Amantadine-Induced Livedo Racemosa

Area of Science:

• Dermatology
• Pharmacology
• Pathology

Background:

• Livedo reticularis is a recognized adverse effect of amantadine.
• Limited research exists on the association between amantadine and livedo reticularis.
• Livedo racemosa, distinct from livedo reticularis, presents with a violaceous, netlike skin pattern and unique histopathology.

Purpose of the Study:

• To report two cases of livedo racemosa and lower extremity edema following amantadine treatment.
• To highlight the clinical and histopathological findings in amantadine-induced livedo racemosa.

Main Methods:

• Case report of two patients treated with amantadine.
• Clinical examination and documentation of skin lesions and edema.
• Histopathological analysis of cutaneous biopsies.

Main Results:

• Both patients developed livedo racemosa and lower extremity edema after amantadine initiation.
• Cutaneous biopsies revealed intraluminal thrombi in subcutaneous blood vessels.
• No evidence of vasculitis was observed in the biopsies.

Conclusions:

• Amantadine may induce livedo racemosa, characterized by vascular thrombi without vasculitis.
• This finding expands the known dermatological adverse effects of amantadine.
• Further investigation into amantadine's vascular side effects is warranted.