A 28-year-old male patient is rushed to the emergency depament with chief complaints of fever, acute abdominal pain and leukocytosis suggestive of acute appendicitis. Emergency laparotomy is planned. However, during surgery following finding is noted. There are numerous enlarged mesenteric lymph nodes present. The likely diagnosis if infective could be

**Core Concept**
In acute appendicitis, the clinical presentation may sometimes be atypical, leading to diagnostic challenges. The presence of enlarged mesenteric lymph nodes during surgery can indicate a specific condition that needs to be differentiated from simple appendicitis.

**Why the Correct Answer is Right**
In the context of acute appendicitis, the presence of enlarged mesenteric lymph nodes is highly suggestive of **typhlitis**, also known as ileocecal tuberculosis (IC TB) or ileocecal lymphadenitis. This condition is characterized by inflammation of the ileocecal region and is often associated with tuberculosis. The lymphadenopathy in this region can be due to the body's immune response to the Mycobacterium tuberculosis infection. The enlarged lymph nodes can cause symptoms such as fever, abdominal pain, and leukocytosis, which are similar to those seen in acute appendicitis.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is not a viable choice as it does not provide a specific diagnosis related to the presence of enlarged mesenteric lymph nodes in the context of acute appendicitis.
* **Option B:** While this option might seem plausible, it is not the correct answer as it does not specifically address the presence of enlarged mesenteric lymph nodes in the context of acute appendicitis.
* **Option D:** This option is not a correct answer as it does not provide a specific diagnosis related to the presence of enlarged mesenteric lymph nodes in the context of acute appendicitis.

**Clinical Pearl / High-Yield Fact**
When encountering atypical presentation of acute appendicitis, consider the possibility of typhlitis or ileocecal tuberculosis, which can present with enlarged mesenteric lymph nodes. Remember that the presence of these lymph nodes can sometimes lead to diagnostic confusion, so it's essential to consider alternative diagnoses.

**Correct Answer:** C.

✓ Correct Answer: B. Yersinia pseudotuberculosis