A retrospective study of the severe and uncommon variants of erythema nodosum leprosum at a tertiary health center in central India.

Background: Erythema nodosum leprosum (ENL) classically presents with tender, coppery, evanescent nodules along with constitutional features and visceral involvement. However, uncommon morphological variants of ENL-like erythema nodosum necroticans, erythema multiforme (EM)-like ENL, Sweet's syndrome (SS)-like ENL, Lucio phenomenon, and reactive perforating type of ENL have also been described in the literature. The primary objective of this study was to describe the clinical features of the severe and uncommon morphological variants of ENL.

Methods: This was an observational case series with retrospective review of records of all ENL patients with ulceronecrotic lesions admitted in the Department of Dermato-venereo-leprology of a tertiary health center of central India over a period of 2 years.

Results: Eighteen patients were included, all of whom had ulceronecrotic lesions. Four out of them had EM like ENL, two had SS-like presentation, and one of them had annular bullous lesions over old infiltrated plaques of leprosy.

Conclusions: Uncommon variants of ENL can be very commonly misdiagnosed in patients, especially in those who have not been previously diagnosed with leprosy. Hence, a high index of suspicion is required in such cases to avoid delay in the diagnosis and resulting morbidity.