Gastrointestinal Bleeding Flashcards
How is gastrointestinal bleeding classified?
Gastrointestinal bleeding (GIB) is broadly divided into upper and lower GIB.
Upper GIB arises from the esophagus, stomach or duodenum, proximal to the ligament of Treitz, while lower GIB arises distally in the small bowel, colon and rectum.
Though there are many commonalities, it is useful to consider the etiology, presentation, diagnosis and treatment of upper and lower GIB separately.
What are the signs and symptoms of gastrointestinal bleeding?
Gastrointestinal bleeding may present in a variety of ways depending on the location, underlying cause, and pace of the bleeding.
Common terminology used to describe GIB includes hematemesis, vomitus containing frank blood; coffee ground emesis, vomitus containing black or dark brown material representing digested blood; melena, dark, tarry stools containing blood from a proximal source; and hematochezia, the passage of frank blood from the rectum [1, 3].
Depending on the underlying etiology, other symptoms such as abdominal pain, nausea and vomiting may accompany bleeding and help to guide the diagnostic workup [2].
Obscure GIB refers to bleeding without an identifiable source despite thorough workup [1].
Slow bleeding from any location in the GI tract may present as anemia without overt signs of bleeding, and is termed occult.
How does upper gastrointestinal bleeding present?
Upper GIB most commonly presents with hematemesis, followed by melena and finally coffee ground emesis [2, 4].
Uncommonly, brisk upper GIB may present with hematochezia [2, 3].
How does lower gastrointestinal bleeding present?
Lower GIB characteristically presents with hematochezia, but slower, more proximal sources of lower GIB may also present with melena [2, 3].
How common is gastrointestinal bleeding in children?
Data describing the incidence of GIB in children are sparse.
In a review of emergency department admissions from a nationally representative sample of US-based pediatric hospitals from 2006 to 2011, GIB accounted for approximately 1.5% of all ED visits.
Upper GIB accounted for 20% of these visits, lower GIB for 30%, and the location of bleeding was not specified in the remaining 50%.
Over the time period studied, the rate of GIB-associated ED visits increased from 82.2 to 93.9 per 100,000 children per year [5].
What are the most common causes of upper gastrointestinal bleeding?
The differential diagnosis in children presenting with upper GIB is broad and depends on age, as shown in Table 1.
The most common etiologies include gastritis, peptic ulcers (often H.pylori related), and vomiting induced hematemesis, which includes Mallory-Weiss tears and prolapse gastropathy syndrome [1, 2, 4].
What are the most common causes of lower gastrointestinal bleeding?
As with upper GIB, the differential diagnosis for children presenting with lower GIB depends on age and is shown in Table 2.
The most common etiologies include colorectal polyps, inflammatory bowel disease (IBD) and both infectious and non-infectious colitis [1–3].
What are the initial priorities in children with gastrointestinal bleeding?
Prior to embarking on an extensive diagnostic workup, patients should be rapidly assessed for hemodynamic stability.
Hemodynamically unstable patients may present with tachycardia, tachypnea, orthostatic hypotension, or altered mental status.
In these patients, prompt resuscitation with isotonic fluid and/ or blood products is the first priority.
Initial laboratory studies should include a complete blood count, electrolytes, liver function panel, and coagulation tests to help quantify the severity of blood loss, clarify comorbid conditions and identify bleeding diathesis. Severe ongoing blood loss or persistent hypotension necessitates urgent surgical, angiographic, or endoscopic intervention to control the bleeding [1–3].
Does acid suppression benefit children with gastrointestinal bleeding?
Medical therapy for pediatric GIB should be directed by the suspected etiology of the bleeding.
For patients with upper GIB, treatment with proton pump inhibitors (PPIs) has been shown to reduce the rate of re-bleeding, transfusion requirement, and need for surgery [1].
In addition, administration of a PPI in the first 48 h is associated with lower mortality [6].
What is the medical treatment for patients with portal hypertension and gastrointestinal bleeding?
In patients with portal hypertension and GIB, treatment with somatostatin or the somatostatin analog octreotide, vasopressin, or non-selective beta-blockers reduces portal venous pressure, decreasing variceal bleeding [1].
Endoscopy can be used prophylactically to prevent progression to variceal bleeding.
What is the role of endoscopy in the diagnosis of gastrointestinal bleeding?
Endoscopy, including esophagogastroduodenoscopy (EGD) and colonoscopy is the diagnostic test of choice in children with GIB, with the patient’s presentation determining the initial test [2–4].
Those presenting with hematochezia, suggesting a lower GIB should undergo colonoscopy first, while those presenting with melena or hematemesis, suggesting a proximal source, should undergo EGD [2].
What are the next steps in patients with a negative EGD and colonoscopy?
The diagnostic yield of repeat colonoscopy or EGD is low in these patients, and there is no established algorithm which can be applied to all patients [2, 3].
In patients with painless lower GIB, technetium-99 pertechnetate disodium scintigraphy (Meckel scan) can be used to diagnose Meckel’s diverticulum with a sensitiv- ity of 89.7% and specificity of 97.1% [7].
Cross sectional imaging, including CT and MRI, can also be used to located a Meckel’s diverticulum or bleeding tumor, and double-balloon enteroscopy or video capsule enteroscopy can identify luminal bleeding inaccessible by EGD or colonoscopy [3].
Due to the risk of capsule retention, the latter technique should not be used when there is suspicion for an stricture or tumor.
A technetium labeled red blood cell scan, or angiography may also be used to localize GIB, but both of these techniques require relatively brisk bleeding [3].
Ultimately, the source of GIB will not be identified in 10–20% of patients who present with GIB [2, 4].
What is the role of endoscopy in the treatment of gastrointestinal bleeding?
Endoscopy is employed both diagnostically and therapeutically in pediatric GIB.
Hemostasis can be achieved endoscopically using injection of epinephrine or sclerosants, electrocautery, argon beam coagulation, or application of clips [1, 3].
What is the role of interventional radiology in gastrointestinal bleeding?
For patients who present with brisk, arterial GIB, mesenteric angiography can be
used both to identify the site, and to embolize the offending vessel [1, 3].
When is surgery indicated for pediatric gastrointestinal bleeding?
Surgical intervention is generally reserved for patients with significant ongoing bleeding refractory to endoscopic treatment, hemodynamic instability, signs of peritonitis, bleeding tumor, or Meckel’s diverticulum [2, 7].
What is a Meckel’s diverticulum?
A Meckel’s diverticulum is a remnant of the vitelline duct which manifests as an outpouching of the distal small bowel.
According to the approximately correct and easily remembered “rule of 2’s” which states that they occur in 2% of the population, within 2 feet of the ileocecal valve, are 2 inches in length, with 2 possible types of heterotopic tissue (gastric and pancreatic), and present before the age of 2 [7].
How often does a Meckel’s diverticulum present with bleeding?
Meckel’s diverticula most commonly present with painless lower GIB, intestinal obstruction, or local inflammation which may mimic appendicitis. Roughly 25% of symptomatic Meckel’s diverticula in children will present with GIB [7].
How is a bleeding Meckel’s diverticulum managed?
A Meckel scan will reveal the diverticulum due to uptake of the radiotracer in heterotopic gastric mucosa, though false positives and negatives are possible, and other modalities including cross sectional imaging or angiography identifying the vitelline artery as the source of GIB can be used to make the diagnosis.
The treatment of a bleeding Meckel’s diverticula is surgical resection, either via a laparo- scopic or open approach [7].
What is the prognosis for children with gastrointestinal bleeding?
The prognosis for pediatric patients with GIB is generally excellent.
Roughly 80% of pediatric ED visits for GIB are discharged from the ED, suggesting that the majority of children with GIB have a relatively benign course [5].
In a nationally representative database study of children with GIB, the overall mortality was 2.07%.
However among patients whose principal diagnosis was GIB, the mortality was only 0.37%, demonstrating the favorable prognosis of isolated GIB compared to GIB in the setting of other significant illness [6].
A previously well 3-year-old presented with an upper respiratory tract infection and had been retching and vomiting small amounts of blood. She is growing well and has a normal examination. The most likely diagnosis is:
A non-steroidal anti-inflammatory drug gastropathy
B Mallory–Weiss’s tear
C haemorrhagic gastritis
D peptic ulcer
E vascular malformation
B
A mallory–Weiss’s tear is an acute mucosal laceration of the gastric cardia or gastro-oesophageal junction.
The classic presentation is haematemesis following repeated retching or vomiting.
Abdominal pain is uncommon and is most likely to be musculoskeletal in origin because of the forceful retching.
Vomiting episodes are usually related to a concurrent viral illness, and occur in previously well children with normal growth patterns and with no history of vomiting or loose stools.
SPSE 1
Most gastrointestinal (GI) stromal tumours are found in the
A mesentery
B stomach
C retroperitoneum
D omentum
E duodenum.
B
GI stromal tumours are mesenchymal tumours arising from the GI wall, mesentery, omentum and retroperitoneum.
most GI stromal tumours are found in the stomach (60%–70%) and should be considered in a patient with neurofibromatosis.
SPSE 1
The investigation of choice for evaluating haematemesis is:
A barium swallow
B upper GI endoscopy
C pH study
D Helicobacter pylori antigen in stool
E breath test for H. pylori.
B
upper GI endoscopy is the test of choice for evaluating haematemesis.
The aims of endoscopy are to identify the site of bleeding and to initiate therapeutic interventions as and when necessary.
Emergency endoscopy is only indicated when the bleed is ongoing and life-threatening.
most centres use general anaesthesia and control of the upper airways in children.
SPSE 1
The most likely diagnosis in a 18-month-old baby with an antecedent viral illness followed by sudden onset of colicky abdominal pain, tenderness and passage of ‘redcurrant jelly’ in stools is:
A Meckel’s diverticulum
B intussusception
C irritable bowel syndrome
D portal hypertension
E von Willebrand’s disease.
B
Idiopathic intussusception should be the working diagnosis for any child younger than 2 years of age who presents with abdominal pain or tenderness associated with lower GI blood loss.
The sudden onset of colicky abdominal pain and vomiting with antecedent viral illness, followed by redcurrant jelly stool is intussusception until proved otherwise.
Beyond 2 years, intussusception is most likely to be associated with a lead point such as meckel’s diverticulum, polyp, lymphoid nodular hyperplasia, foreign body, intramural haematoma, lymphoma or bowel wall oedema in relation to Henoch–Schönlein’s purpura.
SPSE 1
A previously well 2-year-old has painless rectal bleeding. She has normal growth and a normal examination. She also has soft stools and opens her bowels once every day. She is haemodynamically stable. The investigation that would help make the diagnosis is:
A colonoscopy
B Technetium-99m (99m Tc) scan
C abdominal X-ray
D cow’s-milk-free trial
E all of the above.
B
In any child who presents with painless, frank bleeding per rectum, the possible diagnosis are meckel’s diverticulum, polyp, intestinal duplication, intestinal submucosal mass or angiodysplasia. meckel’s diverticulum is a vestigial remnant of the omphalomesenteric duct located on the antimesenteric border in the distal ileum that occurs in 1.5%–2% of the general population.
A meckel’s diverticulum that contains gastric mucosa may present as painless acute lower GI bleed.
After exclusion of an intussusception, the next step in evaluation of haematochezia is a99m Tc pertechnetate scan. The radionuclide binds strongly to gastric mucosa in the meckel’s diverticulum, which forms a focus in the right lower quadrant. The radionuclide may also be taken up by the gastric heterotopias in the small-bowel mucosa or enteric duplications.
SPSE 1