Acquired Port-wine Stain With Superimposed Eczema Following Penetrating Abdominal Trauma

Comment

The exact cause of PWS is unknown. There have been a multitude of genomic suspects for congenital lesions, including a somatic activating mutation (ie, a mutation acquired during fetal development) of the GNAQ (guanine nucleotide binding protein [G protein], q polypeptide) gene, which may contribute to abnormal cell proliferation including the regulation of blood vessels, and inactivating mutations in the RASA1 (RAS p21 protein activator [GTPase activating protein] 1) gene, which controls endothelial cell organization.^19-22 Later mutations (ie, those occurring after the first trimester) may be more likely to result in isolated PWSs as opposed to syndromic PWSs.¹⁹ Whatever the source of genetic misinformation, it is thought that the diminished neuronal control of blood flow and the resulting alterations in dermal structure contribute to the pathogenesis of PWS and its associated histologic features.^7,23

The clinical and histopathologic features of acquired PWSs are indistinguishable from those of congenital lesions, indicating that different processes may lead to the same presentation.⁴ Abnormal innervation and decreased supportive stroma have both been identified as contributing factors in the development of congenital and acquired PWSs.^7,23-25 Rosen and Smoller²³ found that diminished nerve density affects vascular tone and caliber in PWSs and had hypothesized in a prior report that decreased perivascular Schwann cells may indicate abnormal sympathetic innervation.⁷ Since then, PWS has been shown to lack both somatic and sensory innervation.²⁴ Tsuji and Sawabe²⁵ indicated that alterations to the perivascular stroma, whether congenital or as a result of trauma, decrease support for vessels, leading to ectasia.

In addition to an acquired PWS, our patient also had associated eczema within the PWS. Eczematous lesions were absent elsewhere, and he did not have a history of childhood eczema. Our review of the literature yielded 8 studies since 1996 that collectively described 30 cases of eczema within PWSs.^11-18 Only 2 of these reports described adult patients with concomitant eczema and PWS and none described acquired PWS.^13,18

Few studies have addressed the relationship between PWSs and eczema. It is unclear if concomitant PWS and localized eczema are collision dermatoses or if a PWS may predispose the affected skin to eczema.^11-13 It has been hypothesized that the increased dermal vasculature in PWSs predisposes the skin to the development of eczema—more specifically, that ectasia may lead to increased inflammation.^12,17 The concept of the “immunocompromised district” proposed by Ruocco et al²⁶ is a unifying theory that may underlie the association noted between cases of trauma and later development of a PWS and superimposed eczematous dermatitis, such as in our case. Trauma is noted as one of a number of possible disruptive forces affecting both immunomodulation and neuromodulation within a local area of skin, leading to increased susceptibility of that district to various cutaneous diseases.²⁶

Although our patient’s eczema responded to conservative treatment with a topical steroid, several case series have reported success with laser therapy in the treatment of PWS while preventing recurrence of associated eczematous dermatitis.^12,17 Following the cessation of eczema treatment with topical steroid, which causes vasoconstriction, we suggest postponing laser therapy several weeks to allow resolution of vasoconstriction, thus providing enhanced therapeutic targeting with a vascular laser. Of particular relevance to our case, a recent study showed efficacy of the pulsed dye laser in treating PWSs in Fitzpatrick skin types IV and V.²⁷

Conclusion

Although acquired PWS is rare, it can present later in life as an acquired lesion at a site of previous trauma.^1-5 Congenital capillary malformations also can be associated with superimposed, localized eczema.^11-18 We present a rarely reported case of an acquired PWS with superimposed, localized eczema. As in cases of congenital PWS with concomitant eczema, the associated eczema in our case was responsive to topical corticosteroid therapy. Additionally, pulsed dye laser has been shown to treat PWSs while preventing the recurrence of eczema, and it has been deemed effective for individuals with darker skin types.^{12,17, 27} Further studies are needed to explore the relationship between PWS and eczema.