Remission of photosensitivity following treatment of psoriasis vulgaris with tumour necrosis factor inhibitors

were not associated with persistent nodules or with calcification. The depth of injection of interferon appears to influence the incidence of local cutaneous reactions and consequently a longer needle has been supplied with the commercial preparation for injection. The patient described herein developed calcified necrotic subcutaneous nodules 3 years after commencing interferon beta-1a therapy and these remain palpable after 18 months. In the absence of an alternative explanation, we assume that these are a side-effect of treatment and propose that the localization on the lower abdomen reflects the preferred site of injection. Throughout therapy these lesions were asymptomatic and, in view of the previous satisfactory clinical response, subcutaneous interferon beta-1a treatment was recommenced after completion of breastfeeding as it was considered that the benefits of treatment outweighed the risk of developing further nodules. The site of injection is now rotated without preference and although transient erythema occurs at each site there are no further cutaneous adverse effects. To our knowledge this is the first report of calcified nodules as a long-term complication of subcutaneous interferon beta-1a injections.