Lower gastrointestinal bleeding causes: Difference between revisions

Jump to navigation Jump to search
← Older editNewer edit →
VisualWikitext
Aditya Ganti (talk | contribs)
Bureaucrats, bureaucrats, nocaptcha, Administrators
11,402 edits
Aditya Ganti (talk | contribs)
Bureaucrats, bureaucrats, nocaptcha, Administrators
11,402 edits
Line 7: Line 7:
Common causes of lower gastrointestinal bleeding inclue:
Common causes of lower gastrointestinal bleeding inclue:
*Colonic diverticulosis
*Colonic diverticulosis
**Colonic diverticulosisis the most common cause of acute LGIB in the western world, accounting for 15% to 55% of all LGIB
**Colonic diverticulosis is the most common cause of acute LGIB, accounting for 15% to 55% of all LGIB.
**Diverticula can occur anywhere in the gastrointestinal tract, but are most common in the sigmoid colon. However, approximately 60% of diverticular bleeds arise from diverticula in the right colon, highlighting a tendency for right-sided diverticula to bleed
**Hemorrhage results from rupture of the intramural branches (vasa recta) of the marginal artery at the dome of a diverticulum and can give rise to a massive, life-threatening LGIB.
**Hemorrhage results from rupture of the intramural branches (vasa recta) of the marginal artery at the dome of a diverticulum and can give rise to a massive, life-threatening LGIB
**Diverticulosis is the most common cause of bleeding in the elderly, as the prevalence of diverticular disease increases with age, being as high as 85% by the age of 85 years.
**This is by far the most common cause of bleeding in the elderly, as the prevalence of diverticular disease increases with age, being as high as 85% by the age of 85 years


* Obesity has recently been recognized as a risk factor in the development of diverticular disease, and the risk of diverticular bleeding in this group of patients is higher than that in patients who are not obese
* Vascular ectasias (angiodysplasias/angioectasias):
* Vascular ectasias (angiodysplasias/angioectasias):
** Tortuous dilated submucosal vessels that account for approximately 10% of LGIB.  
** Tortuous dilated submucosal vessels that account for approximately 10% of LGIB.  
** They appear endoscopically as small, flat lesions (5-10 mm) with ectatic capillaries radiating from a central vessel (Fig. 1)
** The prevalence of angiodysplasia is higher in older populations.
** The prevalence of angiodysplasia in the gastrointestinal tract is not well known, but a pooled analysis of three colonoscopic cancer screening studies detected angiodysplasia in 0.8% of the patients The prevalence of angiodysplasia is higher in older populations and, in the past, has been linked to certain conditions such as end-stage renal disease, Von Willebrand disease , and aortic stenosis In one series, 37% of colonic dysplasias were found in the cecum, 17% in the ascending colon, 7% in the transverse colon, 7% in the descending colon, and 32% in rectosigmoid area
** Angiodysplasia can also be found throughout the small bowel and is responsible for up to 40% of small intestinal bleeding in patients older than 40 years.
** Angiodysplasia can also be found throughout the small bowel and is responsible for up to 40% of small intestinal bleeding in patients older than 40 years.
** Angiodysplasia of the stomach and duodenum is responsible for up to 7% of UGIB I
** Angiodysplasia of the stomach and duodenum is responsible for up to 7% of UGIB.
* Iatrogenic:
* Iatrogenic:
** Bleeding is recognized as the most common complication of colonoscopy and polypectomy, occurring in 0.3% to 6.1% of polypectomies
** Bleeding is recognized as the most common complication of colonoscopy and polypectomy, occurring in 0.3% to 6.1% of polypectomies.
** Risk factors for bleeding include polyp size greater than 1 cm, patient age older than 65 years, presence of comorbid disease, and polypectomy using the cutting mode of current
** Risk factors for bleeding include polyp size greater than 1 cm, patient age older than 65 years, presence of comorbid disease, and polypectomy using the cutting mode of current.
** The risk is also greater in patients taking anticoagulant or antiplatelet agents
** The risk is also greater in patients taking anticoagulant or antiplatelet agents.
* Ischemic colitis:
* Ischemic colitis:
** Ischemic colitis accounts for approximately 20% of LGIB
** Ischemic colitis accounts for approximately 20% of LGIB
** Ischemia results from a sudden reduction in blood flow to the mesenteric vessels as a result of hypotension, occlusion, or spasm of the mesenteric vessels
** Nonocclusive disease typically affects the watershed areas of the bowels, such as the splenic flexure and adjacent transverse colon due to the poor blood supply from the marginal artery.
** Occlusive disease is rarer but can occur as a result of thrombus formation or embolus.
** It is a recognized complication of aortic surgery
** Elderly patients with comorbid disease are at higher risk of developing ischemic colitis.
** There may be a history of ischemic heart disease
** The majority of patients with ischemic colitis improve following conservative management; however, approximately 20% will progress to develop colonic gangrene
** Other complications include chronic colitis and stricture formation
** Diagnosis requires a high index of suspicion
* Colorectal malignancy:
* Colorectal malignancy:
** Colorectal cancer accounts for approximately 10% of bleeds, either as occult bleeding presenting with anemia or as frank blood loss per rectum
** Colorectal cancer accounts for approximately 10% of bleeds, either as occult bleeding presenting with anemia or as frank blood loss per rectum
** A family history of colorectal cancer is important to establish
* Anorectal abnormalities:
* Anorectal abnormalities:
** Hemorrhoids, fissures, fistulae, and polyps can all present with bright red rectal bleeding, which may be intermittent in nature
** Hemorrhoids, fissures, fistulae, and polyps can all present with bright red rectal bleeding, which may be intermittent in nature
** Hemorrhoids are the most common cause of rectal bleeding in adults younger than 50 years
** Hemorrhoids are the most common cause of rectal bleeding in adults younger than 50 years
** The finding of hemorrhoids in older patients with LGIB should not preclude further investigation, as hemorrhoids are an extremely common finding and may not be the cause of bleeding
* Inflammatory bowel disease (IBD):
* Inflammatory bowel disease (IBD):
** IBD refers to both Crohn disease and ulcerative colitis Accounts for 5% to 10% of bleeds.
** IBD refers to both Crohn disease and ulcerative colitis accounts for 5% to 10% of bleeds.
** It is by far the most common cause of LGIB in Asian populations in whom the prevalence of diverticular disease is much lower
** It is by far the most common cause of LGIB in Asian populations in whom the prevalence of diverticular disease is much lower.
** A previous history of IBD in patients with LGIB is important, as these patients have a higher risk of developing colorectal malignancy than do the general population
* Infectious colitis:
* Infectious colitis:
** The most common organisms in the U.S. are species ofSalmonella,Campylobacter,Shigella, andYersinia
** The most common organisms in the U.S. are species of Salmonella, Campylobacter, Shigella, and Yersinia.


===Less common causes===
===Less common causes===
Less common causes of lower gastrointestinal bleeding include:
Less common causes of lower gastrointestinal bleeding include:
* Colonic polyps:
* Colonic polyps
** These can occur in isolation or as part of an inherited polyposis syndrome
** Can cause occult or overt LGIB


* Radiation proctitis:
* Radiation proctitis
** This usually occurs a few months following ionizing radiation for pelvic malignancies (Fig. 2). In one study of patients with radiation proctitis following pelvic irradiation, 69% presented with bleeding within 1 year and 96% within 2 years


* Rectal varices:
* Rectal varices
** Associated with portal hypertension; may result in massive bleeding
* Stercoral ulceration
** Stercoral ulceration:
** Can cause significant fresh rectal bleeding in elderly constipated patients


* Meckel diverticulum:
* Meckel diverticulum
** These small bowel diverticula may contain ectopic gastric mucosa that can ulcerate and cause bleeding
** They are the most common cause of massive LGIB in young children, and can be diagnosed with angiography, Meckel scans, and radionuclide imaging


* Intussusception :
* Intussusception  
** More common in children, with the highest incidence between the ages of 6 months and 2 years
* Henoch-Schönlein purpura (HSP)
* Henoch-Schönlein purpura (HSP):
** Most commonly affects children
** Bleeding may be a direct result of vasculitis or secondary to intussusception, which is associated with HSP
* Aortoenteric fistula:
 
* Abdominal aortic aneurysms, especially those of the inflammatory type, may fistulate into the small bowel, giving rise to a massive, life-threatening hemorrhage
 
* Peutz-Jeghers syndrome:
** Polyps may give rise to frank or occult bleeding
* Klippel-Trenaunay-Weber syndrome:
** Hemangiomas in the colon can cause significant bleeding
 
* Hereditary hemorrhagic telangiectasia:
** Blood loss from mucosal telangiectasia can be chronic or acute
* Neurofibromatosis :
** Neurofibromas within the lumen of the bowel can ulcerate, causing bleeding
* Blue rubber bleb syndrome:
** Bleeding can arise from hemangiomas in the bowel Usually occult in nature


==References==
==References==

Revision as of 21:32, 13 December 2017

Lower gastrointestinal bleeding Microchapters

Home

Patient Information

Overview

Historical Perspective

Classification

Pathophysiology

Causes

Differentiating Lower gastrointestinal bleeding from other Diseases

Epidemiology and Demographics

Risk Factors

Screening

Natural History, Complications and Prognosis

Diagnosis

Diagnostic Study of Choice

History and Symptoms

Physical Examination

Laboratory Findings

Electrocardiogram

X-ray

Echocardiography and Ultrasound

CT scan

MRI

Other Imaging Findings

Other Diagnostic Studies

Treatment

Management

Initial resuscitation
Pharmacotherapy

Surgery

Surgical Management
Endoscopic Intervention

Primary Prevention

Secondary Prevention

Cost-Effectiveness of Therapy

Future or Investigational Therapies

Guidelines for Management

Case Studies

Case #1

Lower gastrointestinal bleeding causes On the Web

Most recent articles

Most cited articles

Review articles

CME Programs

Powerpoint slides

Images

American Roentgen Ray Society Images of Lower gastrointestinal bleeding causes

All Images
X-rays
Echo & Ultrasound
CT Images
MRI

Ongoing Trials at Clinical Trials.gov

US National Guidelines Clearinghouse

NICE Guidance

FDA on Lower gastrointestinal bleeding causes

CDC on Lower gastrointestinal bleeding causes

Lower gastrointestinal bleeding causes in the news

Blogs on Lower gastrointestinal bleeding causes

Directions to Hospitals Treating Psoriasis

Risk calculators and risk factors for Lower gastrointestinal bleeding causes

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

Overview

Causes

Common causes

Common causes of lower gastrointestinal bleeding inclue:

  • Colonic diverticulosis
    • Colonic diverticulosis is the most common cause of acute LGIB, accounting for 15% to 55% of all LGIB.
    • Hemorrhage results from rupture of the intramural branches (vasa recta) of the marginal artery at the dome of a diverticulum and can give rise to a massive, life-threatening LGIB.
    • Diverticulosis is the most common cause of bleeding in the elderly, as the prevalence of diverticular disease increases with age, being as high as 85% by the age of 85 years.
  • Vascular ectasias (angiodysplasias/angioectasias):
    • Tortuous dilated submucosal vessels that account for approximately 10% of LGIB.
    • The prevalence of angiodysplasia is higher in older populations.
    • Angiodysplasia can also be found throughout the small bowel and is responsible for up to 40% of small intestinal bleeding in patients older than 40 years.
    • Angiodysplasia of the stomach and duodenum is responsible for up to 7% of UGIB.
  • Iatrogenic:
    • Bleeding is recognized as the most common complication of colonoscopy and polypectomy, occurring in 0.3% to 6.1% of polypectomies.
    • Risk factors for bleeding include polyp size greater than 1 cm, patient age older than 65 years, presence of comorbid disease, and polypectomy using the cutting mode of current.
    • The risk is also greater in patients taking anticoagulant or antiplatelet agents.
  • Ischemic colitis:
    • Ischemic colitis accounts for approximately 20% of LGIB
  • Colorectal malignancy:
    • Colorectal cancer accounts for approximately 10% of bleeds, either as occult bleeding presenting with anemia or as frank blood loss per rectum
  • Anorectal abnormalities:
    • Hemorrhoids, fissures, fistulae, and polyps can all present with bright red rectal bleeding, which may be intermittent in nature
    • Hemorrhoids are the most common cause of rectal bleeding in adults younger than 50 years
  • Inflammatory bowel disease (IBD):
    • IBD refers to both Crohn disease and ulcerative colitis accounts for 5% to 10% of bleeds.
    • It is by far the most common cause of LGIB in Asian populations in whom the prevalence of diverticular disease is much lower.
  • Infectious colitis:
    • The most common organisms in the U.S. are species of Salmonella, Campylobacter, Shigella, and Yersinia.

Less common causes

Less common causes of lower gastrointestinal bleeding include:

  • Colonic polyps
  • Radiation proctitis
  • Rectal varices
  • Stercoral ulceration
  • Meckel diverticulum
  • Intussusception
  • Henoch-Schönlein purpura (HSP)

References

Template:WH Template:WS

Retrieved from "https://www.wikidoc.org/index.php?title=Lower_gastrointestinal_bleeding_causes&oldid=1405967"