Spot diagnosis

This 39 year-old woman presented with an erythematous nodular rash on her lower legs.

A chest X-ray was obtained and hilar lymphadenopathy was discovered.

This is Lofgren Syndrome, or acute sarcoidosis, which is the manifestation of sarcoidosis, a rare syndrome characterised by erythema nodosum, hilar adenopathy, fever and migratory polyarthritis.