Prurigo Pigmentosa Associated with a Ketogenic Diet in a Romanian Patient: A Case Report

Background/Objectives: Prurigo pigmentosa (PP) is a rare inflammatory dermatosis characterized by recurrent pruritic eruptions resolving with reticulated hyperpigmentation. Initially described in young Asian women, PP is increasingly reported worldwide, often linked to ketosis-inducing factors such as low-carbohydrate diets. This report documents the first case of PP in a Romanian patient and highlights the importance of recognizing the condition in diverse populations. Methods: We describe a 16-year-old girl with a six-month history of pruritic eruptions on the neck, trunk, shoulders, and thighs. A detailed clinical assessment was conducted, including dietary history, physical examination, laboratory evaluation of urinary ketones, and skin biopsy for histopathological analysis. Results: Clinical examination revealed erythematous papules and plaques with peripheral pustules and post-inflammatory hyperpigmentation. Substantial weight loss and elevated urinary ketone levels suggested dietary-induced ketosis from a strict low-carbohydrate diet. Histopathological findings confirmed the diagnosis of PP. The patient's skin lesions resolved following carbohydrate reintroduction and doxycycline therapy. Conclusions: This case highlights the association between ketosis and PP, emphasizing the importance of thorough dietary history-taking and histopathological confirmation for accurate diagnosis. As ketogenic diets become more popular globally, heightened awareness of PP is essential to ensure timely diagnosis and effective management.