ISOLATION AND IDENTIFICATION OF ENCEPHALITOZOON HELLEM FROM AN ITALIAN AIDS PATIENT WITH DISSEMINATED MICROSPORIDIOSIS

Microsporidia are primitive mitochondria-lacking spore-forming eukaryo tic protozoa that infect a wide variety of animals and also humans. Of the five genera (Encephalitozoon, Enterocytozoon, Septata, Nosema and Pleistophora) that cause infections in humans, Enterocytozoon bieneus i, Septata intestinalis, and Encephalitozoon hellem are being increasi ngly identified in patients with acquired immunodeficiency syndrome (A IDS). E. bieneusi causes gastrointestinal disease, S. intestinalis cau ses gastrointestinal and disseminated disease, and E. hellem causes oc ular as well as disseminated disease. We have established in continuou s culture a strain of microsporidia isolated from the urine and throat washings of an Italian AIDS patient and identified it as Encephalitoz oon hellem, based on its ultrastructural morphology, antigenic pattern , and polymerase chain reaction-amplified small subunit ribosomal RNA. We believe that this is the first time that a strain of microsporidia has been isolated from the throat washings of a patient with microspo ridiosis.