Psoriasis may often appear in the nappy region in infancy and in flexural areas in children. Acute episodes of plaque psoriasis may evolve into more severe disease – eg, pustular or erythrodermic psoriasis. Cutaneous T-cell lymphoma (consider where a rash is not responding to optimal treatment or if there is colour variation between plaques). Plaque psoriasis is one of the most common forms. If you develop a rash that doesn’t go away with an over-the-counter medication, you should consider contacting your doctor. What about psoriasis in children? Many people have another type of psoriasis elsewhere on the body at the same time. Symptoms include pitting and discoloration of the nails, severe scalp scaling, diaper dermatitis or plaques similar to that of adult psoriasis on the trunk and extremities. Other exacerbating factors include trauma or irritation of the skin and the use of certain medications such as lithium, -adrenergic antagonists and tumor necrosis factor alpha (TNF- ) inhibitors in children with Crohn’s disease or juvenile idiopathic arthritis (JIA) 18 20. Psoriatic diaper rash is seen in young infants and is characterized by sharply demarcated, minimally elevated erythematous plaques in the diaper area, involving the inguinal folds. Guttate psoriasis is the second most common type of psoriasis in children 21, 29.
Plaque and guttate psoriasis are the most common morphologies observed in children. In children younger than 2 years of age, psoriatic diaper rash is a common presentation (see also Chapter 17). 12,13 Neonatal erythrodermic psoriasis has overlapping features with primary immunodeficiency syndromes, Netherton syndrome, metabolic disorders, systemic infections, and certain forms of ichthyosis.