Eosinophilic pustular folliculitis (EPF) was originally described in 1965 and has since evolved into 3 distinct subtypes: classic, immunosuppressed (IS), and infantile types. Immunosuppressed EPF can be further subdivided into human immunodeficiency virus (HIV) associated (IS-HIV) and non-HIV associated. Human immunodeficiency virus–seronegative cases have been associated with underlying malignancies (IS-heme) or chronic immunosuppression, such as that seen in transplant patients.
Case Report
A 52-year-old man with a medical history limited to prostate adenocarcinoma treated with a robotic prostatectomy presented with a pruritic red rash on the face, neck, shoulders, and chest of 1 month’s duration. The patient previously completed a course of azithromycin 250 mg, intramuscular triamcinolone, and oral prednisone with only minor improvement. Physical examination demonstrated multiple pink folliculocentric papules and pustules scattered on the head (Figure 1A), neck, and chest (Figure 1B), as well as edematous pink papules and plaques on the forehead (Figures 1C and 1D). The palms, soles, and oral mucosa were clear.
Figure 1. Multiple pink folliculocentric papules and pustules on the head (A), neck, and chest (B), as well as edematous pink papules and plaques on the forehead (C and D).
Initial biopsy of the right side of the chest was nonspecific and most consistent with a reaction to an arthropod bite. The patient was started on oral doxycycline 100 mg twice daily for 2 weeks. With no improvement seen, additional biopsies were obtained from the left side of the chest and forehead. The biopsy of the chest showed ruptured folliculitis with evidence of acute and chronic inflammation. The biopsy of the forehead demonstrated eosinophilic follicular spongiosis with intrafollicular Langerhans cell microgranulomas along with abundant eosinophils adjacent to follicles, consistent with EPF (Figure 2). Serum HIV testing was negative. Serum white blood cell count was normal at 6400/µL (reference range, 4500–11,000/µL) with mild elevation of eosinophils (8%). The remaining complete blood cell count and comprehensive metabolic panel were within reference range. The patient was subsequently started on oral indomethacin 25 mg twice daily and triamcinolone cream 0.1%. Within a few days he experienced initial improvement in his symptoms of pruritus and diminution in the number of inflammatory follicular papules.
Figure 2. Follicular spongiosis and abundant perifollicular eosinophils admixed with lymphohistiocytes and neutrophils (A and B)(H&E, original magnifications ×10 and ×20).
Approximately 1 month after presentation, he began to experience symptoms of dysphagia and fatigue. In addition, tonsillar hypertrophy and palpable neck and axillary lymphadenopathy were present. Computed tomography of the neck, chest, and abdomen showed diffuse lymphadenopathy. Full-body positron emission tomography–computed tomography demonstrated extensive metabolically active lymphoma in multiple nodal groups above and below the diaphragm. There also was lymphomatous involvement of the spleen. An axillary lymph node biopsy was diagnostic for mantle cell lymphoma (CD4:CD8, 1:1; CD45 negative; CD20 positive; CD5 positive). He was subsequently initiated on a rituximab chemotherapeutic regimen via intravenous infusion and completed a total of 8 cycles. Although chemotherapy treatment improved the EPF, oral indomethacin and topical triamcinolone were useful in clearing disease.