Causes of Erythema Nodosum in Patients Admitted to a Tertiary Care Hospital in Spain.

Erythema nodosum (EN) is the most frequent panniculitis, and although it can be idiopathic, it presents multiple causal processes. We made a retrospective, observational and descriptive study about causes of EN in patients admitted to a third-level Spanish hospital over a period of 11 years, and we compared the results obtained with those published in other studies. We compared the analytical markers of inflammation between inflammatory and non-inflammatory causes of EN. The final cohort was composed by 52 patients, with 20% of idiopathic cases, 34% of cases secondary to infections and another 34% of cases secondary to autoimmune diseases. There were no cases secondary to drugs or lymphomas. We did not observe significant differences in the analytical parameters of inflammation between inflammatory or non-inflammatory cause of EN.