Vitamin D Deficiency After Oral Retinoid Therapy for Ichthyosis.

Oral retinoids are being increasingly used to treat ichthyotic disorders in children. We report on two children with ichthyotic disorders who developed unusual manifestations after they were started on oral retinoids. The first case is a 10-year-old girl with nonbullous ichthyosiform erythroderma and the second is a 2-year-old girl with lamellar ichthyosis. The child with ichthyosiform erythroderma developed features of rickets within months of initiation of systemic retinoids. Her baseline examination before initiation of oral retinoids was normal. The second patient with lamellar ichthyosis was found to have low vitamin D levels after 6 months of retinoid therapy, and prompt supplementation reversed the levels in 2 months. These cases are being reported to bring attention to the probable need for initiation of vitamin D supplementation with systemic retinoid therapy in ichthyotic disorders in children.