Wiskott–Aldrich syndrome and molluscum contagiosum: a therapeutic challenge after reaction to cidofovir

Abstract

A 43-year-old white man with molluscum contagiosum and a history of Wiskott–Aldrich syndrome presented to our clinic. He had previously finished six cycles of chemotherapy with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone), and had achieved complete remission for diffuse large B-cell lymphoma. The patient had a 1.5-year history of molluscum contagiosum that had spread to the entire trunk and upper and lower extremities. Past therapies included liquid nitrogen cryotherapy, imiquimod, cantharidin, curettage, topical emollients (Dermasil), salicylic acid (Clear Away and Compound W), and trichloroacetic acid peel. Most recently, topical cidofovir had resulted in severe edema of the left arm. On physical examination, the patient had hundreds of umbilicated, flesh-colored to erythematous papules over his body(1, 2). A lesional biopsy of a 5-mm umbilicated papule from the left axilla showed epidermal cells and infundibular hair follicles with large intracytoplasmic molluscum inclusion bodies. Figure 1Open in figure viewerPowerPoint Disseminated molluscum-lower back Figure 2Open in figure viewerPowerPoint Disseminated molluscum-upper chest Laboratory results included a normal metabolic panel, complete blood count (CBC), and liver function tests (LFTs), as well as a negative human immunodeficiency virus (HIV) test. The patient's immunoglobulin E (IgE), IgG, and IgA were all normal. However, abnormally low laboratory values included an IgM of 17 mg/dL and absolute CD4 and CD8 counts of 203 and 41 µL, respectively. Initial therapy included topical imiquimod and oral acitretin 25 mg daily. Three months later, the patient showed slight improvement only and acitretin was discontinued. He had also been using salicylic acid (Compound W) and silver nitrate applications. Most recently, the plan included continuation of cantharidin toothpick treatment and imiquimod, and the potential addition of systemic interferons (γ or α) and topical or intravenous cidofovir.