Which description best matches a bluish hue noted on a newborn's sacral area?

Which description best matches a bluish hue noted on a newborn's sacral area?

• A. Acrocyanosis.
• B. Mongolian spots.
• C. Erythema toxicum.
• D. Harlequin sign.

Answer: (B)

Blue-gray, flat patches in the sacral area present at birth are Mongolian spots. They come from dermal melanocytes that didn’t migrate to the epidermis during development and are common in babies with darker skin tones. These spots are benign and typically fade over time, often disappearing by early childhood. They differ from vascular or inflammatory newborn findings: acrocyanosis mainly affects the hands and feet and may blanch with pressure, Harlequin sign is a sharp, unilateral color change related to body positioning, and erythema toxicum appears as small red or yellowish bumps on the trunk and face rather than bluish pigmented patches.

Blue-gray, flat patches in the sacral area present at birth are Mongolian spots. They come from dermal melanocytes that didn’t migrate to the epidermis during development and are common in babies with darker skin tones. These spots are benign and typically fade over time, often disappearing by early childhood. They differ from vascular or inflammatory newborn findings: acrocyanosis mainly affects the hands and feet and may blanch with pressure, Harlequin sign is a sharp, unilateral color change related to body positioning, and erythema toxicum appears as small red or yellowish bumps on the trunk and face rather than bluish pigmented patches.