Evaluate the Evolution of Body and Scalp Skin Discomfort in Patients With Hereditary Ichthyosis After Wraps (EnvelopIchtyose)

Ichthyosis is a group of rare and chronic genetic diseases beginning at birth, in which the patient's skin is covered with scales of variable appearance and severity. There are 2 distinct typical profiles: patients with thick scales without erythroderma and patients with finer scales on an erythrodermic background. This disease is disabling, in particular due to sensations of pruritus, skin pain and the possible presence of associated extra-cutaneous abnormalities. The treatment is symptomatic and is based on the daily application of moisturizing creams with a high lipid content for better effectiveness, keratolytic creams, and for severe forms, oral retinoids may be necessary. The creams improve the condition of the skin and reduce the sensations of skin discomfort, pain and pruritus, nevertheless, the effectiveness of these treatments is limited and are considered very painful by the patients. Wraps are local treatments carried out by specialized nurses and which consist in, following a therapeutic bath, applying a large quantity of cream to the whole body, followed by an occlusion. The type of cream is adapted to the area of application: thus, an emollient cream is used for the body; a cream enriched with keratolytic active ingredients is used for the feet in the event of hyperkeratosis, and an emollient cream possibly enriched with keratolytic active ingredients is used for the scalp, followed by an exposure time under a steam helmet to remove scales. This type of care is simple to perform, but requires nursing expertise, to date, it is not carried out in standard practice in France, except in the centers of Toulouse, Bordeaux and Necker and at the thermal cure of Avène-les-Bains. However, the interest of such a treatment has never been evaluated independently, which is why in this study the investigators want to evaluate the effect of carrying out a daily treatment over 3 consecutive days, on different parameters reflecting the skin condition in the short and medium term