Frozen section is a valuable tool that is often underutilized in the setting of in-patient dermatology. Traditionally, frozen section has been used in dermatology to diagnose toxic epidermal necrolysis, with some additional utility in staphylococcal scalded skin syndrome in the new born period. We report a newborn female with ruptured bullae on the face, chest, back and extremities with a clinical differential diagnosis that included staphylococcal scalded skin, bullous congenital ichthyosiform erythroderma/epidermolytic hyperkeratosis and epidermolysis bullosa. A thin detached skin sample (\'jelly-roll\') taken from a ruptured bulla on the abdomen was prepared for frozen section analysis. Characteristic findings of epidermolytic hyperkeratosis were seen which included hyperkeratosis with granular layer degeneration, vacuolization and eosinophilic globules. The \'jelly-roll\' technique can be used for quick diagnosis with minimal trauma to the patient. Epidermolytic hyperkeratosis was subsequently confirmed by a biopsy fixed in formalin and by genetic testing. A novel missense mutation in KRT1 (I479N) was identified. Herein, we discuss the use of the frozen section \'jelly roll\' technique for rapid diagnosis in a case of bullous congenital ichthyosis erythroderma/epidermolytic hyperkeratosis.

Epidermolytic ichthyosis (EI) is a rare skin disorder characterized by generalized erythroderma and cutaneous blistering at birth, which is substituted by hyperkeratosis later in life. It is caused by autosomal dominant mutations in highly conserved regions of KRT1 and KRT10. To date, only 4 mutations with autosomal recessive inheritance of EI have been described in consanguineous families. All of them affect the 2B domain of KRT10. In the present study we describe four patients with EI (including one lethal case) born from unaffected parents in a consanguineous family of a native Venezuelan community. The objective of this study was to characterize the clinical, genetic and morphological aspects of the disease in this family, as well as understand its functional implications. Genomic DNA was sequenced for KRT10 and KRT1. Immunofluoresence for keratin expression was performed on cutaneous biopsies. After examination of cutaneous biopsies histology, our results showed hyperkeratosis and acantholysis with an expanded granular layer. Sequencing of KRT10 demonstrated a non-sense mutation (p.Tyr282Ter.) corresponding to the 1B domain of the protein in patients and a heterozygous pattern in other family members, resulting in complete absence of K10. The loss of K10 was compensated by upregulation of K14 and K17. In conclusion, this novel mutation in KRT10 is the first recessive genetic variation that is not located in the so called \"hot spot\" for recessive EI, suggesting that other areas of the gene are also susceptible for such mutations.