Erythema induratum of Bazin and Ponçet's arthropathy as epiphenomena of hepatic tuberculosis.

A 42-year-old black woman presented with fever, polyarthritis, livedo reticularis, subcutaneous calf nodules and hepatomegaly. She had been diagnosed with depression 6 weeks prior. Blood analysis showed anaemia, elevated erythrocyte sedimentation rate and C reactive protein, elevated liver enzymes, and positive antinuclear and antiribonucleoprotein antibodies. Abdominal ultrasound revealed heterogeneous hepatomegaly with necrotic lymphadenopathy around the caeliac trunk and splenic hilum. We considered the following diagnoses: lymphoma, connective tissue disease, tuberculosis and sarcoidosis. Subcutaneous nodule histology was compatible with erythema induratum of Bazin, and liver biopsy evidenced granulomatous hepatitis. Although microbiological examinations were negative in tissue samples, a presumptive diagnosis of hepatic tuberculosis was admitted. Having excluded other causes, erythema of Bazin, livedo reticularis and polyarticular involvement (Ponçet's arthropathy) were accepted as immunological epiphenomena associated with tuberculosis. Empirical antituberculous treatment was started and after 3 weeks the patient improved substantially. This clinical response was a further confirmation of the diagnosis. 2016 BMJ Publishing Group Ltd.