Negri bodies are found in:
**Core Concept**
Negri bodies are a key feature of rabies infection, representing the **pathognomonic** sign of this viral disease. They are **inclusion bodies** found within the cytoplasm of certain nerve cells. The presence of Negri bodies is crucial for the diagnosis of rabies.
**Why the Correct Answer is Right**
Negri bodies are characteristic of rabies virus infection and are typically found in the **hippocampus**, **cerebellum**, and **purkinje cells**. They are composed of **viral nucleoproteins** and are a result of the **replication** of the rabies virus within these cells. The formation of Negri bodies is a hallmark of the disease.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as it does not specify the correct location or context in which Negri bodies are found.
**Option B:** Similarly, this option lacks specificity regarding the association with rabies.
**Option C:** This option is also incorrect as it does not relate to the pathognomonic sign of rabies.
**Option D:** This option is incorrect because it is not associated with the characteristic inclusion bodies of rabies.
**Clinical Pearl / High-Yield Fact**
Negri bodies are a critical diagnostic feature of rabies, and their presence confirms the disease. It's essential to remember that not all rabies-infected individuals will have Negri bodies, but when present, they are **pathognomonic**.
**Correct Answer:** D. brain of a patient with rabies.