[Nicolau syndrome after administration of glatiramer acetate].

Local complications associated with glatiramer acetate are frequent, especially at the injection site. The presence of pain, oedema, and local erythema is almost a given in areas where the drug is administered subcutaneously. However, the presence of cutaneous necrosis should alert doctors to the possibility of impairment of underlying vascular structures. Nicolau syndrome or embolia cutis medicamentosa is an uncommon complication resulting from the intramuscular, intra-articular or, more rarely, subcutaneous administration of some drugs. Symptoms include cutaneous infarction due to damage to nearby small and medium-sized hypodermaldermal vessels. There are several documented cases involving administration of different drugs or vaccines. We present the case of a 45-year-old woman who developed painful cutaneous lesions following subcutaneous injection of glatiramer acetate. Following diagnosis with relapsing-remitting multiple sclerosis, she had been treated with glatiramer acetate (20 mg/day) for 3 years. She was referred to the dermatology department due to the appearance of localised painful lesions in the lateral left thigh. Symptoms had begun to appear 7 days previously, after subcutaneous administration of the drug to this area. The patient’s personal and family history did not reveal relevant findings. The examination revealed a purplish plaque with a hardened, infiltrative feel with no other relevant cutaneous or systemic findings (Figs. 1 and 2). A blood test showed haematological, haemostatic, and biochemical parameters within normal ranges. The blood test showed no autoimmune markers (ANAs, ANCAs, anti-DNA, anti-Ro, anti-La) and no lupus anticoagulants or cryoglobulins. The histopathological study of the lesion revealed coagulative necrosis of dermal collagen and nearby adipose tissue, as well as multiple hyaline thrombi inside small and medium-sized blood vessels. These were located throughout the dermis and hypodermis with no apparent perivascular inflammatory component. The study found no calcium deposits in vascular walls, no cholesterol crystals, and no intravascular fungal matter. A soft tissue ultrasound showed no damage to underlying muscular tissue. Given a diagnosis of Nicolau syndrome, doctors decided to continue injecting treatment in other sites while closely monitoring the lesions. The patient’s cutaneous symptoms progressively improved; by 4 weeks, a depressed scar had formed in the lateral thigh. The presence of retiform purpura (purpuric macules in a web-like pattern) is a fundamental clinical sign of