Meckels_Diverticulum_Flashcards
What is Meckel’s diverticulum?
Meckel’s diverticulum is a congenital diverticulum of the small intestine, a remnant of the omphalomesenteric duct. It often contains ectopic mucosa such as ileal, gastric, or pancreatic.
What is the Rule of 2s associated with Meckel’s diverticulum?
The Rule of 2s states it occurs in 2% of the population, is located 2 feet from the ileocaecal valve, and is typically 2 inches long.
What are common presentations of Meckel’s diverticulum?
It often presents as abdominal pain mimicking appendicitis, rectal bleeding, or intestinal obstruction due to an omphalomesenteric band, volvulus, or intussusception.
Why is Meckel’s diverticulum significant in children aged 1 to 2 years?
It is the most common cause of painless massive GI bleeding requiring transfusion in children between 1 and 2 years of age.
What is a Meckel’s scan and when is it used?
A Meckel’s scan uses 99m technetium pertechnetate, which has an affinity for gastric mucosa, used in cases of less severe or intermittent bleeding to diagnose Meckel’s diverticulum.
What are the management options for Meckel’s diverticulum?
Management involves removal if it has a narrow neck or is symptomatic. Options include wedge excision or formal small bowel resection and anastomosis.
What is the pathophysiology of Meckel’s diverticulum?
Originally, it forms from the vitellointestinal duct’s attachment to the yolk sac, disappearing at 6 weeks gestation. It may be lined by ileal or ectopic gastric, pancreatic, or jejunal mucosa, with complications such as peptic ulceration.
summarise Meckels diverticulum
Meckel’s diverticulum
Meckel’s diverticulum is a congenital diverticulum of the small intestine. It is a remnant of the omphalomesenteric duct (also called the vitellointestinal duct) and contains ectopic ileal, gastric or pancreatic mucosa.
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Rule of 2s
occurs in 2% of the population
is 2 feet from the ileocaecal valve
is 2 inches long
Presentation (usually asymptomatic)
abdominal pain mimicking appendicitis
rectal bleeding
Meckel’s diverticulum is the most common cause of painless massive GI bleeding requiring a transfusion in children between the ages of 1 and 2 years
intestinal obstruction
secondary to an omphalomesenteric band (most commonly), volvulus and intussusception
Investigation
if the child is haemodynamically stable with less severe or intermittent bleeding then a ‘Meckel’s scan’ should be considered
uses 99m technetium pertechnetate, which has an affinity for gastric mucosa
mesenteric arteriography may also be used in more severe cases e.g. transfusion is required
Management
removal if narrow neck or symptomatic
options are between wedge excision or formal small bowel resection and anastomosis
Pathophysiology
normally, in the foetus, there is an attachment between the vitellointestinal duct and the yolk sac. This disappears at 6 weeks gestation
the tip is free in the majority of cases
associated with enterocystomas, umbilical sinuses, and omphaloileal fistulas.
arterial supply: omphalomesenteric artery.
typically lined by ileal mucosa but ectopic gastric mucosa can occur, with the risk of peptic ulceration. Pancreatic and jejunal mucosa can also occur.
A 20-month-old child has been admitted following a massive rectal bleed requiring transfusion. The child is settled and does not appear to be in pain.
What is the most likely diagnosis?
Meckel’s diverticulum
Oesophagitis
Anal fissure
Necrotising enterocolitis
Inflammatory bowel disease
Meckels diverticulum is the number one cause of painless massive GI bleeding requiring a transfusion in children between the ages of 1 and 2 years.
Important for meLess important
Meckel’s diverticulum is a congenital disorder causing malformation in the small intestine. There is an out-pouching from the small intestine, formed by the remnant of the umbilical cord. Often this disorder is asymptomatic, however, it can release acid, ulcerating the small intestine. Consequently, this condition is the most common cause of gastrointestinal bleeding requiring transfusion in under 2-year-olds, presenting with bright red rectal bleeding, constipation, nausea and vomiting, and abdominal pain.
Oesophagitis, where the oesophagus lining has become inflamed, is most commonly caused by acid reflux and classically presents with heartburn. If very severe it may cause bleeding but this blood would be found in vomit, not as bright red rectal bleeding.
An anal fissure is a common cause of blood per rectum, particularly in those who have been constipated. However, this blood is more commonly painful or itchy, unlike Meckel’s diverticulum. Furthermore, this is not commonly a cause for transfusion.
Necrotising enterocolitis, where the intestine becomes inflamed and necrotic, causes gastrointestinal bleeding and makes a child very unwell. However, this condition is far more common in neonates, particularly those born prematurely. It is less likely here than Meckel’s diverticulum.
Inflammatory bowel disease can cause rectal bleeding which may rarely be severe and require a blood transfusion. However, it is usually diagnosed in older children, with the most common age of onset being 15 years and above.
An 18 month old boy is brought to the emergency room by his parents. He was found in bed with a nappy filled with dark red blood. He is haemodynamically unstable and requires a blood transfusion. Prior to this episode he was well with no prior medical history. What is the most likely cause?
Necrotising enterocolitis
Anal fissure
Oesophageal varices
Meckels diverticulum
Crohns disease
Meckels diverticulum
Meckels diverticulum is the number one cause of painless massive GI bleeding requiring a transfusion in children between the ages of 1 and 2 years.
