Summary

Introduction: Neurofibromatosis type 1 (NF1) is a common autosomal dominant disorder characterized by cutaneous neurofibromas, café-au-lait spots, and potential systemic involvement. Patients with NF1 may also develop unrelated dermatological conditions, which can pose diagnostic challenges. In this report, we describe the case of a patient with a known history of NF1 who presented with new inflammatory skin lesions, highlighting the importance of differential diagnosis in patients with pre-existing complex skin disorders.

Case presentation: We present the case of a 51-year-old male patient, previously diagnosed with neurofibromatosis type 1, who was admitted to our dermatology clinic for evaluation of erythematous, violaceous, scaly plaques located bilaterally in the pretibial region. The patient reported the recent onset of pruritic lesions without systemic symptoms. Clinical examination and laboratory investigations, including inflammatory markers and liver function tests, were performed. A clinical diagnosis of pretibial lichen planus was established based on the morphology and distribution of the lesions. No signs of neurofibromatosis-related complications were identified during hospitalization. The patient received topical corticosteroid therapy and antihistaminic receptor antagonists, with favorable evolution, and was advised regular dermatological follow-up.

Conclusions: In patients with pre-existing complex dermatological conditions such as NF1, the development of new skin lesions necessitates thorough clinical evaluation to distinguish between disease-related manifestations and unrelated dermatological entities. Early recognition and appropriate treatment of conditions like lichen planus can significantly improve patient outcomes.