Nicolau syndrome due to self-injectable drugs in multiple sclerosis

Abstract

Nicolau syndrome, or embolia cutis medicamentosa, is a rare cutaneous complication of drug injection that has been rarely described in relation to medication used in multiple sclerosis. We conducted a retrospective study of patients with Nicolau syndrome receiving self-injectable multiple sclerosis medication from 2010 to October 2022. From January 2010 to October 2022, 449 patients were followed up in our demyelinating pathology unit with self-injectable drugs - 317 with beta interferons and 132 with glatiramer acetate (GA). In this period of time, 10 episodes of Nicolau syndrome were recorded in seven patients (six men and one woman) receiving GA, which represents 5.3% of the total number of patients receiving this treatment. The most commonly affected areas were the buttocks (n = 4) and the arms (n = 3). Three patients (42.8%) suffered a second episode. Nicolau syndrome is a complication unique to GA and more frequent in men in our cohort of multiple sclerosis patients. This cutaneous complication frequently recurs in the same patient, which is a factor to be taken into account in the decision to maintain the drug or switch to another therapeutic strategy.