A 72 year old female patient had a 30 year history of progressive rheumatoid arthritis treated ultimately with a combination of ciclosporin A plus corticosteroids and anti-inflammatory agents. Adalimumab was started as anti-tumour necrosis factor (TNF) monotherapy because the disease persisted. Ciclosporin A was discontinued 3 months before the initiation of adalimumab. At the site of the first adalimumab injection, a mild local reaction developed 6–8 hours later, not accompanied by general symptoms.

Three to 4 hours after the second adalimumab injection (15 days later), the patient presented at the emergency department with chest discomfort, epigastralgia, fever (38.4°C), rigor, fatigue, and malaise. At the same time, at the injection site (left thigh), a violaceous plaque (10×9 cm) had developed, emerging as an erythematous urticarial oedema (fig 1A). Laboratory investigation …