Clinically active extrinsic atopic dermatitis (AD) is associated with an increased risk for eczema herpeticum (EH), a herpes simplex viral infection of inflamed skin, study data published in the Journal of the European Academy of Dermatology and Venereology suggest.
Investigators performed a retrospective analysis that included patients with EH (n=224) who were seen during a 10-year period by dermatologists at 8 European university hospitals. Patients with AD were divided into subsets of extrinsic and intrinsic AD. Patients who presented with elevated total serum immunoglobulin E (IgE) levels of ≥100 kU/L, positive results in standard skin prick tests, positive SX-1- or FX-5-CAP-FEIA, a history of allergic rhinoconjunctivitis, and/or a history of allergic bronchial asthma were considered to have extrinsic AD. Researchers also examined patients’ history and serum levels of anti-HSV-IgM and anti-HSV-IgG antibodies to identify primary or secondary herpes simplex virus infections.
On average, it took 4.2±3.4 days to diagnose EH after patients realized their first symptoms. A total of 133 patients experienced their first EH episode, whereas 17 patients had the infection twice, and another 17 patients were affected by >2 episodes. Extrinsic AD was found to be a risk factor for EH, represented by 184 cases of EH in patients with extrinsic AD compared with only 1 patient who had intrinsic AD (P <.001). Recurrent EH was associated with a younger age at AD onset compared with patients with a single episode of EH (5.4±12.9 years vs 11.1±6.5 years, respectively; P =.016).
A limitation of the study was its retrospective design, which resulted in missing long-term follow-up data for some of the patients.
Researchers from this study hope their findings “can help to differentiate EH from other skin conditions and will hopefully lead to a faster diagnosis of affected patients.”
Seegräber M, Worm M, Werfel T, et al. Recurrent eczema herpeticum – a retrospective European multicenter study evaluating the clinical characteristics of eczema herpeticum cases in atopic dermatitis patients [published online November 16, 2019]. J Eur Acad Dermatol Venereol. doi:10.1111/jdv.16090