Volume 184 - Issue 6
Erythema induratum: a case of mistaken identity
Authors: Gary Y Chew, Christopher Henderson and John W Quin
Med J Aust 2006; 184 (6): 306-307. || doi: 10.5694/j.1326-5377.2006.tb00247.x
Published online: 20 March 2006
Published online: 20 March 2006
Gary Y Chew,* Christopher Henderson,† John W Quin‡
* Registrar, ‡ Director of Clinical Immunology, Department of Immunology, Liverpool Hospital, Bigge Park Centre, PO Box 103, Liverpool, NSW 2170; † Anatomical Pathologist, South Western Sydney Area Health Service, Liverpool, NSW.
In reply: We thank Bennett and Muir for their pertinent comments. Our patient did not have any history or clinical evidence of lepromatous leprosy. The skin biopsy did not reveal any dermal granulomatous involvement, and there were definitely no organisms seen on an auramine stain of the biopsy specimen.
Subcutaneous involvement in leprosy is uncommon except in erythema nodosum leprosum or as a neurotropic phenomenon. When present, it tends to be a neutrophil-rich hypersensitivity necrotising vasculitis — no features of which were seen in this case. Neither the woman’s partner nor child had a chronic skin condition or clinical history of leprosy or tuberculosis. Furthermore, the patient has been followed up for 12 months, with no recurrence of the rash.
We agree with Muir that an accurate diagnosis is crucial to managing any skin disease and that there were many lessons to be gathered from this case apart from the five points we listed. It is our usual practice not to begin definitive treatment until we have examined a skin biopsy of any suspicious lesion and made a diagnosis. As this patient was very concerned about getting a scar, we did not perform a skin biopsy initially, but informed her that we may need to do so if the condition did not respond to treatment.
We agree that patients from areas where tuberculosis is endemic should have tuberculosis excluded before instituting systemic steroid treatment. In this case, the patient was given a chest x-ray by the appropriate authorities before her migration to Australia. She has not returned to Vietnam since then. Furthermore, the patient had failed a trial of a non-steroidal anti-inflammatory drug and found the lesions cosmetically distressing. Consequently corticosteroids were instituted.