**Question:** Darier's sign is associated with ?

A. Pityriasis Alba
B. Pityriasis Alba
C. Pityriasis Rubra Pilaris
D. Pityriasis Alba

**Correct Answer:** C. Pityriasis Rubra Pilaris

**Core Concept:** Darier's sign is an important clinical sign in dermatology, which is indicative of certain skin disorders. Darier's sign is characterized by the presence of small, whitish keratin plugs forming papules on the skin folds.

**Why the Correct Answer is Right:** Darier's sign is associated with Pityriasis Rubra Pilaris (PRP) because this condition is characterized by the proliferation of keratinocytes and the formation of keratin plugs within the hair follicles, leading to the appearance of these whitish papules. PRP is a rare, rapidly progressive, and potentially life-threatening dermatological disorder that affects both children and adults.

**Why Each Wrong Option is Incorrect:**

A. Pityriasis Alba (PA) is a common, self-limiting dermatological condition, predominantly affecting children. PA does not present with Darier's sign, making it an incorrect choice.

B. Similar to option A, Pityriasis Alba is also a common dermatological condition, which does not present with Darier's sign.

C. Pityriasis Rubra Pilaris is the correct answer, as mentioned above.

**Clinical Pearl:** Darier's sign is crucial for dermatologists to recognize and diagnose Pityriasis Rubra Pilaris, as early intervention and treatment are essential in managing this potentially life-threatening condition. Prompt diagnosis and treatment can prevent complications like infections, organ involvement, and even mortality in severe cases.