A salutary case of Fumaderm�potentially masking the symptoms of bowel cancer and partial bowel obstruction

Abstract

Conflicts of interest: none declared. Sir, We present a patient who was started on Fumaderm® (dimethylfumarate + monoethylfumarate Ca, Mg and Zn salts; Fumedica, Herne, Germany) for treatment of his chronic plaque psoriasis. The side‐effect profile of Fumaderm® is good with mainly flushing, gastrointestinal upset in the form of bloating and a relative lymphocytopenia. Our case highlights how the common adverse events of gastrointestinal upset, namely abdominal pain and cramps, diarrhoea, nausea and bloating, can effectively disguise the similar symptoms of co‐existent bowel cancer and partial bowel obstruction. Our patient experienced all these gastrointestinal symptoms typified by the side‐effects associated with Fumaderm® therapy. They were automatically and erroneously attributed to be due to Fumaderm® and it was only on the development of a microcytic anaemia and investigation into a gastrointestinal cause for this that a metastatic bowel cancer with imminent bowel obstruction was identified. Our case serves as an invaluable caveat for all dermatologists who routinely prescribe Fumaderm® in their practice that the persistence of gastrointestinal symptoms while on Fumaderm® may well herald a more sinister aetiology warranting and justifying prompt investigation.