Hydroa Vacciniforme Workup

Updated: Aug 05, 2019
  • Author: Gregory Toy; Chief Editor: Dirk M Elston, MD  more...
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Laboratory Studies

See the list below:

  • Complete blood cell count to investigate constitutional symptoms

  • Viral culture of blister fluid to rule out herpes virus infection

  • Erythrocyte sedimentation rate and antinuclear antibody, anti-Ro, and anti-La antibody tests to rule out bullous lupus erythematosus

  • Plasma or serum porphyrin assay to exclude cutaneous porphyrias

  • DNA repair studies to rule out xeroderma pigmentosum

  • Measurement of EBV DNA; best detected with whole blood rather than serum or plasma


Imaging Studies

Imaging studies are not routinely obtained as part of the workup of hydroa vacciniforme (HV).


Other Tests

Repetitive, broad-spectrum, UV-A phototesting may be warranted. Repetitive, broad-spectrum, low-dose UV-A irradiation can elicit lesions clinically and histologically identical to those produced by natural UV exposure, although results are inconsistent. The minimal erythemal dose of UV-B and UV-A in these patients is reduced. [28]


Histologic Findings

Early lesions reveal an epidermal, multilocular vesicle with reticular degeneration and demonstrate EBV RNA (EBER positive) in lymphocytes. [29]  A dense, perivascular, lymphohistiocytic infiltrate with vessel hemorrhage may occur in the dermis. Late lesions show epidermal and dermal necrosis with a surrounding, chronic, inflammatory infiltrate. Direct immunofluorescence study results are usually normal, except for rare reports (2 patients) of C3 deposits at the dermoepidermal junction and in the small dermal vessels.