Raspberry tongue is a feature of
**Core Concept**
Raspberry tongue, also known as strawberry tongue, is a clinical sign characterized by a red, swollen, and prominent papillae on the surface of the tongue. This condition is often associated with acute rheumatic fever, a complication of untreated streptococcal pharyngitis.
**Why the Correct Answer is Right**
The correct answer is associated with acute rheumatic fever due to the formation of autoantibodies against streptococcal antigens. These autoantibodies trigger an immune response that leads to inflammation and damage to the heart, joints, and skin. The inflammation of the tongue is thought to be a result of the immune complex deposition and the release of various cytokines. The characteristic red and swollen papillae are due to the increased blood flow and edema in the tongue.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because the correct answer is specifically associated with acute rheumatic fever, whereas option A might be related to other conditions.
**Option B:** This option is incorrect because it is not directly related to the clinical sign of raspberry tongue.
**Option C:** This option is incorrect because it is not a correct association with raspberry tongue.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that the presence of a raspberry tongue in conjunction with a history of recent streptococcal infection should raise suspicion for acute rheumatic fever, and prompt further investigation and treatment.
**Correct Answer: D. Acute rheumatic fever.**