Background: Endemic pemphigus foliaceus and endemic pemphigus vulgaris are autoimmune dermatologic disorders endemic to the Peruvian Amazon. Objective: To determine the ultrastructural skin alterations of three healthy subjects with anti DSG-1 antibodies in areas endemic to pemphigus foliaceus and pemphigus vulgaris in the Peruvian Amazon. Patients and methods: Case series carried out from data of three clinically healthy subjects positive to anti DSG-1 antibodies, from Peru. This study consists of a sub-analysis of data gathered in a previous study. Results: Ultrastructural results are presented from the skin biopsies of three clinically healthy patients positive to anti-desmoglein 1 (DSG-1) antibodies. High Resolution Optical Microscopy (HROM) showed the absence of acantholysis. Transmission Electron Microscopy (TEM) showed the widening of intercellular space between keratinocytes, the presence of vacuoles in intercellular space with granular material and cytoplasmic vacuolization, loss of desmosome structure, loss of normal distribution among tonofilaments and lateral separation among cells in the stratum basale. Conclusion: According to our results, healthy subjects that present anti-desmoglein 1 antibodies can develop ultrastructural alterations that are visible through transmission electron microscopy but not through conventional optical microscopy. © 2023