Last reviewed: 6 Apr 2021
Last updated: 26 Jul 2019



History and exam

Key diagnostic factors

  • nodules on shins
  • uveitis, red eyes, retinal nodules, or candle-wax drippings
  • nodules on other skin areas
  • anesthetic patches

Other diagnostic factors

  • joint pains
  • fever
  • diarrhea, constipation, abdominal pain, hematochezia
  • enlarged spleen
  • miliary nodules on the retina

Risk factors

  • streptococcal infection
  • sarcoidosis
  • tuberculosis
  • coccidioidomycosis
  • histoplasmosis
  • blastomycosis
  • brucellosis
  • Behcet disease
  • oral contraceptives
  • sulfonamides
  • iodides and antiepileptic drugs
  • psittacosis
  • leprosy
  • inflammatory bowel disease

Diagnostic investigations

1st investigations to order

  • CBC
  • antistreptolysin-O titer
  • CXR
  • purified protein derivative┬áskin testing

Investigations to consider

  • serum ACE level
  • granuloma lesion biopsy
  • coccidioidin skin test
  • histoplasmin skin test
  • lepromin skin test
  • blastomycosis serology
  • brucellosis serology
  • psittacosis serology
  • x-ray symptomatic joints
  • rheumatoid factor testing
  • Yersinia agglutination titer
  • Yersinia stool cultures
  • colonoscopy
  • serum IgD
  • deep punch biopsies including subcutaneous fat, or incisional biopsies

Treatment algorithm


Daniela Kroshinsky

Associate Professor of Dermatology

Harvard Medical School

Director of Pediatric Dermatology

Director of Inpatient Dermatology

Massachusetts General Hospital




DK declares that she has no competing interests.

Dr Daniela Kroshinsky would like to gratefully acknowledge Dr Om P. Sharma, a previous contributor to this topic. Dr Kroshinsky would also like to thank Priyanka Vedak for her contribution to this topic. OPS declares that he has no competing interests.

Peer reviewersVIEW ALL

Professor of Internal Medicine

Clinical Professor of Dermatopathology

Northeastern Ohio Universities College of Medicine


Associate Clinical Professor of Dermatology

Case Western Reserve University School of Medicine




RTB declares that he has no competing interests.

Consultant Dermatologist

King's College Hospital




EH declares that she has no competing interests.

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