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Hemorrhoids develop due to a combination of [[genetic predisposition]] (weak rectal [[veins]]) and certain diet and defecation habits.
Hemorrhoids develop due to a combination of [[genetic predisposition]] (weak rectal [[veins]]) and certain diet and defecation habits.
==Pathophysiology==
==Pathophysiology==
* The pathophysiology of hemorrhoids includes [[genetic predisposition]] (weak rectal [[vein]] walls and/or [[anal valves|valves]]), straining during [[Defecation|bowel movements]], and too much pressure on the rectal [[veins]] due to poor [[muscle tone]] or poor posture.<ref name="pmid28567655">{{cite journal |vauthors=Guttenplan M |title=The Evaluation and Office Management of Hemorrhoids for the Gastroenterologist |journal=Curr Gastroenterol Rep |volume=19 |issue=7 |pages=30 |year=2017 |pmid=28567655 |doi=10.1007/s11894-017-0574-9 |url=}}</ref>
 
* Similarly, sitting for prolonged periods of time can cause hemorrhoids.  
*Hemorrhoids can be internal and external.
* [[Portal hypertension]] can also cause hemorrhoids because of the connections between the [[portal vein]] and the [[vena cava]] that occur in the rectal wall, known as [[portocaval anastomoses]].<ref>{{cite web |title=Causes of Hemorrhoids |url=http://www.mayoclinic.com/health/hemorrhoids/DS00096/DSECTION=3 |date=Nov 28, 2006  |publisher=Mayo Clinic |accessdate=2007-12-07}}</ref>
 
* Additional factors that can influence the course of hemorrhoids (mostly by increasing rectal [[vein]] pressure), especially for those with a genetic predisposition, include [[obesity]] and a [[sedentary lifestyle]].<ref name="pmid17074235">{{cite journal |vauthors=Huang YT |title=[Consideration on the pathogenesis of hemorrhoids] |language=Chinese |journal=Zhonghua Wai Ke Za Zhi |volume=44 |issue=15 |pages=1019–21 |year=2006 |pmid=17074235 |doi= |url=}}</ref><ref name="pmid3265119">{{cite journal |vauthors=Le Quellec A, Bories P, Rochon JC, Garrigues JM, Poirier JL, Michel H |title=[Portal hypertension and hemorrhoids. Cause effect relationship?] |language=French |journal=Gastroenterol. Clin. Biol. |volume=12 |issue=8-9 |pages=646–8 |year=1988 |pmid=3265119 |doi= |url=}}</ref>
*Internal hemorrhoids are located above the dentate line and they occur due to dilatation of the superior hemorrhoidal plexus.
* Increased straining during bowel movements (e.g. [[constipation]], [[diarrhea]]) may lead to hemorrhoids.<ref name="titleHemorrhoids during pregnancy: Treatment options - MayoClinic.com">{{cite web |author=Harms R |title=Hemorrhoids during pregnancy: Treatment options |url=http://www.mayoclinic.com/health/hemorrhoids-during-pregnancy/AN01720 |date=Nov 3, 2007 |publisher=MayoClinic |accessdate=2007-11-28}}</ref>
 
* [[Pregnancy]] can cause [[hypertension]] and increases strain during bowel movements, so hemorrhoids are often associated with pregnancy.  
*The connective tissue over the superior hemorrhoidal plexus is innervated via visceral nerves and thus it is pain insensitive.
* Excessive consumption of [[alcohol]] or [[caffeine]] can cause hemorrhoids.<ref name="titleHemorrhoids">{{cite web |author=Burney RE |title=Hemorrhoids |url=http://www.med.umich.edu/1libr/aha/aha_hem_crs.htm |date=November 2005 |publisher=University of Michigan Health System |accessdate=2007-11-28}}</ref>
 
*External hemorrhoids are located below the dentate line and occur due to dilatation of the inferior hemorrhoidal plexus.
 
*The first step in the pathogenesis of either type of hemorrhoids is weakening of the surrounding connective tissue and vein wall. All the risk factors (old age, pregnancy, portal hypertension, etc) lead to aggravating this weakness or add more pressure from within the vein.
 
*Increased tone of the internal anal sphincter causing the feces to press the hemorrhoid against the muscle and thus decreasing venous return and aggravating the symptoms.
 
*The arteriovenous anastomosis may play a role in the development of hemorrhoids. This is supported by the fact that some hemorrhoids improve after ligating the connecting arteries.
   
*The redundant bulging mucosa is easily injured causing bleeding. The blood is usually bright red reflecting high oxygen content due to the proximity of AV anastomosis.


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===Food===
===Food===
* [[Chronic constipation]] can cause hemorrhoidal irritation due to hard stools.<ref name="pmid17074235" />
* [[Chronic constipation]] can cause hemorrhoidal irritation due to hard stools.<ref name="pmid17074235" />

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Ahmed Younes M.B.B.CH [2]

Overview

Hemorrhoids develop due to a combination of genetic predisposition (weak rectal veins) and certain diet and defecation habits.

Pathophysiology

  • Hemorrhoids can be internal and external.
  • Internal hemorrhoids are located above the dentate line and they occur due to dilatation of the superior hemorrhoidal plexus.
  • The connective tissue over the superior hemorrhoidal plexus is innervated via visceral nerves and thus it is pain insensitive.
  • External hemorrhoids are located below the dentate line and occur due to dilatation of the inferior hemorrhoidal plexus.
  • The first step in the pathogenesis of either type of hemorrhoids is weakening of the surrounding connective tissue and vein wall. All the risk factors (old age, pregnancy, portal hypertension, etc) lead to aggravating this weakness or add more pressure from within the vein.
  • Increased tone of the internal anal sphincter causing the feces to press the hemorrhoid against the muscle and thus decreasing venous return and aggravating the symptoms.
  • The arteriovenous anastomosis may play a role in the development of hemorrhoids. This is supported by the fact that some hemorrhoids improve after ligating the connecting arteries.
  • The redundant bulging mucosa is easily injured causing bleeding. The blood is usually bright red reflecting high oxygen content due to the proximity of AV anastomosis.

{{#ev:youtube|QKndv13bXHA}}

Food

  • Chronic constipation can cause hemorrhoidal irritation due to hard stools.[1]
  • An excess of lactic acid in the stool, a product of excessive consumption of dairy products such as cheese, can cause irritation. A reduction of consumption of these foods can bring relief.
  • Vitamin E deficiency is also a common cause.
  • Consuming probiotic foods such as yogurt with active culture or consuming fruit may help keep the gut functioning normally and prevent flare-ups.

Use of unnatural "sitting" toilets

  • Based on their very low incidence in the developing world, where people squat for bodily functions, hemorrhoids have been attributed to the use of the unnatural "sitting" toilet.[2][3]
  • In 1987, an Israeli physician, Dr. Berko Sikirov, published a study testing this hypothesis by having hemorrhoid sufferers convert to squat toilets.[4] Eighteen of the 20 patients were completely relieved of their symptoms (pain and bleeding) with no recurrence, even 30 months after completion of the study.
  • No follow-up studies have ever been published.
  • The American Society of Colon & Rectal Surgeons has not published any recommendations regarding the therapeutic value of squatting.

Gross pathology

  • External hemorrhoids appear on inspection of the anal verge as skin tags or strangulated or free prolapsed veins.
  • Internal hemorrhoids appear as bluish bulgings of the veins in the mucosa.
By Dr. Joachim Guntau - www.Endoskopiebilder.de, CC BY-SA 3.0, httpscommons.wikimedia.orgwindex.phpcurid=18660152
By Dr. Joachim Guntau - www.Endoskopiebilder.de, CC BY-SA 3.0, httpscommons.wikimedia.orgwindex.phpcurid=18660115
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By Internet Archive Book Images - httpswww.flickr.comphotosinternetarchivebookimages14784684835Source book page httpsarchive.orgstreamdiseasesofrectum00gantdiseasesofrectum00gant-pagen490mode1up, No restrictions, ht

References

  1. Sikirov BA (1989). "Primary constipation: an underlying mechanism". Med. Hypotheses. 28 (2): 71–3. PMID 2927355.
  2. Sikirov D (2003). "Comparison of straining during defecation in three positions: results and implications for human health". Dig. Dis. Sci. 48 (7): 1201–5. PMID 12870773.
  3. Sikirov BA (1987). "Management of hemorrhoids: a new approach". Isr. J. Med. Sci. 23 (4): 284–6. PMID 3623887.

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