Ichthyosis Vulgaris

Group of cutaneous disorders of keratinization representing more than 95% of ichthyosis cases. Can be a genetic disorder that is generally present soon after birth, or it can be a nonhereditary condition associated with internal disease, such as malignancies, or it can be induced by various medications. Most patients present with asthma, eczema, and fever.

(Figure)

(Figure)

Ichthyosis Simplex.

Autosomal dominant inheritance.

Hereditary forms can be caused by altered profilaggrin expression leading to scaling and desquamation and is often associated with atopy. It is a retention hyperkeratosis; expression of profilaggrin is absent or reduced in the epidermis.

At birth, skin is normal. It gradually becomes rough and dry in early childhood. Scaling tends to be most prominent on the extensor surfaces of the extremities and absent on the flexor surfaces. Lesions are rare in the axillae and antecubital and popliteal fossae. Forehead and cheeks may be involved, but lesions in these areas diminish with age. Notable amelioration in summer.

Features involve mainly skin with scales (fine, irregular, and polygonal in shape) of various sizes and colors. Lower extremities generally are more affected than the upper extremities. The face is generally spared however, hyperkeratosis of the palms and soles and follicular hyperkeratosis of the cheek and neck is often present. Pruritus is frequent. Fissures can appear with secondary infections. Inflammation is possible.

Evaluate hydration status in case of extensive ichthyosis.

Fixation of monitoring devices and indwelling catheters on skin can be difficult. There is an increased risk of superinfection following installation of venous puncture, regional anesthesia, and any other maneuvers leading to skin damage. Patients affected are susceptible to thermoregulatory imbalance leading rapidly to severe hypothermia.

Nicotinic acid, triparanol, butyrophenones, dixyrazine, cimetidine, and clofazimine have been implicated in acquired ichthyosis and should be avoided. Consider the administration of steroid stress doses in case of long-term treatment.

Multiple forms of ichthyosis.