Diagnostic Workup
The diagnosis of SVV is based on compatible clinical, histological and laboratory findings. It is recommended to perform an initial screen to exclude infection, as infection can commonly mimic vasculitis. This includes obtaining blood cultures, echocardiogram, hepatitis screen (B and C), HIV test, anti-glomerular basement membrane antibody, antiphospholipid antibodies and antinuclear antibodies. To assess for the extent of vasculitis involvement, examine for internal organ involvement, even in individuals with isolated cutaneous vasculitis. This can be performed with a thorough history, physical examination, urine dipstick, chest radiograph, and nerve conduction studies. To confirm diagnosis, a biopsy is done, with the biopsy site choice dependent on its likelihood of affecting treatment decisions. To identify the specific type of small-vessel vasculitis, it is particularly important to check serum levels of ANCA, cryoglobulin, complement, and eosinophils/IgE. In addition, specific findings on biopsies such as the presence or absence of necrotizing granulomatous inflammation, IgA deposits, and immune complex formation can aid in specific diagnostic identification.[16] Figure 1 provides a summarized workup in diagnosing small-vessel vasculitis.
Figure 1.
Workup of a small-vessel vasculitis
Skin Therapy Letter. 2020;25(3):5-8. © 2020 SkinCareGuide.com
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