[Cutaneous ulcer as the initial manifestation of rheumatoid arthritis. Case report].

Background: 20-40% of patients with rheumatoid arthritis (RA) present an extra-articular manifestation (EAM) and 1-20% a severe EAM, with an increased risk of death (> 2 times). The associated lesions are: 27.5% rheumatoid nodules, and 0.5% neutrophilic dermatitis, palisaded neutrophilic granulomatous dermatitis, and/or cutaneous vasculitis. Clinical case: 52-year-old woman who suddenly presented with a painful skin ulcer on the dorsum of the left foot with violaceous, well-defined, raised edges and granulation tissue with fibrinopurulent membranes, with an edematous halo, and subsequent crusting and perilesional hyperpigmentation. The lesion did not show improvement despite debridement and antibiotics. Biopsy with abundant neutrophils in the dermis and vasculitis was reported. Paraclinical testing showed: C-reactive protein: 32.5 mg/dL, erythrocyte sedimentation rate: 59 mm/h, and rheumatoid factor (RF): 2460 U/mL, in addition to antinuclear antibodies (1:640), negative anti-DNA, and anti-citrullinated protein/peptide antibodies (ACPA/anti-CCP) positive (221.70 U/mL), confirming the diagnosis of RA. Conclusions: Rheumatoid vasculitis is the most serious EAM of RA, with more than 40% of patients dying 5 years after clinical onset. It is a rare complication and more common in men with longstanding RA. We highlight the importance of suspecting autoimmune pathology, especially RA, in the presence of spontaneous skin ulcers, without an infectious component and with alterations in the basic laboratory tests.