Mi-Ran Kim, Vinzenz Oji, Frederic Valentin, Heiko Traupe, Jerzy-Roch Nofer, Ingrid Hausser, Hans Christian Hennies, Katja Eckl, Stefan A. Wudy, Alberto Sánchez-Guijo, Laura Kerschke, Judith Fischer, Kira Süßmuth
DOI: 10.2340/00015555-3887

Data on vitamin D status of patients with inherited ichthyosis in Europe is scarce and unspecific concerning the genetic subtype. This study determined serum levels of 25-hydroxyvitamin D3 (25(OH)D3) in 87 patients with ichthyosis; 69 patients were additionally analysed for parathyroid hormone. Vitamin D deficiency was pronounced in keratinopathic ichthyosis (n = 17; median 25(OH)D3: 10.5 ng/ml), harlequin ichthyosis (n = 2;7.0 ng/ml) and rare syndromic subtypes (n = 3; 7.0 ng/ml). Vitamin D levels were reduced in TG1-proficient lamellar ichthyosis (n = 15; 8.9 ng/ml), TG1-deficient lamellar ichthyosis (n = 12; 11.7 ng/ml), congenital ichthyosiform erythroderma (n = 13; 12.4 ng/ml), Netherton syndrome (n = 7; 10.7 ng/ml) and X-linked ichthyosis (n = 8; 13.9 ng/ml). In ichthyosis vulgaris 25(OH)D3 levels were higher (n = 10; 19.7 ng/ml). Parathyroid hormone was elevated in 12 patients. Low 25(OH)D3 levels were associated with high severity of scaling (p = 0.03) implicating scaling as a risk factor for vitamin D deficiency. Thus, this study supports our recent guidelines for ichthyoses, which recommend screening for and substituting of vitamin D deficiency.

This study collected clinical data for 87 patients with inherited ichthyoses, and analysed serum levels of 25-hydroxyvitamin D3 (25(OH)D3) and parathyroid hormone. These measurements were performed before routine substitution of vitamin D in ichthyoses. Vitamin D deficiency and insufficiency was highly prevalent in this study cohort. Less than 10% of the patients had sufficient vitamin D levels. Moreover, vitamin D deficiency was related to the clinical severity of scaling. Thus, this study supports our recent guidelines for ichthyoses, which recommend screening for and substituting of vitamin D deficiency.

Table SI
Figure S1