Summary

The linear distribution of cutaneous lesions in adults is a rare but clinically valuable finding for establishing a differential diagnosis. We present the case of an adult female patient, with no relevant dermatological history, who developed a unilateral, mildly pruritic, maculopapular inflammatory erup-tion with a clear blaschkoid pattern. Clinical and paraclinical investigations, including skin biopsy, revealed a nonspecific lichenoid dermatitis without sufficient histological criteria for classification into a well-defined entity.

In this context, a diagnosis of BLAISE (Blas-chkolinear Acquired Inflammatory Skin Eruption) was considered – a recently proposed entity encom-passing acquired inflammatory dermatoses with blaschkoid distribution and variable clinical and histological features.

This case highlights the importance of recogniz-ing this emerging spectrum and maintaining a rigorous differential diagnostic approach in adult dermatology, particularly when faced with atypical presentations that do not fit traditional patterns.