Disseminated acanthamebiasis in patients with AIDS. A report of five cases and a review of the literature

Abstract

Background: Acanthamoeba and Leptomyxida are free-living amebae that cause granulomatous amebic encephalitis, a rare, slowly progressive, fatal neurologic process seen in immunosuppressed hosts. In addition, these organisms produce disseminated cutaneous lesions and involve other organs, particularly in patients with the acquired immunodeficiency syndrome (AIDS).

Results: We report five cases of disseminated acanthamebiasis in patients with AIDS, each with cutaneous manifestations but lacking central nervous system involvement. The medial CD4+ T-cell count was 0.024 x 10(9)/L. Skin lesions included pustules, subcutaneous and deep dermal nodules, and ulcers, most often seen on the extremities and face. Histopathologically, both pustular and vasculitic changes were observed; in all cases, the microscopic identification of organisms was difficult because of the macrophagelike appearance of the microbes in routine sections.

Conclusions: Skin lesions are the most common reported presentation of infections caused by Acanthamoeba and Leptomyxida organisms in patients with AIDS, a minority of whom have central nervous system manifestations. A high index of suspicion is necessary for both the dermatologist and the dermatopathologist. Prognosis is guarded, but early treatment using a combination of intravenous pentamidine and oral fluconazole, sulfadiazine, and flucytosine may be beneficial.