Necrobiotic xanthogranulomatosis

Background

• Form of non-Langerhans cell histiocytosis
• Associated with paraproteinemia from plasma cell dyscrasia or lymphoproliferative disorder

Clinical Manifestations

• Cutaneous involvement
  • Yellow-to-orange papules, plaques or nodules
  • Usually periorbital, but can appear elsewhere on the face, as well as extremities and trunk being common
  • Can ulcerate
  • Can be red or pink, brown, or purple
• Can involve eye (most common extracutaneous manifestation), heart, GI tract, liver, and lung

Diagnostic Criteria

• Proposed in 2020
• Criteria are divided into major and minor
  • Major criteria:
    • Cutaneous papules, plaques, and/or nodules, most often yellow or orange in color.
    • Histopathological features demonstrating palisading granulomas with lymphoplasmacytic infiltrate and zones of necrobiosis. Characteristic features that are variably present include cholesterol clefts and/or giant cells (Touton or foreign body).
  • Minor criteria:
    • Paraproteinemia, most often IgG-κ, plasma-cell dyscrasia, and/or other associated lymphoproliferative disorder.
    • Periorbital distribution of cutaneous lesions.
• Must have both major criteria plus 1 minor criterion

Management

• No guidelines or well-established protocols
• IVIg, antimalarials, intralesional triamcinolone, chemotherapy, lenalidomide or thalidomide have all been found to be helpful in case series

Further Reading

• A Multicenter Cross-Sectional Study and Systematic Review of Necrobiotic Xanthogranuloma With Proposed Diagnostic Criteria. JAMA Dermatol. 2020;156(3):270-279. doi: 10.1001/jamadermatol.2019.4221