A Rare Case of Erythema Nodosum Leprosum Presenting Clinically as Type 1 Reaction

Leprosy reactions represent acute immunologically mediated inflammatory episodes, which may interrupt the otherwise chronic course of Leprosy. They are of two major types - Type 1 Lepra reaction, or Reversal reaction, and Type 2 Lepra reaction or ENL. Reactional states in leprosy are the most common cause of permanent nerve damage, deformity, and disability. However, atypical presentations of reactions may pose a diagnostic challenge for the treating dermatologist. Here we report an unusual case of Lepra reaction clinically presenting as Type 1 reaction, and having histological features of ENL. The patient presented with erythematous, edematous and infiltrated plaques as the predominant lesions, with a history of recurrent episodes of such lesions, associated with constitutional symptoms. The clinical picture was in favor of BT downgrading to BL leprosy in Type 1 reaction. On the basis of the histopathological findings, a diagnosis of ENL was suggested. However, absence of typical ENL lesions, and clinical resemblance of the lesions to Type 1 reaction makes this case unusual and hence it is being reported.