Maronese, Carlo A

Abstract Background Small vessel vasculitides (SVV) comprise a heterogeneous group of cutaneous SVV (CSVV) that can be skin‐limited or systemic. Given their diverse forms and symptoms and the lack of a standardized diagnostic approach, it is crucial to establish clear and consensus‐driven recommendations for diagnosis. Objectives To standardize diagnosis for the detection of the type, extent, potential causes or underlying conditions of CSVV. Methods International experts comprised the panel. The Delphi panel data was collected through two rounds of questionnaires. Agreement was measured using an 11‐point Likert scale (0 = strongly disagree, 10 = strongly agree). A 7‐vote minimum was required for agreement on each statement. Delphi panel statements scoring 3–7 were discussed during the meeting. Results 20 experts participated in the first round of the Delphi panel, while 17 experts took part in the second. They agreed that the diagnosis of CSVV relies on a combination of clinical manifestations, laboratory findings and histopathology. Palpable purpura on the lower extremities is recognized as the most reliable hallmark for most SVV and a sign of immune complex vasculitis. When the latter is suspected, a skin biopsy for direct immunofluorescence (DIF) should be obtained from an early, partially blanchable macule because the type of perivascular immunoglobulin is important for further diagnosis. The proper selection of biopsy sites for routine HE biopsy depends on the morphology of lesions. A comprehensive medical history and selected laboratory testing should be conducted to investigate organ involvement, potential causes and associated conditions. The extent of diagnostic procedures should be based on the severity, duration, systemic symptoms and recurrence of SVV. Conclusions Experts reached a strong consensus on the management of CSVV patients, culminating in the first International Consensus Statement for adult CSVV. This statement proposes a practical management algorithm and underscores the importance of collaboration in rare diseases management.

AbstractYao syndrome (YAOS) is a novel systemic autoinflammatory disease linked to the nucleotide‐binding oligomerization domain (NOD2) gene. It is characterized by periodic fevers, gastrointestinal (GI) symptoms, arthritis, and dermatitis, among other symptoms. A sparse literature exists on this disease, and little is known about its dermatological manifestations. A review of available literature was performed to characterize the cutaneous manifestations of Yao syndrome. Cutaneous manifestations were documented in 85.7% of patients, with common characteristic descriptions of erythematous patches and plaques involving the face, trunk, abdomen, and extremities. Based on our review of treatment modalities employed for Yao syndrome, prednisone is an appropriate initial approach, with oral sulfasalazine and other disease‐modifying antirheumatic drugs serving as appropriate secondary options. YAOS should be considered in the differential diagnosis of patients presenting with a dermatitic rash, especially in the context of concurrent articular symptoms, periodic fever, and GI symptoms.