VEXAS without vacuoles: Linking genotype to phenotype

Introduction VEXAS syndrome is a rare condition characterized by somatic mutations in the ubiquitin‐like modifier activating enzyme 1 ( UBA1 ) gene and a constellation of clinical/morphologic findings, including the presence of cytoplasmic vacuoles within bone marrow hematopoietic cells. Methods and objectives In this report, we present a case of a male patient diagnosed with VEXAS‐associated myelodysplastic syndrome following the detection of a non‐canonical UBA1 p.Gly477Ala variant whose bone marrow biopsy revealed a conspicuous absence of cytoplasmic vacuolization in hematopoietic cells. This case prompts a comprehensive review of the existing literature on the significance and pathobiology of vacuolization in the context of VEXAS and UBA1 mutations.