Folliculotropic mycosis fungoides with leukaemic involvement in middle childhood: a rare encounter.

Mycosis fungoides (MF) is the most common type of cutaneous T-cell lymphoma in adults. However, it is rare in middle childhood. Such cases usually present with hypopigmented patches that may mimic common childhood dermatoses, thereby causing a delay in the diagnosis. Sezary syndrome is a rare and aggressive leukaemic variant of cutaneous lymphoma. We report a patient in middle childhood who presented with recurring non-specific folliculotropic manifestations. The final diagnosis of MF was arrived at after excluding all other possible dermatoses. Within a few months of skin manifestations, our index child was found to have blood involvement with similar clonal T-lymphoid cells. Such rapid development of Sezary syndrome within months of cutaneous presentation has never been described. There are no established treatment guidelines for the same in paediatric population. The patient underwent a matched sibling allogeneic transplant after a course of topical steroids and skin electron beam therapy.