Despite their variable etiopathologies, all forms of dermatitis show similar histopathologic just as similar dermoscopic characteristics. Dermatitis usually exhibits red dots in a patchy distribution and yellow scales. The red dots are identical to the vessels in psoriatic lesions, but unlike psoriasis, their distribution is not homogenous and regular, but rather clustered, generating an irregular, “patchy” pattern. Superficial scaling is a frequent characteristic of dermatitis, but opposed to psoriasis and other erythematosquamous skin diseases, the scales in dermoscopy of dermatitis reveal a yellow color either alone, or in combination with white.  Belonging to the group of the characteristic yellow scales, the “yellow clod sign” is frequently observed in nummular eczema. Notably, yellow scale color is dermoscopically detected not only in acute, but also in chronic dermatitis. Contact dermatitis, nummular eczema, generalized dermatitis, chronic dermatitis, seborrheic dermatitis and other subtypes were reported to reveal similar findings in dermoscopy, but further investigation on their specific pattern is needed.
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