Reactivation of Herpes Simplex Virus and Cytomegalovirus in a Case of Thymoma-associated Graft-versus-host Disease-like Erythroderma

Abstract

a 64-year-old woman with a 4-year history of pruritic erythema was admitted to our hospital because of aggravation of the erythema that did not respond to 20 mg/ day oral prednisolone. The patient had had malignant thymoma and myasthenia gravis for 12 years, together with recurrent oral herpes infection for several years. In spite of thymectomy, chemotherapy, and radiation therapy, malignant thymoma was disseminated to the thoracic cavity and no more treatment options could be utilized on admission. The patient presented with erythema that was scaly, mildly keratotic, and distributed over the face, body trunk, and extremities (Fig. 1a). The patient reported severe pruritus. Biopsy specimen of the erythema revealed superficial perivascular dermatitis with parakeratosis, hypogranulosis, dyskeratosis with satellite cell necrosis, mild acanthosis, and vacuolar change in the epidermis, and moderate infiltration of lymphocytes in the upper dermis (Fig. 1b). Direct immunofluorescence was negative (data not shown). Immunohistochemistry revealed that there were more CD8+ T cells than CD4+ T cells infiltrated in the epidermis and dermis (Fig. 1c, d). Differential diagnoses included psoriasis, lichen planus, pityriasis rosea, lichenoid drug eruption, pityriasis lichenoides chronica, and thymoma-associated GVHD-like erythroderma. psoriasis was ruled out by the presence of dyskeratosis, and parakeratosis is not usually observed in lichen planus. The clinical course was too long for pityriasis rosea, and lichenoid drug eruption could be ruled out because of the absence of eosinophils in the dermis. Furthermore, pityriasis lichenoides chronica is not usually pruritic and the eruptions are more oval than those of our case. Based on the characteristic distribution and clinical features of the erythema and pathological findings, a diagnosis of thymoma-associated GVHD-like erythroderma was made. potent topical steroid (clobetasol propionate 0.05%), systemic steroid (prednisolone 2 mg/kg/day), and cyclosporine (5 mg/kg/day) were prescribed for 2 weeks, but did not control the erythema (Fig. s1; available from http://www.medicaljournals.se/acta/content/?d oi=10.2340/00015555-1577). Intriguingly, after the initiation of oral acyclovir (15 mg/kg/day) for exacerbated oral herpes infection, the erythema began to subside. acyclovir was then switched to valacyclovir hydrochloride (15 mg/kg/day). Incidentally, we detected a high level of CMV antigenemia of up to 1,564 cells/slide, although it was only 11 cells/slide 6 months previously. The patient did not report any symptoms of retinitis, pneumonia, or colitis, thus we administered ganciclovir (5 mg/kg/day) and discontinued valacyclovir. The erythema recurred when prednisolone was tapered to 0.75 mg/kg/day; therefore, prednisolone was increased up to 1 mg/kg/day, which was not successful. Next, broadband ultraviolet Reactivation of Herpes Simplex Virus and Cytomegalovirus in a Case of Thymoma-associated Graft-versus-host Disease-like Erythroderma