425893.
  23. ↑ Facts about Neurogenic Bladder Treatment
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