1. ichthyosis occurs when scales are polygonal or diamond-shaped, with the center attached, the edge inclined, the back and limbs stretched, and the chest, abdomen and limbs flexed, which can occur, with childhood onset, adolescent aggravation, and heavy winter and light summer.

2, chicken skin generally only appears dry dander around the keratinized hair follicle in winter aggravation period, and the dander is generally small, which is caused by the accumulation of keratinized dryness around the hair follicle mouth, which occurs on the outer arm and the extended thigh side.

3, ichthyosis skin is accompanied by hair follicle keratinization papules, when it is light, it looks like pores are thicker, each pore is a small point, and it feels rough by hand. In severe cases, these points will become obvious. If they appear together, they will look like a file.

4. The skin lesion of chicken is the phenomenon of protein accumulation in the mouth corner of hair follicle. In severe cases, there will be redness or swelling around. Pores will be darker, dark red or brown, and particles will be coarser and look like goose bumps.

5. Patients with ichthyosis generally have no itching symptoms, and itching only occurs when sudden symptoms worsen; The skin lesions of chicken skin patients are often accompanied by itching.