Sweet syndrome associated with moderate leukocyte adhesion deficiency type I: a case report and review of the literature.

Sweet syndrome is an acute febrile neutrophilic dermatosis characterized by the infiltration of neutrophils into the skin. It may occur idiopathically or be linked to malignancies, inflammatory or autoimmune diseases. Leukocyte adhesion deficiency type I (LAD-I) is an inborn error immunity wherein leukocytes lack adhesion molecules necessary for migration to infection sites due to mutations in the CD18 gene encoding ß2 integrins. We present a case of a 16-month-old female initially diagnosed and treated for Sweet syndrome based on histopathological findings with recurrent flare episodes. Subsequent workup revealed LAD-I, making this case the first documented association between Sweet syndrome and LAD-I. Moreover, we reviewed the pertinent literatures detailing the concurrence of neutrophilic dermatosis and immunodeficiency disorders. This case underscores the significance of comprehensive evaluation for Sweet syndrome patients who are refractory to conventional treatments.

Clinical and histological features of histiocytoid Sweet syndrome associated with VEXAS syndrome.

BACKGROUND: VEXAS (Vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome is caused by acquired somatic mutations in UBA1. Sweet-syndrome-like skin disorders [and especially histiocytoid Sweet syndrome (HSS)] may be associated with VEXAS syndrome. OBJECTIVES: To characterize the clinical and histopathological features of HSS in patients with VEXAS syndrome. METHODS: Skin biopsies with a histological diagnosis of HSS at Rennes University Medical Center (Rennes, France) between October 2011 and January 2022 were reviewed in this study. Sanger sequencing and digital polymerase chain reaction were used to screen skin, blood and bone marrow samples for UBA1 variants, and thus classify patients as having VEXAS syndrome or not. We evaluated the clinical, histological and molecular (UBA1) characteristics of patients with or without VEXAS syndrome. RESULTS: We compared 15 skin biopsies from 7 patients found to have VEXAS syndrome and 19 skin biopsies from 15 patients without VEXAS syndrome. Persistent C-reactive protein elevation, macrocytosis, anaemia and haematological malignancies were more prevalent in patients with VEXAS syndrome [6/7 (86%), 6/7 (86%), 7/7 (100%) and 6/7 (86%), respectively] than in patients without [5/14 (36%), 6/15 (40%), 8/15 (53%) and 8/15 (53%), respectively]. These features sometimes appeared after the first skin manifestations, and a UBA1 mutation was found in the skin of five patients with VEXAS syndrome. Dermal infiltration by reniform histiocytoid cells (myeloperoxidase-positive and/or CD163-positive) and a periadnexal distribution were more frequently observed in VEXAS syndrome biopsies [15/15 (100%) and 3/15 (20%), respectively, vs. 11/19 (58%) and 0/19 (0%) in non-VEXAS syndrome biopsies, respectively]. CONCLUSIONS: Our findings might help pathologists to consider a diagnosis of VEXAS syndrome and to initiate early genetic testing.

Neutrophilic dermatosis in a patient with an IKZF1 variant and a review of monogenic autoinflammatory disorders presenting with neutrophilic dermatoses.

Monogenic diseases of immune dysregulation should be considered in the evaluation of children presenting with recurrent neutrophilic dermatoses in association with systemic signs of inflammation, autoimmune disease, hematologic abnormalities, and opportunistic or recurrent infections. We report the case of a 2-year-old boy presenting with a neutrophilic dermatosis, found to have a novel likely pathogenic germline variant of the IKAROS Family Zinc Finger 1 (IKZF1) gene; the mutation likely results in a loss of function dimerization defective protein based on reports and studies of similar variants. IKZF1 variants could potentially lead to aberrant neutrophil chemotaxis and development of neutrophilic dermatoses. Long-term surveillance is required to monitor the development of hematologic malignancy, autoimmunity, immunodeficiency, and infection in patients with pathogenic IKZF1 germline variants.

Clinical characteristics, disease trajectories and management of vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic (VEXAS) syndrome: a systematic review.

BACKGROUND: VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome is a newly discovered autoinflammatory condition characterised by somatic mutation of the UBA1 gene. The syndrome leads to multi-system inflammation affecting predominantly the skin, lungs and bone marrow. METHODS: We undertook a systematic review of the multisystem features and genotypes observed in VEXAS syndrome. Articles discussing VEXAS syndrome were included. Medline, Embase and Cochrane databases were searched. Information was extracted on: demographics, type and prevalence of clinical manifestations, genetic mutations and treatment. Meta-analysis using a random effects model was used to determine pooled estimates of serum markers. RESULTS: From 303 articles, 90 were included, comprising 394 patients with VEXAS. 99.2% were male, with a mean age of 67.1 years (SD 8.5) at disease onset. The most frequent diagnoses made prior to VEXAS were: relapsing polychondritis (n = 59); Sweet's syndrome (n = 24); polyarteritis nodosa (n = 11); and myelodysplastic syndrome (n = 10). Fever was reported in 270 cases (68.5%) and weight loss in 79 (20.1%). Most patients had haematological (n = 342; 86.8%), dermatological (n = 321; 81.5%), pulmonary (n = 297; 75.4%%) and musculoskeletal (n = 172; 43.7%) involvement, although other organ manifestations of varying prevalence were also recorded. The most commonly reported mutations were "c.122T > C pMET41Thr" (n = 124), "c.121A > G pMET41Val" (n = 62) and "c.121A > C pMet41Leu" (n = 52). Most patients received glucocorticoids (n = 240; 60.9%) followed by methotrexate (n = 82; 20.8%) and IL-6 inhibitors (n = 61, 15.4%). One patient underwent splenectomy; 24 received bone marrow transplants. CONCLUSION: VEXAS syndrome is a rare disorder affecting predominantly middle-aged men. This is the first systematic review to capture clinical manifestations, genetics and treatment of reported cases. Further studies are needed to optimise treatment and subsequently reduce morbidity and mortality.