Adalimumab causing vasculitis

Extract

Conflicts of interest: none declared.

Sir, Targeting specific cytokines in the treatment of autoimmune inflammatory conditions continues to increase in prevalence. The products aimed at inhibiting tumour necrosis factor (TNF)‐α include infliximab, etanercept and, more recently, adalimumab.

We report a 44‐year‐old Indian woman who had recently been commenced on adalimumab (Humira^®; Abbott Laboratories, Maidenhead, U.K.) for rheumatoid arthritis (RA). She had a 16‐year history of polyarthropathy with positive rheumatoid serology. Over this time she had received numerous disease‐modifying antirheumatic drugs including sulfasalazine, ciclosporin and methotrexate, with only modest success. In the previous year she had taken etanercept, but this produced no significant therapeutic response; her only other medication was prednisone 5 mg daily.

Within 24 h of administration of her second dose of adalimumab (40 mg by subcutaneous injection 2 weeks after the first) she developed an intensely pruritic eruption on the dorsal aspect of her feet and around both medial malleoli. The following day the rash had faded somewhat but consisted of nonblanching palpable purpuric/erythematous papules symmetrically distributed over both feet (Fig. 1). Clinically, the eruption appeared to be vasculitic. An incisional biopsy was taken from the right medial ankle and specimens sent for histopathology and direct immunofluorescence. Within 5 days of the rash appearing it had subsided completely.