Internal Medicine

P1: OXT/OZN/JDO P2: PSB

0521779407-E-01 CUNY1086/Karliner 0 521 77940 7 June 4, 2007 21:10

Erythema Nodosum 549

Signs & Symptoms

■Bilateral, red, tender nodules on the anterior shins

■Other sites: upper legs, extensor aspects of arms, and neck

■Lesions slowly flatten, leaving purple or blue-green color resembling

a bruise

■Often accompanied by fever, chills, malaise, arthritis or arthralgia,

and leukocytosis

■Usually resolves spontaneously in 3 to 6 weeks

tests

■Blood: Elevated ESR is common

➣CBC indicated in all patients

■Imaging: CXR to rule out sarcoidosis

Other Tests

■Deep skin biopsy including the subcutaneous fat is needed only

when the diagnosis is in question or the patient has a recurrent or

chronic course.

■Search for underlying disease: based on geographic location, age,

history, and physical; a throat culture, ASO (Streptozyme) titer, bac-

teriologic, virologic or Yersinia titer, and tuberculin or fungal antigen

skin test

Diagnosis: Based on typical clinical appearance and biopsy

differential diagnosis

■other forms of panniculitis

➣erythema induratum – often on the posterior calf

➣subcutaneous fat necrosis associated with pancreatitis – associ-

ated abdominal pain

■syphilitic gumma

■nodular vasculitis

management

What to Do First

■Assess the patient for underlying disease.

■Any underlying abnormality should be treated.

■Bed rest, elevation, support hose for mild cases

specific therapy

■Aspirin, NSAIDS often helpful

■Potassium iodide is frequently effective.

■Intralesional injection of triamcinolone acetonide