Neutrophilic dermatoses

Area of Science:

• Dermatology
• Immunology
• Internal Medicine

Background:

• Neutrophilic dermatoses (ND) are inflammatory skin conditions defined by neutrophil infiltration without infection.
• Classification is based on neutrophil location and clinical presentation.
• ND pathogenesis involves innate immune system activation or myeloid cell clonal expansion.

Approach:

• Review of pathophysiology and classification of major ND types.
• Detailed examination of clinical and histopathological features.
• Highlighting diagnostic investigations for associated diseases and differential diagnoses.

Key Points:

• ND classification relies on neutrophil localization and clinical signs.
• Pathways include hereditary immune activation and somatic myeloid cell activation (e.g., VEXAS syndrome).
• Many ND patients have underlying conditions like hematologic malignancies or inflammatory diseases.

Conclusions:

• ND diagnosis requires excluding infections and considering underlying systemic diseases.
• Histopathology and clinical features guide classification and diagnosis.
• Appropriate investigations are crucial for identifying associated conditions and ruling out differentials.