Reflectance Confocal Microscopy Of A Preliminary Study In Verrucous Epidermal Nevus

Background Verrucous epidermal nevi(VEN)are congenital hamartomas composed of keratinocytes and may occur alone or in association with developmental abnormalities.It usually presents at birth or occurring within the first years of life.The keratinocytes arise from pluripotential germ cells in the basal layer of the embryonic ectoderm and results from mosaic postzygotic mutations.VEN follows the lines of Blaschko and usually presents as hyperpigmented papilloma-like papules and plaques,and is divided into localized,systematized and inflammatory linear verrucous epidermal nevus(ILVEN).The diagnosis is usually based on clinical presentation and histopathology examination.It is mainly divided into non-inflammatory and inflammatory in histopathology.Reflectance confocal microscopy(RCM)is noninvasive,high-resolution imaging tool for the histological evaluation of the skin in vivo.According to the relevant literatures,it is found that the RCM imaging characteristics of VEN have not been systematically analyzed.This study intends to observe RCM features of VEN and clarify these features to help achieve noninvasive diagnosis of VEN.Object Reflectance confocal microscopy features of verrucous epidermal nevus have rarely been investigated.The aim is to determine the features of verrucous epidermal nevus in RCM and analysis the significance of RCM in the diagnosis of VEN,provide a basis for non-invasive diagnosis of verrucous epidermal nevus.Methods The study included the patients with histopathologically approved verrucous epidermal nevus or agreed to perform histopathology.We completed clinical data collection,RCM imaging collection and histopathology collection.We selected 33 patients with histopathologically approved VEN.Clinical,RCM,and histopathological features of the patients were retrospectively reviewed and the findings identified were recorded.It was classified localized,systematized and ILVEN by clinical presentation,and was divided into non-inflammatory and inflammatory by histopathology.Results Of the 33 patients,13 were male and 20 were female,age ranged from 2 to 37 years,with an average age of 8.82 years,no family history,it is finded 15 cases at birth,13 cases at 1 to 6 months,4 people at 7 to 12 months,and 1 case is not clear.The skin lesions first appeared 8 cases in the head and neck,3 in the trunk,6 in the upper limbs,13 in the lower limbs,and 3 in the buttock.There are 2 localized patients,21 with generalized patients,including 10 with unilaterally generalized patients,11 with bilaterally generalized patients,and 10 with inflammatory linear epidermal nevus.The histological examination showed hyperkeratosis,acanthosis,papillomatosis,acanthosis,elongation of reteridge and superficial perivascular infiltration of lymphocytes in the dermis about non-inflammatory VEN and Hyperkeratosis,granule degeneration,acanthosis,papillary hyperplasia,cutaneous prolongation and superficial perivascular infiltration of lymphocytes in the dermis about ILVEN.Of these 33 VEN lesions,there were 31 of hyperkeratosis(93.94%),28 of papillomatosis(84.85%),26 of hyperpigmentation of the basement layer(78.79%),23 of apophysis prolonged(69.70%),26 of vasodilation(78.79%),17 of inflammatory cells infiltration(51.52%),2 of parakeratosis(6.06%)and 1 of dyskeratosis(3.03%).Conclusions The main microscopic characteristics of VEN were observed in real time.These features include hyperkeratosis,papillomatosis,hyperpigmentation of the basement layer,apophysis prolonged,vasodilation,inflammatory cells infiltration,parakeratosis and dyskeratosis.These have obvious correlation with histopathology,RCM is a tool for the noninvasive diagnosis of VEN.