Unveiling VEXAS Syndrome: When Skin Manifestations and Monoclonal Gammopathy Precede Myeloid-Lineage Hematologic Abnormality.

VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome is a rare disorder caused by somatic UBA1 gene mutations, characterized by autoinflammation and hematologic abnormalities, particularly affecting myeloid-lineage progenitors. Sensitive markers include macrocytic anemia, vacuolization of bone marrow precursors, and myelodysplasia. Here, we report the first case of VEXAS syndrome presenting with neutrophilic dermatosis and a serum monoclonal component, without myeloid-lineage hematologic abnormalities atonset. This case underscores the importance of including VEXAS syndrome in the differential diagnosis when monoclonal gammopathy is associated with rheuamtologic features, particularly in older patients presenting with unexplained cutaneous inflammatory manifestations and a serum clonal component, as such presentations may precede the development of classical hematologic abnormalities.