A prospective observational cohort study and systematic review of 40 patients with mouth and genital ulcers with inflamed cartilage (MAGIC) syndrome.

OBJECTIVE: Mouth and genital ulcers with inflamed cartilage (MAGIC) syndrome is characterized by overlapping features of relapsing polychondritis (RP) and Behcet's disease (BD). To date, no studies have defined the clinical spectrum of disease in a cohort of patients with MAGIC syndrome. METHODS: Adult patients within an ongoing prospective, observational cohort study in RP were clinically assessed for MAGIC syndrome. A systematic review was conducted to identify additional cases of MAGIC syndrome by searching four databases: PubMed (US National Library of Medicine), Embase (Elsevier), Scopus (Elsevier) and Web of Science: Core Collection (Clarivate Analytics). The inclusion criteria used were: [1] patients of any age or gender who were diagnosed with MAGIC syndrome, or both RP and BD; [2] case report or case series study; [3] published from 1985 - July 2020; and [4] in English language. Risk of bias was assessed using a checklist developed by the authors and based on the Consensus-based Clinical Case Reporting (CARE) Guidelines. Search results screening, article inclusion, data extraction and risk of bais assessment was performed independently by two investigators. Clinical characteristics, particularly BD-related features, were compared between patients with MAGIC syndrome and cases of non-MAGIC RP. The performance characteristics of different criteria to classify MAGIC syndrome were also evaluated. RESULTS: Out of 96 patients with RP, 13 (14%) patients were diagnosed with MAGIC syndrome. For the systematic review, 380 articles were retrieved of which 90 were screened at title and abstract levels. Of these screened, 60 were excluded and 30 proceeded to full text review where an additional 8 were excluded. Twenty-two articles were included in our review and from which 27 additional cases of MAGIC syndrome were identified. Pooling all 40 cases together and comparing them with non-MAGIC RP, there was a significantly higher prevalence of ocular involvement (28% vs 4%, p<0.01), cutaneous involvement (35% vs 1%, p<0.01), GI involvement (23% vs 4%, p<0.01), and CNS involvement (8% vs 0, p = 0.04) in MAGIC syndrome. A higher prevalence of aortitis (23% vs 1%, p<0.01), Raynaud's phenomenon (54% vs 11%, p<0.01), and elevated anti-collagen II antibodies (50% vs 9%, p = 0.04) were observed in MAGIC syndrome. Fulfillment of either McAdam's or Damiani's Criteria for RP plus the International Criteria for Behçet's Disease had excellent sensitivity (98%) to classify cases of MAGIC syndrome. CONCLUSION: A substantial proportion of patients with RP can be clinically diagnosed with MAGIC syndrome. These patients have features of RP, BD, and other unique features including aortitis, Raynaud's phenomenon and elevated anti-collagen II antibodies.

Somatic Mutations in UBA1 Define a Distinct Subset of Relapsing Polychondritis Patients With VEXAS.

OBJECTIVE: Somatic mutations in UBA1 cause a newly defined syndrome known as VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic syndrome). More than 50% of patients currently identified as having VEXAS met diagnostic criteria for relapsing polychondritis (RP), but clinical features that characterize VEXAS within a cohort of patients with RP have not been defined. We undertook this study to define the prevalence of somatic mutations in UBA1 in patients with RP and to create an algorithm to identify patients with genetically confirmed VEXAS among those with RP. METHODS: Exome and targeted sequencing of UBA1 was performed in a prospective observational cohort of patients with RP. Clinical and immunologic characteristics of patients with RP were compared based on the presence or absence of UBA1 mutations. The random forest method was used to derive a clinical algorithm to identify patients with UBA1 mutations. RESULTS: Seven of 92 patients with RP (7.6%) had UBA1 mutations (referred to here as VEXAS-RP). Patients with VEXAS-RP were all male, were on average ≥45 years of age at disease onset, and commonly had fever, ear chondritis, skin involvement, deep vein thrombosis, and pulmonary infiltrates. No patient with VEXAS-RP had chondritis of the airways or costochondritis. Mortality was greater in VEXAS-RP than in RP (23% versus 4%; P = 0.029). Elevated acute-phase reactants and hematologic abnormalities (e.g., macrocytic anemia, thrombocytopenia, lymphopenia, multiple myeloma, myelodysplastic syndrome) were prevalent in VEXAS-RP. A decision tree algorithm based on male sex, a mean corpuscular volume >100 fl, and a platelet count <200 ×103 /µl differentiated VEXAS-RP from RP with 100% sensitivity and 96% specificity. CONCLUSION: Mutations in UBA1 were causal for disease in a subset of patients with RP. This subset of patients was defined by disease onset in the fifth decade of life or later, male sex, ear/nose chondritis, and hematologic abnormalities. Early identification is important in VEXAS given the associated high mortality rate.

Somatic Mutations in UBA1 and Severe Adult-Onset Autoinflammatory Disease.

BACKGROUND: Adult-onset inflammatory syndromes often manifest with overlapping clinical features. Variants in ubiquitin-related genes, previously implicated in autoinflammatory disease, may define new disorders. METHODS: We analyzed peripheral-blood exome sequence data independent of clinical phenotype and inheritance pattern to identify deleterious mutations in ubiquitin-related genes. Sanger sequencing, immunoblotting, immunohistochemical testing, flow cytometry, and transcriptome and cytokine profiling were performed. CRISPR-Cas9-edited zebrafish were used as an in vivo model to assess gene function. RESULTS: We identified 25 men with somatic mutations affecting methionine-41 (p.Met41) in UBA1, the major E1 enzyme that initiates ubiquitylation. (The gene UBA1 lies on the X chromosome.) In such patients, an often fatal, treatment-refractory inflammatory syndrome develops in late adulthood, with fevers, cytopenias, characteristic vacuoles in myeloid and erythroid precursor cells, dysplastic bone marrow, neutrophilic cutaneous and pulmonary inflammation, chondritis, and vasculitis. Most of these 25 patients met clinical criteria for an inflammatory syndrome (relapsing polychondritis, Sweet's syndrome, polyarteritis nodosa, or giant-cell arteritis) or a hematologic condition (myelodysplastic syndrome or multiple myeloma) or both. Mutations were found in more than half the hematopoietic stem cells, including peripheral-blood myeloid cells but not lymphocytes or fibroblasts. Mutations affecting p.Met41 resulted in loss of the canonical cytoplasmic isoform of UBA1 and in expression of a novel, catalytically impaired isoform initiated at p.Met67. Mutant peripheral-blood cells showed decreased ubiquitylation and activated innate immune pathways. Knockout of the cytoplasmic UBA1 isoform homologue in zebrafish caused systemic inflammation. CONCLUSIONS: Using a genotype-driven approach, we identified a disorder that connects seemingly unrelated adult-onset inflammatory syndromes. We named this disorder the VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome. (Funded by the NIH Intramural Research Programs and the EU Horizon 2020 Research and Innovation Program.).