Authors' reply

Hiral Shah¹ , Anup Kumar Tiwary² , Piyush Kumar³

¹ Department of Dermatology, Baroda Medical College, Vadodara, Gujarat, India
² Department of Dermatology, Government Medical College and Hospital, Haldwani, Uttarakhand, India
³ Department of Dermatology, Katihar Medical College, Katihar, Bihar, India

Correspondence Address:
Piyush Kumar
Department of Dermatology, Katihar Medical College, Katihar, Bihar
India

Sir,

We thank the author for taking interest in our article and raising the issue of potential role of transepidermal elimination of live lepra bacilli in transmission of the disease. We completely agree with the views and concern of the correspondent in connection with the significance of transepidermal elimination in cutaneous spread of leprosy in histoid and lepromatous cases. One of the authors (PK) has recently observed a lepromatous leprosy case with molluscoid (or umbilicated) papules and transepidermal elimination of lepra bacilli (unpublished observation). The publications on transepidermal elimination of lepra bacilli are scarce.^[1],[2],[3] However, considering the load of lepromatous cases in an endemic country like India, the authors believe it to be an underobserved and underreported phenomenon. The significance of transepidermal elimination of lepra bacilli is not clear, but the authors have speculated that it might play a role in cutaneous transmission of leprosy. The implications of “probable cutaneous transmission” are profound; household contacts, leprosy researchers, and leprosy control program need to be notified.

Although the role of basal keratinocytes, Langerhans cells and T cells has been suggested in transmission of lepra bacilli from the upper dermis to different epidermal layers, precise mechanism of this phenomenon in leprosy is not yet clear.^[2],[4] Therefore, we have kept the example of histoid leprosy under “other and unspecified conditions” in [Table 1]. We do concur that further studies with substantial evidence are much needed to unravel this event considering the global burden of leprosy and challenges in its elimination.^[1],[2]

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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