Erythema nodosum leads to the diagnosis of pulmonary tuberculosis.

Erythema nodosum is a panniculitis which may have various causes, such as drugs, infections, sarcoidosis, inflammatory bowel disease, tuberculosis or can be idiopathic. We here report a case of a woman diagnosed with pulmonary tuberculosis whose first symptom was erythema nodosum. A thorough clinical and laboratory investigation of the patient presenting with erythema nodosum is always required, in order to assess a possible systemic, underlying condition.