A young woman presents with a nodular rash seen on her legs bilaterally and chest X-ray showing hilar lymphadenopathy. This is a diagnosis of Löfgren syndrome, named after a Swedish clinician, Sven Löfgren . It is a type of acute sarcoidosis that can manifest with arthritis, erythema nodosum as seen above on the right and hilar lymphadenopathy. Sarcoidosis itself is characterized by the development of non-caseating granulomas in different organs, predominantly in lymph nodes and lungs. This form of sarcoidosis carries an excellent prognosis with >90% of patients having symptom resolution within 24 months. The mainstay therapy is usually NSAIDs.
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