Follicular parakeratosis (Congenital hemidysplasia with ichthyosiform nevus and limb defects (CHILD)) is a genetic skin disease of Rottweiler and Siberian Husky dogs. This disease primarily affects skin follicles and results in thickened stratum cornea with abnormal waves of keratin lining.
Affected dogs present with a generalized skin condition with thickened areas of dry, scaly skin on the face, ears and trunk, however it does not affect the nose and paws. Affected dogs will not be itchy but will have a dull, greasy coat with excessively flaking skin.
Histologically, this condition appears as marked parakeratosis targeting the hair follicle and numerous intracorneal vacuoles.
A differential diagnosis would include ichthyosis, distemper, trauma (constant rubbing against hard surfaces), lupus erythematosus, Malassezia spp and Aspergillus spp dermatitis, localized ringworm, idiopathic seborrhoea, necrolytic migratory erythema, zinc-responsive dermatosis, thallotoxicosis and nasal parakeratosis (Labrador Retriever).
There is no specific treatment for this condition, although emollient anti-seborrheic shampoos may alleviate clinical symptoms.