Cerebral Microsporidiosis Due toEncephalitozoon cuniculiin a Patient with Human Immunodeficiency Virus Infection

Abstract

Microsporidia are obligate, intracellular, spore-forming protozoa that are parasitic in every major animal group.¹ Cerebral microsporidial infection was first described in 1922 in rabbits with granulomatous encephalitis,² and the organism was named Encephalitozoon cuniculi. ³ In 1959 and 1984, two cases of infection in children with seizure disorders were attributed to E. cuniculi. ^4,5 The diagnosis was based on light-microscopical detection of microsporidial spores in cerebrospinal fluid and urine samples, but the identification of the species remained inconclusive, because immunologic and molecular techniques to distinguish among encephalitozoon-like microsporidia were not available at that time. In recent years, three distinct encephalitozoon species (E. hellem, E. intestinalis, and E. cuniculi) with most of the morphologic features of E. cuniculi of animal origin have been detected in persons with human immunodeficiency virus (HIV) infection who had hepatitis, peritonitis, keratoconjunctivitis, nephritis, cystitis, bronchiolitis, sinusitis, or diarrhea.⁶