Abstract
NK/T-Cell lymphomas (NKTL) typically present as erythematous or violaceous plaques or tumors. We describe an unusual case of NKTL manifesting as folliculitis unresponsive to usual therapies. A 60-year-old man with Parkinson’s disease was referred for a second opinion of pruritic erythematous and edematous papules and pustules on the trunk and arms for 1 year. The working diagnosis was eosinophilic pustular folliculitis, based on a biopsy showing folliculitis and prominent eosinophils. He had failed multiple therapies including antibiotics, antifungals, ivermectin, permethrin, phototherapy, methotrexate, and most recently prednisone and isotretinoin. We performed another biopsy which showed acute folliculitis with Demodex mites and rare eosinophils. We did not pursue further Demodex-directed treatment and opted instead for a course of cephalexin, staphylococcal decolonization, and discontinuation of prednisone and isotretinoin. Two months later, he returned with worsening rash and pruritus and reported a 15-pound unintentional weight loss. Examination demonstrated more prominent edematous papules. Repeat biopsy showed a dense dermal mononuclear cell infiltrate with accentuation around dilated follicular structures and some early vascular destruction. The cells of interest were positive for CD56, TIA-1, and granzyme-B. EBER ISH (EBV) was positive in the majority of the cells. Whole blood EBV PCR was 215,000 copies/mL. Laryngoscopy and positron emission tomography scans were negative. A diagnosis of EBV+ NK/T-cell lymphoproliferative disorder was made. The patient subsequently pursued treatment at an outside facility. This case highlights the variable clinical presentation of NKTL, including folliculitis. Multiple biopsies may be necessary to reach an accurate diagnosis.