A Case of Erythema Nodosum in a 20-Year-Old Female During the Postpartum Period.

Erythema nodosum (EN) is the most common form of panniculitis and occurs in about one in 100,000 people. EN typically presents as an eruption of tender, erythematous nodules on the anterior aspect of the legs, although the face, trunk, and arms can also be involved. While the majority of cases are idiopathic, a subset of cases occurs in association with various triggers, including infections, medications, tumors, and autoimmune diseases. Rarely can EN develop in relation to pregnancy, which is thought to provide a physiologic background that favors its development. While pregnancy has been associated with EN in a minority of cases, currently, there is a limited amount of data suggesting that EN can develop in the late postpartum period. Herein, we present a case of a 20-year-old female with a six-week history of painful lesions on her lower extremities. A physical exam revealed multiple tender, erythematous nodules on the anterior aspect of the lower extremities, spanning from the knees to the toes. Laboratory workup showed no other identified triggers of EN in our patient besides pregnancy. Management of EN in our patient involved a low dose, six-day course of prednisone (initial dose of 15 mg/day) and ibuprofen for one week, leading to symptomatic improvement. Our case emphasizes the possibility of EN presenting in the late postpartum period. This case underscores the importance of considering EN in the differential diagnoses for women presenting with compatible lesions postpartum.