Congenital ichthyosiform erythroderma: particulate staining pattern of TGK.
A case of late onset non-bullous congenital ichthyosiform erythroderma (CIE) was studied. This patient was not born as a collodion baby and did not have skin abnormalities until 9-10 years of age. She gradually developed erythroderma and fine scales, callosities of her feet, and a mild ectropion. Since recent work has revealed that in the majority of CIE patients, transglutaminase (TGK) is distributed in the cytoplasm of granular cells and horny cells (11), TGK was studied in our case. It was found that TGK was distributed along the cell periphery of horny cells and also in the cytoplasm of granular cells. In the control skins, TGK was stained along the cell periphery of horny cells and granular cells. The marginal band formation was normal. Involucrine and loricrin, the building materials of the marginal band whose-cross-linking is mediated by TGK, were normally stained in the upper epidermis. Cytoplasmic TGK of granular cells and normal development of the marginal band may serve as a helpful diagnostic marker of CIE, particularly because the often confusing collodion baby of lamellar ichthyosis may lack TGK staining and the marginal band altogether.