Which description best fits pityriasis rosea?

Which description best fits pityriasis rosea?

• A. Lesions arranged in a Christmas-tree pattern on the trunk
• B. Pruritic vesicles on palms and soles
• C. Widespread flaky lesions on the scalp
• D. Linear streaks along the limbs

Answer: (A)

Pityriasis rosea typically starts with a single herald patch and then develops many similar oval patches that spread in a Christmas-tree pattern down the trunk, following the natural lines of skin cleavage. This distinctive distribution—lesions arranged diagonally along the trunk in a stepped, tree-like arrangement—is what makes pityriasis rosea recognizable. The eruption is usually mildly pruritic and self-limited over several weeks, often improving as the patches scale and fade. The other descriptions don’t fit this condition as well. Vesicles on the palms and soles point more toward hand-foot-and-mouth disease or pompholyx, not the trunk-limited, collarette-scaling plaques of pityriasis rosea. Widespread flaky scalp suggests seborrheic dermatitis or tinea capitis, not a trunk-predominant exanthem with a Christmas-tree pattern. Linear streaks along the limbs are not the classic trunk-focused, patterned eruption seen in pityriasis rosea.

Pityriasis rosea typically starts with a single herald patch and then develops many similar oval patches that spread in a Christmas-tree pattern down the trunk, following the natural lines of skin cleavage. This distinctive distribution—lesions arranged diagonally along the trunk in a stepped, tree-like arrangement—is what makes pityriasis rosea recognizable. The eruption is usually mildly pruritic and self-limited over several weeks, often improving as the patches scale and fade.

The other descriptions don’t fit this condition as well. Vesicles on the palms and soles point more toward hand-foot-and-mouth disease or pompholyx, not the trunk-limited, collarette-scaling plaques of pityriasis rosea. Widespread flaky scalp suggests seborrheic dermatitis or tinea capitis, not a trunk-predominant exanthem with a Christmas-tree pattern. Linear streaks along the limbs are not the classic trunk-focused, patterned eruption seen in pityriasis rosea.