ContentsSynopsisCodesLook ForDiagnostic PearlsDifferential Diagnosis & PitfallsBest TestsManagement PearlsTherapyDrug Reaction DataReferencesInformation for PatientsView all Images (67)
Erythema nodosum in Adult
Other Resources UpToDate PubMed

Erythema nodosum in Adult

Contributors: Andrew Walls MD, Susan Burgin MD, Lowell A. Goldsmith MD, MPH
Other Resources UpToDate PubMed


Erythema nodosum (EN) represents the most common type of inflammatory panniculitis (inflammation of the fat). It is an inflammatory process, typically symmetrical, and located on the pretibial region. It represents a form of hypersensitivity reaction precipitated by infection, pregnancy, medications, connective tissue disease, or malignancy. Streptococcal infections are the most common etiologic factor in children. Sarcoidosis, inflammatory bowel disease, and medications (particularly oral contraceptive pills) are more commonly implicated in adults. Often a cause or trigger is never found.

Associated bacterial, viral, fungal, and protozoal infections are numerous and include Streptococcus, Shigella, Yersinia, Histoplasma, Coccidioides, HIV, and Giardia. Tuberculosis remains an important cause in areas of endemic disease. Autoinflammatory associations include sarcoidosis, inflammatory bowel disease (eg, Crohn disease), Sjögren syndrome, reactive arthritis, Behçet syndrome, and Sweet syndrome. Malignancy, such as lymphoma, is a rare cause of EN.

The eruption typically persists for 3-6 weeks and spontaneously regresses without scarring or atrophy. Recurrences are sometimes seen, especially with reoccurrence of the precipitating factors.

Arthralgias are reported by a majority of patients, regardless of the etiology of EN. Upper respiratory tract infection or flu-like symptoms may precede or accompany the development of the eruption.

No specific genetic predilection exists except for the underlying diseases (eg, sarcoidosis is more common in individuals of African descent). EN can occur at any age, but most cases occur between the ages of 20 and 45, particularly in women.

Löfgren syndrome is a benign variant of sarcoidosis with EN and bilateral enlargement of the hilar lymph nodes. It occurs more commonly in females, especially during pregnancy.


L52 – Erythema nodosum

32861005 – Erythema nodosum

Look For

Subscription Required

Diagnostic Pearls

Subscription Required

Differential Diagnosis & Pitfalls

Other forms of panniculitis:
  • Subacute migratory panniculitis is often more focal, painless, and unilateral.
  • Nodular vasculitis / erythema induratum is typically on the posterior calves.
  • Primary infectious panniculitis occurs through septic seeding or direct inoculation of a variety of infectious organisms. Tissue culture and polymerase chain reaction (PCR) aids in diagnosis.
  • Pancreatic panniculitis favors the lower legs but is often ulcerated.
  • Lupus panniculitis favors the face and upper trunk. Most cases are not associated with systemic lupus erythematosus.
  • Panniculitis of dermatomyositis (abdomen, thighs, arms) may be the first manifestation of dermatomyositis.
Also consider:

Best Tests

Subscription Required

Management Pearls

Subscription Required


Subscription Required

Drug Reaction Data

Below is a list of drugs with literature evidence indicating an adverse association with this diagnosis. The list is continually updated through ongoing research and new medication approvals. Click on Citations to sort by number of citations or click on Medication to sort the medications alphabetically.

Subscription Required


Subscription Required

Last Updated:01/02/2022
Copyright © 2022 VisualDx®. All rights reserved.
Erythema nodosum in Adult
Erythema nodosum : Anterior lower leg, Arthralgia, Smooth plaques, Red
Clinical image of Erythema nodosum
Many erythematous and ecchymotic plaques of varying sizes on the lower legs.
Copyright © 2022 VisualDx®. All rights reserved.