Erythema elevatum diutinum in Crohn's disease-associated Spondyloarthritis - a rare vasculitis, an unusual association.

Erythema elevatum diutinum is a rare neutrophilic dermatoses with vasculitis, which presents as persistent, symmetrical, purple or brownish papules and nodules, mainly in the extensor surface of the limbs. We describe a case of erythema elevatum diutinum and polyarthritis as initial manifestations of Crohn's disease associated spondyloarthritis. A 51-year-old man, from São Tomé e Príncipe, with previous history of treated tuberculosis and chronic hepatitis B infection, was admitted due to 4 months history of polyarthritis, hyperpigmented papules on the extensor surfaces, occasional episodes of bloody mucous diarrhea and significant weight loss. Histology of the skin showed neutrophilic granulocytes with marked fibrosis and moderate karyorrhexis, consistent with erythema elevatum diutinum. Colonoscopy showed erosions in sigmoid and rectum. Diagnosis of erythema elevatum diutinum secondary to Crohn's disease with associated peripheral spondyloarthritis was assumed. The patient was treated with prednisolone, sulphasalazine, metronidazole, azathioprine and tenofovir with good clinical response. As erythema elevatum diutinum can be secondary to multiple systemic diseases, including rheumatic diseases and inflammatory bowel disease, being aware and recognizing this entity can be of great importance for rheumatologists.