Background:
Herein, we present the second documented case of a rare pediatric lower extremity unilateral unilocular cutaneous BPDCN in a relatively asymptomatic Hispanic child who had unusual initial transient improvement from antibiotic treatment.
Case presentation:
A well-nourished 12-year-old Hispanic male with no significant past medical history developed a sizable progressively enlarging lesion on his right inner calf of approximately two months duration after a ground level fall. Review of systems noted night sweats. All imaging findings were unremarkable except for subcutaneous soft tissue ill-defined infiltrative swelling. Routine laboratory findings were non-contributory. The differential of chronic atypical infectious etiology was initially favored. Interestingly, it did have transient improvement with drainage and antibiotic treatment (Cephalexin/Keflex, 500mg). Approximately two months later, the lesional appearance worsened and patient was eventually diagnosed with blastic plasmacytoid dendritic cell neoplasm.
Conclusion:
Pediatric blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive neoplastic process involving precursor plasmacytoid dendritic cells. Diagnostic evaluation of this intricate heterogeneous entity necessitates the incorporation of various clinical and laboratory findings. Given the challenging nature of this entity, it is imperative to arrive at timely diagnosis with tissue biopsy and initiate appropriate prompt management.