Brachiola vesicularum, N. G., N. Sp., a New Microsporidium Associated with AIDS and Myositis

Abstract

Brachiola vesicularum, n. g., n. sp., is a new microsporidum associated with AIDS and myositis. Biopsied muscle tissue, examined by light and electron microscopy, revealed the presence of organisms developing in direct contact with muscle cell cytoplasm and fibers. No other tissue types were infected. All parasite stages contain diplokaryotic nuclei and all cell division is by binary fission. Sporogony is disporoblastic, producing 2.9 x 2 microns diplokaryotic spores containing 8-10 coils of the polar filament arranged in one to three rows, usually two. Additionally, this microsporidium produces electron-dense extracellular secretions and vesiculotubular appendages similar to Nosema algerae. However, the production of protoplasmic extensions which may branch and terminate in extensive vesiculotubular structures is unique to this parasite. Additionally, unlike Nosema algerae, its development occurred at warm blooded host temperature (37-38 degrees C) and unlike Nosema connori, which disseminates to all tissue types, B. vesicularum infected only muscle cells. Thus, a new genus and species is proposed. Because of the similarities with the genus Nosema, this new genus is placed in the family Nosematidae. Successful clearing of this infection (both clinically and histologically) resulted from treatment with albendazole and itraconozole.

Ultrastructural examination of two cases of stromal microsporidial keratitis

“…Some form of immunosuppression [either by primary (hereditary) HIV infection, or by use of topical corticosteroids or other forms of systemic immunosuppression] is certainly one factor. The other may be a slightly lower temperature (Cali et al, 1998). If some of the microsporidian parasites found in humans are from poikilothermic (cold-blooded) animals, then the slightly lower temperature of the eye (because of its exposed position) may allow opportunistic parasite development to become established, causing symptoms, whereas, development in deeper (and warmer) tissues could curtail parasite development (Trammer et al, 1997).…”

Fatal Myositis Due to the MicrosporidianBrachiola algerae,a Mosquito Pathogen

“…The diagnosis of a microsporidian infection was established by the demonstration of characteristic spores and proliferative stages consistent with B. algerae. 5,7 Both B. algerae and B. vesicularum produce extensive vesicular appendages that extend into the host-cell cytoplasm, but only B. vesicularum produces branching protoplasmic extensions. 5,7 The diagnosis was confirmed by molecular phylogeny with the use of the small-subunit rRNA gene.…”

“…7 Thin sections were stained with uranyl acetate and lead citrate. The samples were examined with the use of a Tecnai 12 transmission electron microscope at the Rutgers University electron-microscopy facility.…”

Microsporidia and acquired immunodeficiency syndrome

“…The species B. vesicularum was found in a patient with Aids associated with myositis (Cali et al 1998). In the mature spores of the diplokaryotic B. vesicularum, the polar tube forms two rows of coils, each row with 8 to 10 coils, but they can also be arranged in single and triple rows of coils.…”

“…The formerly described B. connori (Sprague 1974) is a synonym for N. connoris (Sprague 1974, Cali et al 1998.…”