**Meckel's Diverticulitis Core Concept**
Meckel's diverticulitis is an inflammatory condition of the Meckel's diverticulum, a true diverticulum of the ileum that arises from a persistent vitelline duct. This condition is often a complication of a Meckel's diverticulum, which is a congenital anomaly.

**Why the Correct Answer is Right**
Meckel's diverticulitis typically presents with symptoms such as abdominal pain, nausea, vomiting, and gastrointestinal bleeding. The condition is often caused by the inflammation of the Meckel's diverticulum due to the presence of ectopic gastric mucosa, which leads to acid production and subsequent inflammation. The inflammation can cause the diverticulum to become obstructed, leading to further complications.

**Why Each Wrong Option is Incorrect**
**Option A:** Meckel's diverticulitis is often asymptomatic. This is incorrect because Meckel's diverticulitis typically presents with symptoms such as abdominal pain, nausea, vomiting, and gastrointestinal bleeding.

**Option B:** Meckel's diverticulitis is caused by the inflammation of the Meckel's diverticulum due to the presence of ectopic gastric mucosa. This is correct, so we will not discuss it further.

**Option C:** Meckel's diverticulitis is often a complication of a Meckel's diverticulum, which is a congenital anomaly. This is correct, so we will not discuss it further.

**Option D:** Meckel's diverticulitis is commonly associated with a Meckel's diverticulum containing pancreatic tissue. This is incorrect because Meckel's diverticulitis is most commonly associated with a Meckel's diverticulum containing ectopic gastric mucosa, not pancreatic tissue.

**Clinical Pearl / High-Yield Fact**
A Meckel's diverticulum containing ectopic gastric mucosa is the most common cause of Meckel's diverticulitis. This is a high-yield fact for exam purposes, and it is essential to remember that ectopic gastric mucosa is the primary cause of Meckel's diverticulitis.

**Correct Answer: D. Meckel's diverticulitis is commonly associated with a Meckel's diverticulum containing pancreatic tissue.**