Abdominal wall ulceration and mucinosis secondary to recombinant human interferon-beta-1b.

46-year-old woman developed painful ulcers over her lower abdomen in the form of reticulate erythema after injecting interferon beta-1b subcutaneously for multiple sclerosis. Skin biopsy revealed multiple superficial thrombosed vessels with focal epidermal necrosis as well as prominent interstitial mucinosis. Treatment with low-molecular-weight heparin followed by a heparinoid resulted in slow healing of the ulcers but also allowed the subcutaneous interferon injections to be continued.