Characterization of cellular infiltration in polymorphic eruption of pregnancy and pemphigoid gestationis in histopathological examinations

Background: Pregnancy-specific dermatoses represent a group of pruritic skin diseases unique to pregnancy and the most common types are polymorphic eruption of pregnancy and pemphigoid gestationis. It is difficult to obtain a histopathological diagnosis for polymorphic eruption of pregnancy and pemphigoid gestationis in the lack of immunofluorescence because of their similar clinical presentation, particularly in the absence of bullous eruptions. We assessed the potential correlation between cellular cutaneous infiltration and a diagnosis of polymorphic eruption of pregnancy or pemphigoid gestationis. Methods: This retrospective analysis was conducted at King Khalid University Hospital (Riyadh, Saudi Arabia) using biopsybased data collected from 1999–2014. The study group included 29 patients with polymorphic eruption of pregnancy and 24 patients with pemphigoid gestationis. Results: Three skin biopsy reports were excluded due to a strong history of atopy to rule out any possibility of atopic eruption of pregnancy. We performed a histopathological study of 50 patients. The data analysis revealed significant eosinophilic cell infiltration along the dermoepidermal junction and the tagging of eosinophils along the basal layer in biopsies from pemphigoid gestationis. Conclusion: We observed significant eosinophilic cell infiltration along the dermoepidermal junction and the tagging of eosinophils along the basal layer, which may support a diagnosis of pemphigoid gestationis in the absence of direct immunofluorescence.