Wetter, David A.

Overall, our findings expand current understanding of SDRIFE by highlighting both well-recognized and underappreciated medication classes, underscoring the importance of ongoing pharmacovigilance.

Vitamin D deficiency is frequently reported in hidradenitis suppurativa (HS), but its clinical significance remains unclear. In a retrospective cohort of 503 patients, deficiency was common and associated with demographic and metabolic factors but not with treatment-defined severity. Vitamin D deficiency was independently associated with elevated C-reactive protein, suggesting a link with systemic inflammation.

Abstract Cutaneous IgM/IgG immune complex vasculitis is a newly recognized provisional subtype of single-organ vasculitis that is clinically indistinguishable from IgA vasculitis. This retrospective case series evaluated the presence, clinicopathological characteristics and outcomes of patients with IgM and/or IgG dominance or codominance on direct immunofluorescence testing (2010–23). This review represents only the second study to date to characterize this population. Early analysis of 14 patients revealed that cutaneous IgM/IgG immune complex vasculitis was mainly skin limited, and treatment with topical and oral corticosteroids typically resulted in complete resolution without recurrence. Additionally, this study demonstrated that nearly two-thirds (64%) of patients with cutaneous small-vessel vasculitis with IgM and/or IgG dominance or codominance on direct immunofluorescence were ultimately found to have an underlying autoimmune connective tissue disease, cryoglobulinaemia, antineutrophil cytoplasmic antibody-associated vasculitis, infection or a drug-related cause. Therefore, it is imperative that clinicians perform a thorough investigation of this unique population to evaluate for potential underlying diseases and/or triggers.

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.