Lead point in intussusception - ?

[Lothric]

Hey,

What is meant by a lead point in the context of intussusception? I thought it was a structure that protrudes into the bowel lumen and thus is predisposed to telescope distally, but Meckel diverticulum does not protrude into the lumen and it is considered a lead point. So what's the definition?

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[Pepe18]

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[Lothric]

The diverticulum can invert on itself and go into the lumen of the bowel

lol, well that makes it clear then! Thank you Pepe!

 

[Phloston]

Hey,

What is meant by a lead point in the context of intussusception? I thought it was a structure that protrudes into the bowel lumen and thus is predisposed to telescope distally, but Meckel diverticulum does not protrude into the lumen and it is considered a lead point. So what's the definition?

Adults: lead point is malignancy almost always

Kids under age 2 (the vast, vast majority of your cases): GALT hyperplasia (e.g., from GI infection, vaccine responses, etc.)

 

[Fission Chips]

Can anyone expand on the most common cause? I learned it was GALT hyperplasia in lecture and Pathoma, but FA 2018 says it is from Meckel. Which one should we go with if that shows up on Step 1?

 

[SpartanWolverine]

Can anyone expand on the most common cause? I learned it was GALT hyperplasia in lecture and Pathoma, but FA 2018 says it is from Meckel. Which one should we go with if that shows up on Step 1?

In children the most common cause is "idiopathic" (75%) of which infection/lymphoid hyperplasia is lumped in. It seems to be unclear whether the enlarged Peyer patches are a reaction or cause of intussusception but there do seem to be correlations with preceding URI --> ? GALT hyperplasia --> lead point for intussusception.

Meckel's, however, is the most commonly identified pathological lesion found at the lead point.

It would be unlikely to have both options on Step.