Faculty Bibliography

Myeloid and erythroid precursor vacuolation is a common dysplastic finding associated with myeloid malignancies, toxins, drug, and nutritional deficiencies. It has been described as a core morphologic feature in VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome. We sought to determine the number of cases attributable to VEXAS syndrome in bone marrow biopsies and aspirates (BAMB) reporting myeloid precursor vacuolation. We reviewed 1318 individual BAMB reports from January 2020 to July 2021 where "vacuole(s)," "vacuolation," or "vacuolated" was reported. Bone marrow biopsies with vacuolation confined to blasts or those completed as routine workup prior to stem cell transplant or post induction chemotherapy for AML (acute myeloid leukemia) were excluded. Myeloid and erythroid precursor vacuolation was noted in 219 reports representing 210 patients. The most common etiology was myelodysplastic syndrome (MDS) (38.6%), AML (16.7%), lymphoproliferative disorders and multiple myeloma (7.6%), drug or toxin exposure (5.2%) myeloproliferative neoplasm (MPN) or MPN/MDS overlap syndrome (4.3%). VEXAS syndrome was determined to be the etiology in 2.9% of patients. Two additional cases of VEXAS syndrome with bone marrow biopsies reported in the specified time frame did not explicitly report myeloid or erythroid precursor vacuolation but were identified based on clinical suspicion and repeat BAMB review. Myeloid and erythroid precursor vacuolation is a dysplastic feature attributable to VEXAS syndrome in at least 2.9% of cases. Standardized reporting of vacuolization, triaging of molecular sequencing and optimal treatment of this disorder are critical issues facing those seeing patients with suspected VEXAS syndrome.

IMPORTANCE:VEXAS (vacuoles, E1-ubiquitin-activating enzyme, X-linked, autoinflammatory, somatic) syndrome is a disease with rheumatologic and hematologic features caused by somatic variants in UBA1. Pathogenic variants are associated with a broad spectrum of clinical manifestations. Knowledge of prevalence, penetrance, and clinical characteristics of this disease have been limited by ascertainment biases based on known phenotypes. OBJECTIVE:To determine the prevalence of pathogenic variants in UBA1 and associated clinical manifestations in an unselected population using a genomic ascertainment approach. DESIGN, SETTING, AND PARTICIPANTS:This retrospective observational study evaluated UBA1 variants in exome data from 163 096 participants within the Geisinger MyCode Community Health Initiative. Clinical phenotypes were determined from Geisinger electronic health record data from January 1, 1996, to January 1, 2022. EXPOSURES:Exome sequencing was performed. MAIN OUTCOMES AND MEASURES:Outcome measures included prevalence of somatic UBA1 variation; presence of rheumatologic, hematologic, pulmonary, dermatologic, and other findings in individuals with somatic UBA1 variation on review of the electronic health record; review of laboratory data; bone marrow biopsy pathology analysis; and in vitro enzymatic assays. RESULTS:In 163 096 participants (mean age, 52.8 years; 94% White; 61% women), 11 individuals harbored likely somatic variants at known pathogenic UBA1 positions, with 11 of 11 (100%) having clinical manifestations consistent with VEXAS syndrome (9 male, 2 female). A total of 5 of 11 individuals (45%) did not meet criteria for rheumatologic and/or hematologic diagnoses previously associated with VEXAS syndrome; however, all individuals had anemia (hemoglobin: mean, 7.8 g/dL; median, 7.5 g/dL), which was mostly macrocytic (10/11 [91%]) with concomitant thrombocytopenia (10/11 [91%]). Among the 11 patients identified, there was a pathogenic variant in 1 male participant prior to onset of VEXAS-related signs or symptoms and 2 female participants had disease with heterozygous variants. A previously unreported UBA1 variant (c.1861A>T; p.Ser621Cys) was found in a symptomatic patient, with in vitro data supporting a catalytic defect and pathogenicity. Together, disease-causing UBA1 variants were found in 1 in 13 591 unrelated individuals (95% CI, 1:7775-1:23 758), 1 in 4269 men older than 50 years (95% CI, 1:2319-1:7859), and 1 in 26 238 women older than 50 years (95% CI, 1:7196-1:147 669). CONCLUSIONS AND RELEVANCE:This study provides an estimate of the prevalence and a description of the clinical manifestations of UBA1 variants associated with VEXAS syndrome within a single regional health system in the US. Additional studies are needed in unselected and genetically diverse populations to better define general population prevalence and phenotypic spectrum.

OBJECTIVE/UNASSIGNED:, the gene encoding the anti-inflammatory IL-1 receptor antagonist (IL-1Ra), on the cytokine release syndrome and mortality. METHODS/UNASSIGNED:gene were assessed for association with laboratory markers of the cytokine release syndrome (CRS) and mortality. RESULTS/UNASSIGNED:rs419598 CC SNV exhibited lower inflammatory biomarker levels, and was associated with reduced mortality compared to the CT/TT genotype in men (OR 0.49 (0.23 - 1.00); 0.052), with the most pronounced effect observed between the ages of 55-74 [5.5% vs. 18.4%, p<0.001]. CONCLUSION/UNASSIGNED:modulates the COVID-19 cytokine release syndrome via endogenous " anti-inflammatory" mechanisms. SIGNIFICANCE STATEMENT/UNASSIGNED:merits further evaluation in severe SARS-CoV-2 infection.

OBJECTIVES/OBJECTIVE:, is an autoinflammatory disease. METHODS:mutations on protein function and immune signalling. RESULTS:T237M mutation exhibited subclinical inflammation.Clinical features not conventionally attributed to inflammation were also common in the cohort and included short dental roots, enamel defects and decreased salivary flow. CONCLUSION/CONCLUSIONS:and some features of disease are amenable to immunomodulatory therapy.

Somatic mutations in UBA1 cause VEXAS (Vacuoles, E1 ubiquitin activating enzyme, X-linked, Autoinflammatory Somatic) syndrome, an adult-onset inflammatory disease with an overlap of hematologic manifestations. VEXAS syndrome is characterized by a high mortality rate and significant clinical heterogeneity. We sought to determine independent predictors of survival in VEXAS and to understand the mechanistic basis for these factors. We analyzed 83 patients with somatic pathogenic variants in UBA1 at p.Met41 (p.Met41Leu/Thr/Val), the start codon for translation of the cytoplasmic isoform of UBA1 (UBA1b). Patients with the p.Met41Val genotype were most likely to have an undifferentiated inflammatory syndrome. Multivariate analysis showed ear chondritis was associated with increased survival, while transfusion dependence and the p.Met41Val variant were independently associated with decreased survival. Using in vitro models and patient-derived cells, we demonstrate that p.Met41Val variant supports less UBA1b translation than either p.Met41Leu or p.Met41Thr, providing a molecular rationale for decreased survival. In addition, we show that these three canonical VEXAS variants produce more UBA1b than any of the six other possible single nucleotide variants within this codon. Finally, we report a patient, clinically diagnosed with VEXAS syndrome, with two novel mutations in UBA1 occurring in cis on the same allele. One mutation (c.121 A>T; p.Met41Leu) caused severely reduced translation of UBA1b in a reporter assay, but co-expression with the second mutation (c.119 G>C; p.Gly40Ala) rescued UBA1b levels to those of canonical mutations. We conclude that regulation of residual UBA1b translation is fundamental to the pathogenesis of VEXAS syndrome and contributes to disease prognosis.

Ubiquitylation is an essential post-translational modification that regulates intracellular signalling networks by triggering proteasomal substrate degradation, changing the activity of substrates or mediating changes in proteins that interact with substrates. Hundreds of enzymes participate in reversible ubiquitylation of proteins, some acting globally and others targeting specific proteins. Ubiquitylation is essential for innate immune responses, as it facilitates rapid regulation of inflammatory pathways, thereby ensuring sufficient but not excessive responses. A growing number of inborn errors of immunity are attributed to dysregulated ubiquitylation. These genetic disorders exhibit broad clinical manifestations, ranging from susceptibility to infection to autoinflammatory and/or autoimmune features, lymphoproliferation and propensity to malignancy. Many autoinflammatory disorders result from disruption of components of the ubiquitylation machinery and lead to overactivation of innate immune cells. An understanding of the disorders of ubiquitylation in autoinflammatory diseases could enable the development of novel management strategies.

VEXAS (Vacuoles, E1 enzyme, X-linked, Autoinflammatory, Somatic) syndrome is a newly described disease due to somatic mutations in UBA1, encoding ubiquitin-activating enzyme 1. Patients with VEXAS syndrome have hematologic features, such as macrocytic anemia and myelodysplastic syndrome, and systemic inflammation, including cutaneous involvement. Our aim was to characterize the spectrum of skin manifestations in a large cohort of patients with VEXAS. 87 males and 1 female with genetically confirmed VEXAS syndrome were included in this retrospective study. Mean age at disease onset was 64 years (range 39-78). Most patients (n=71, 81%) had skin involvement. Initial disease presentation was confined to skin in 16 patients (18.2%) or to skin with systemic features in 19 (21%) patients. Skin lesions were painful/tender (n=15, 21.1%) or pruritic (n=13, 18.3%), characterized by erythema (n=20, 28.2%) or nodules (n=17, 23.9%), and occurred most frequently in an acral distribution (n=25, 35.2%). 110 skin biopsies were performed in 45 patients. Skin biopsies were interpreted as small or medium vessel vasculitis (n=29, 26.4%), Sweet syndrome (n=24, 21.8%), connective tissue disease (n=9, 8.2%), or erythema nodosum (n=7, 6.4%). Histologic review of 11 cases identified a neutrophilic predominance (n=6, 54.5%) in the epidermis (n=2, 18.2%), papillary dermis (n=6, 54.5%) and reticular dermis (n=5, 45.5%). Skin lesions improved with glucocorticoids in 85.5% of patients (n=47/55), but relapse after tapering was common (60%, n=33/55). Severe injection site reactions to anakinra were frequent (64.3%, n=9/14). Skin lesions are a common, early feature of VEXAS syndrome and share similarities in clinical and histologic presentation with other inflammatory skin disease. Appreciation of the spectrum of skin findings in VEXAS will facilitate early diagnosis.
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Vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic (VEXAS) syndrome was recently identified by genotype-driven approach. This syndrome is characterised by the presence of somatic mutations affecting methionine-41 (p.Met41) in UBA1 gene. All the identified patients were adult males who had recurrent fevers, cytopenias, dysplastic bone marrow with vacuoles in myeloid and erythroid precursors, neutrophilic skin and lung tissue inflammation and often had treatment refractory and fatal disease course. The various phenotypes reported with VEXAS syndrome include relapsing polychondritis, giant cell arteritis, polyarteritis nodosa, Sweet's syndrome, myelodysplastic syndrome and multiple myeloma.