Immunohistochemistry in an Adult Case of Bitot's Spots Caused by Vitamin A Deficiency.

Abstract

Bitot's spots (BS) are the buildup of superficially located keratin in the conjunctiva and are early indicators of vitamin A deficiency (VAD), primarily due to malnutrition and malabsorption, thus leading to xerophthalmia. BS are particularly prevalent in developing countries, and their presence necessitates prompt vitamin A supplementation to avert blindness, with the immunohistochemical characteristics of BS aiding in understanding the extent of epithelial abnormalities and the efficacy of vitamin A supplementation. We describe the case of a 34-year-old male with persistent BS despite extensive vitamin A supplementation and topical treatments who underwent surgical excision of the BS followed by amniotic membrane transplantation, thus resulting in symptom relief and epithelialization, with no recurrence observed during follow-up. Histopathologic and immunohistochemical evaluations revealed expression of keratinization-related proteins, along with an absence of mucin-5AC-positive cells, suggesting impaired differentiation into goblet cells due to VAD. This case highlights the potential age-related disparity in the efficacy of vitamin A supplementation, emphasizing the need for early detection and a multidisciplinary approach in the management of VAD, especially in young adults. The favorable outcome of surgical intervention highlights its viability in the management of persistent BS and encourages further investigation to optimize therapeutic strategies for VAD-related ocular manifestations.